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In this video we're going to start designing a screen to help us manage our vehicle listings so lets

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us just start our application and refresh ourselves with what we've done so far.

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And we have many listing here that allows us to add remove edit and view listings.

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So I'm actually just going to do all of that from.

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Well one window.

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And you know.

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Case by case you probably design something else.

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So I'm going to modify this entire listing or this entire menu strip and just have mileage vehicle listing

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someone to remove all of the child options of that menu and I can just click and delete.

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So when I click that one I did select that I could just press delete and it will actually just remove

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that menu item.

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So that's so you can go about removing them.

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Right.

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So I want one that says manage vehicle listing now when I click it I'm going to launch a new form that's

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a mean to see all the vehicles in the database and then perform the crowd activities from there.

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So I'm going to do everything from one window.

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So firstly I want to double click and do the Click event on that button.

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So there are a number of activities that need to be done.

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And I agree it takes and they don't need to be done in any particular order.

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So I'm creating the Click event but I'm not going to put anything in the click event because well the

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ultimate reason for that given would be to launch the window and I haven't yet created that farm right.

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So yes I have the tick given what I need to create the form.

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So in no particular order I have stuff to do I'm just saying that to say that you don't do one thing

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that the of a strict order of or series of activities that have to be performed in a particular order.

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Right so of the click event already we can come up to that but I'm went to regulate my project go to

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add say new item.

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And once again I'm creating a blank form and then this time I'm going to call it manage vehicle listing.

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All right.

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So my form is manage vehicle listing I can spend some time doing some cosmetic changes where I'm going

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to meet the text in the title bar not look.

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So you know programming will look like.

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All right.

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So manage vehicle listing and then I'm going to start looking at some new controls.

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And the first new control would be the grid view control.

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So in my tool box I'm going to go into the subcategory data and then I'd want to see one that is data

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grid view so data grid view displays rows and columns of data in a grid that you can customize.

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All right.

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So that is what we're going to drive over.

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So I drove over that data grid view and you notice that it's just this big green box.

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So I'm just going to expand this grid box to a certain extent.

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If I use that current I get by that menu and I can edit columns and columns you know enable it edit

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delete and add addition functions to the grid if I want I can also dock in the containers if I'm not

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going to Gunton and fills the entire container right.

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That's not necessarily what I want because I'm going to put the entire label at the top to say manage

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vehicle this.

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And I'm also going to put in some other things in here.

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So you know maybe it starts off with one idea of what you want to do and then you realize that oh but

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you don't have to do it that way you could do it another way.

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Sometimes that happens so let's start off by not having it docked and then going to bring over a label.

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So I have a label in add our entire record already.

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So instead of going and trying to design a brand new label I'm just going to copy this going back over

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to my new form paste it make sure I position it and I'm going to change the text I go to properties

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change it takes and this one is manage vehicle listing all right.

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So this reposition it accordingly.

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All right so our new window for managing the vehicle listing no most important the most important parts

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of this is our grid view saw a grid view will give us like a tabular representation of whatever data

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we tell it that we want to see.

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Right.

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So you can think of Excel or even in the database when we did a select star from a table that we saw.

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We notice that we get that tabular representation.

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That's exactly what that data grid view of those us to do.

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So the first thing that we do with these what I call them more essential controls because a label is

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essential but not that much.

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But I want to know the name of my grid view right.

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So I go to properties of the thinking grid view and you can take some time and look at the properties

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and realize that these properties whatever control their different properties and of course each control

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is unique in its own right.

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But the one the one common property is going to be name.

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And I don't want my data grid view to because it's a grid view someone to call this dv you know are

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GV grid view.

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Right.

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And this is car these star vehicles which are row on so remember my prefix and then the name of whatever

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it is that this control is for.

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So a grid view for vehicle lists.

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Then I'm going to set up this farm that when it loads I run a query for the vehicles and I put that

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data are the data that's going back from that query inside of this grid view.

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Right.

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So remember we did something similar to that when we were looking at launching our car or was it our

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ad or into the record form when we wanted to make sure that our combo box had all the data it needed

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from the listing of cars.

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Right.

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So in this case you want the grid view to have that same data when the form loads.

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So since I wanted to happen when the form loads the when this happens that is the events that I want.

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So I'm going to click on the form go over to properties the lightning bolt and I'm seeing that when

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the form loads I want this particular thing to happen.

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So I'm just going to double click inside the load section and know it's saying okay this is the farm

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name on the score load.

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So when the farm loads What do I want to happen.

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So the next thing I want to do of course is establish a database connection and then I can start earning

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my query.

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So if you forgot how that works you can go back to the order into the record code file where what we

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did was declare an object that represented our connection to the database we initialize it inside of

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for constructor and then wherever we needed to access the database we simply called on that object right.

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So we're going to follow that same pattern.

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So in our new form the first thing I want to do is in the class I'm defining our private and I'm making

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it read only that's muscle memory because it doesn't it that's always happens.

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So you know you can do it with all the read only.

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That's fine but I wanted to be off type car or into entities though if you forgot where this name came

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from.

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Then in the e d m x file that you would have created for this project.

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That's a car into a DB the idea makes in my case but if you have a different name it must be dot e DMX.

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You can double click that's use C or D It's a model but when you go to properties you will see entity

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country in your name and that is the class type that represents the connection to your database.

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All right so if you have forget the name or you are doing one from scratch you just looking at entity

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country in your name and whatever name is there that is your data type.

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All right.

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So back in our new code file for our new form we say a private read only date.

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Sorry.

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Car Into entities which is our entity contain a name and that I'm going to give it the object name so

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visual studio is always making suggestions and that's really cool.

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I took one of the additions in the previous form where I said add car and let me find that code quickly.

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So in the previous one where I access the database I use the resource through those suggestions.

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And that's fine but a lot of the times on the internet you probably see something like context being

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used or underscored D.B. The fact is the name of the object is not it's not it's inconsequential to

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the functionality.

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All right.

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So I can name my object anything.

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So in this situation I'm going to name it underscored DB.

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That being said over I do promote consistency so if you started on one path continued on that path.

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If you want to change the path change a path right through your code so don't have underscored D.B.

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in this form.

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And then car into a record or into entities in another form and then another form a field another way

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and you call its contact star X..

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Don't don't do that doesn't have one consistent naming convention.

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I'm doing it this way just to show you that whatever you call the object is inconsequential.

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All right.

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Someone to use D.B. in this situation however later on I will go through and normalize everything to

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underscore D.B..

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All right.

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So private read only car into entities the B and then inside of my constructor on an I underneath initialized

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component I'm going to see on the score d d equal to a new instance of car into entities.

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So that's the initialization right.

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So in our program runs are when this form is launched it knows all of the DV.

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Then initialize is its components and the DB.

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And then throughout the rest of the form any time we need to talk to our database we have or underscore

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D.B. object.

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So the first thing I want to do is run the query to get the car words to say var cars and I use cars

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and vehicles interchangeably so whichever one you want to use that's fine but var cars is equal to database

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connection Dot and I don't want the car into a record.

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So I kind of scroll until I see the table that looks like what I want which is types of cars.

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And then I can see a dot to list.

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So I want the list or at least of the types of cars in my database and then I'm storing all of those

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inside of a variable called cars.

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All right.

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And then the next step would be to let the data grid know that each should be displaying whatever is

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going back instead of the list of cars.

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So I can see GV.

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All right.

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So because I renamed it I know it's a grid view so I call it GV vehicle list dot data source is equal

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to cars.

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Right.

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So the list of cars going back from the database will serve as the data source for my data grid.

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So let us see how that looks.

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I click start and then when the window comes up I'm clicking and nothing is happening otherwise nothing

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happening and we see that we still have a street menu item but nothing is happening and that's because

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I did not finish up my click event so I finished wiring up the form or at least for now I've wired the

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form so I'm going to go back over to my main window design or to the code file or rather and then here

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is that click events I have to go to design because I missed a menu item so I need to delete this one.

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All right good.

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So now that we've cleaned up the interface back in our code file what we need to do is let the button

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launch the new form.

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So I'm just going to say var and this one is going to be vehicle listing is equal to new and I call

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it vehicle mileage vehicle listing.

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All right.

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And then I have to say that it's MDI appearance.

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Is this so vehicle listing that Amber's a parent is equal to this which is mean window.

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And then finally after all of that out of the way I want to show.

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All right so let's try.

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That's getting someone to launch our application.

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And then when I click Vintage Vehicle listing now we're seeing our listing and look at this no.

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So we're seeing the grid view and I mean it looks somewhat anemic or we see the big green box.

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We see the grid filling out it does much of the box as possible.

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We see that we're getting about the I.D. and the name and this seemingly random column from the database

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called car into records.

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But the fact is that we are seeing the car rental records in that grid views and all we can go back

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to this window and maybe clean it up a bit.

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Someone's a get out of this.

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Someone to modify the width of this grid view because I really don't need to needed to fill that much

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space with two columns.

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So I'm seeing Aidid name and cover car rental records.

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How do I explain what that seemingly random column is.

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But I want to add the button so I did take it's the ability to edit to add and remove the cars from

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the menu listing in the main window so what I'm going to do is put buttons inside of this window that

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will be responsible for helping us do those actions right.

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So I went to have four buttons or three buttons so I made one button that I'm just copying and pasting

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and I have a spare one.

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All right.

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And then for my buttons for the properties one I want to take to see what I wanted to do so but no one

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let's say we want to meet this add new car right.

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The button three.

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I want this and other spin properties so that I don't have to keep on going in and going Oh it's so

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button three.

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I want this one to be edited.

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Car and then this one would be delete car.

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And then another important step to having my buttons is that I don't want them to be beaten and button

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one button to button three I want them to have sensible names that I can reference them in the code

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behind.

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Right.

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So but no one wants renamed to be GM.

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That's my prefix for a button car.

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All right.

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Edit car is going to be Beatty and edit car.

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All right.

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And then the final one would be Beatty and the lead car.

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All right.

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So then I can go ahead and create click events for them from no if I want.

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So I'm going to double click the ad car and notice because I gave it a sensible name.

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The click event is very clear.

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Beatty and ad car on the score click.

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Correct.

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So I can just go ahead and create all those events accordingly.

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So just go back and double click each until I have those click events and then this is why I don't like

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pinning properties because in when writing code it's not useful.

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Right.

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So then I have three button click events with three buttons on my form.

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So that's just some cosmetic stuff.

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That's a start again and see what that looks like.

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All right.

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So now we see that a grid is a bit smaller and we have the data being displayed.

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Sure.

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But then to the right we see our buttons and well they're all dead buttons because they have click events

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but the click events aren't doing anything just yet.

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So no I want to clean up the grid a bit.

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I don't want the I.D. and name columns to be displaying in come on letters like that.

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So what I'm going to do is inside of my form load phone shun when I set the data source I noticed that

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when the data grid is generating the columns relative to the data it is being fed.

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So I'm feeding it the list of cars and the list of cars each object has I.T. it has name and some list

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of car rental records.

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Right.

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Which I'll soon explain exactly what that is.

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Well at least later on we'll see exactly what that is.

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So what I'm going to do for my data grid is I'm going to say GV vehicle list dot and then I want to

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specify that I want the first column which I know is going to be I.T. second C columns.

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And if you have ever worked with Aries our collection.

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So we are working with that list and that's our collection type of a work with an array you know that

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the square brackets represent.

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You can specify exactly which subscript of the Ari you want.

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Right.

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So if you haven't.

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That's fine.

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So let me explain.

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So the columns here.

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This is a grid view control and then I'm saying I want the columns.

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And if it's columns that means it's off collection there's more than one columns.

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I want the first column which I know as a programmer is going to be Ida anyway so I can see square brackets

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zero because in computers you start counting from zero not one.

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Right.

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So the first subscript of 3 0.

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So the first script is 0 and then I want the property of this which is the header text to be equal to

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the text I.D. in all caps right.

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So I'm seeing that after I get this stuff cars and then I get and then I said the data source at this

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point all of the columns would have been generated.

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I am seeing that the first column that was generated I want the heretics to be I.D. And then I want

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the second column so I'm just going to duplicate that line and Jesus a subscript from 0 to 1.

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And I want this one to be name in all caps.

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All right.

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So let's see.

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Hold that look.

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So if I click Start then I'm going to see that I'm getting Idi name and I'm still seeing Kyra into records.

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But at least the column headers are changing accordingly.

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So that's encouraging at least.

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All right.

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So the next thing I want to do is to eliminate the fact that I'm getting but that seemingly random car

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into records column.

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But before I do that let me just explain a bit to what that represents.

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So I opened up my day it's a model which is the idea makes file and I'm seeing this yard.

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If we look in the table types of car or types of cars we will see that we have the idea we have the

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name and then below we have this navigation property called car and title records.

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Right.

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So just humor me for a bit and let me take you on this journey if you will have our intel system and

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then you will have a car that is rented multiple times then that means that this car is associated with

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multiple records.

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Right.

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So if I wanted to know how many times my I believe of a car called Lada or Honda how many times my Honda

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was rented then I would have literally at least off the times this car was rented.

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Right.

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So that is exactly what this navigation property represents.

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It says that for any car that you're going to look at I can show you the list off or into our records

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that it is associated with because they are related.

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All right.

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And then in the same way the car into record knows the exact type of car that was rented in this record.

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So this is whole link and an entity framework actually global it's helping you to form good relationships

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between your tables and actually query data across multiple tables with much ease but without getting

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too much into you know complicating exactly how they're used right.

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No I don't need the reference to the car rental records just yet.

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So back in my code file I'm going to tweak this query a bit to select exactly what I want.

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So this is doing a select style.

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And we did a select star in our adder into our record once again for our combo box where I said that

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doing it this way is just like seeing select star in this case with OnStar.

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We literally just want I.D. and name because when we're doing it this way we're getting but the random

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seemingly random column of car into the records.

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Right.

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So I'm going to go back and I'm going to show you how we can treat this someone to come in this place

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and I'm going to say that this is the way you do select star from types of cars right.

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Just so we're clear.

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But then I'm going to rewrite this story and I'm going to walk you through exactly what we're doing.

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So I'm going to save our cars.

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Once again is equal to the connection to the database not the table that I want.

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Well then I'm not willing to say at least this time I'm going to say not silly.

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All right.

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And then when I do that I'm going to have to work a bit of I want to call it magic.

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But as I said I'm here to guide you through.

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So I want to select just the two columns that I want.

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I'm sure if you do if you're used this school then you would think that you'd say Oh I.

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Come on in.

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Well it's unfortunately not that simply in C sharp.

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We're going to have to do what we call a lot of lambda expression where we create an object.

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All right.

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So this is lambda.

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So this.

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That's just it's right.

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There's nothing more to explain.

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The only thing I can explain here is that this doesn't have to be a Q.

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This could be a W.

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00:22:33,440 --> 00:22:35,300
This could be a word.

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I mean you can use any expression you want but the Q or whatever expression you you use here is going

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to represent every object that is inside of the collection.

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Right.

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So this is just how you start a lambda expression.

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You have an expression what you want is a letter or a word or whatever and then you have equal and then

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the greater than saying or I just called it the arrow.

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Right.

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So you have the expression then the arrow and then this allows you to see what columns you want from

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the table.

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So I am saying select then I initialize alumni expression and then using the lambda expression I can

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see CU dot I.D..

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Right.

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But then I don't want just idea I want a new object.

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So what I'm want to see is new and then I'm open up.

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I open up my curly braces and then inside of this I'm going to specify that I want.

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And Heidi being equal to Q Dot I.D. then I can use my comma and say I want a new a new property called

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name and it should have the value Q Dot name.

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00:23:58,720 --> 00:23:58,980
All right.

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00:23:59,260 --> 00:24:02,690
So if you're you still askew and aliasing.

335
00:24:02,700 --> 00:24:09,600
All right we're in escrow you would've said something like SELECT this and you give it an alias so that

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00:24:09,670 --> 00:24:17,370
selected the column I would say select I.D. as another name on select to name as something else or whatever.

337
00:24:17,410 --> 00:24:22,070
This is how you go about doing aliasing inside of the link.

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00:24:22,090 --> 00:24:22,780
Right.

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00:24:22,780 --> 00:24:29,350
So once again let me just walk you through what we're doing or saying I want to connect to the database.

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Give me the table and then I want to select.

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00:24:33,790 --> 00:24:39,840
And then we do a lambda expression and then after the lambda expression we are selecting a new object.

342
00:24:39,850 --> 00:24:42,680
So we're literally just building an object on the fly.

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This this is just a new object that we're creating for our own purpose and what I want in my object

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is a property called I.D. which is going to get the value that's coming from the database with an I.D.

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come on another property called name and it is going to get the value coming from the database with

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the word name.

347
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And once again these are aliases.

348
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Right.

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00:25:05,260 --> 00:25:11,860
So I could have used anything here I didn't have to use idea name again I could have used car I.D..

350
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Right.

351
00:25:13,090 --> 00:25:16,130
And I could have used car name.

352
00:25:16,210 --> 00:25:17,530
It doesn't really matter.

353
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So it's up to me to know what I am naming these.

354
00:25:21,010 --> 00:25:22,900
Once again these are aliases.

355
00:25:22,900 --> 00:25:30,040
If you are used to school and then for as many properties as they're coming back on I want and I want

356
00:25:30,040 --> 00:25:37,540
to create an alias I could just say Como and do the same alias e was lambda expression dot whichever

357
00:25:37,540 --> 00:25:38,710
column I want.

358
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All right lambda variable or other.

359
00:25:42,090 --> 00:25:46,620
And then after doing all of that I notice all of that's happened instead of the curly braces.

360
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Then I would end with a semicolon but then I would probably want to do a list also.

361
00:25:52,480 --> 00:25:54,670
So I like lists so.

362
00:25:54,700 --> 00:26:00,920
And just me it makes it much easier to just when you do a link query just make everything I list afterwards.

363
00:26:00,940 --> 00:26:05,410
If you're selecting expecting a collection of results.

364
00:26:05,410 --> 00:26:05,700
Right.

365
00:26:06,070 --> 00:26:10,990
And then some people would actually break this into multiple lines so they would actually do something

366
00:26:10,990 --> 00:26:20,270
like the query here and then they a dot select in another line and then so then they would do that.

367
00:26:20,300 --> 00:26:23,550
Oh it's a bit more I won't do that one though.

368
00:26:23,650 --> 00:26:28,300
So that is how you would go about building open aliasing system.

369
00:26:28,300 --> 00:26:39,020
So this situation will be more like select and then I would say something like I.D. as car I.D..

370
00:26:39,250 --> 00:26:48,550
Kamal name as car name from types of cars.

371
00:26:48,590 --> 00:26:49,870
Right.

372
00:26:49,960 --> 00:26:56,040
So I'm gonna show you that link is variable for that and it does create some wonderful obstruction from

373
00:26:56,040 --> 00:27:00,000
the typical school while maintaining C sharp code.

374
00:27:00,000 --> 00:27:02,490
It does take practice it does day getting used to.

375
00:27:02,730 --> 00:27:09,150
So if you will have to kind of do it to be able to reap the benefits of what it allows you to do.

376
00:27:09,150 --> 00:27:09,480
Right.

377
00:27:09,960 --> 00:27:16,850
So if I do start again and then we look at our grid we see that we're getting bug eyed.

378
00:27:16,860 --> 00:27:22,950
You are getting by name and we're only getting about those two we're not getting that third column again

379
00:27:22,950 --> 00:27:30,240
and that's once again because I specified what I wanted to select on even though I changed the names

380
00:27:30,270 --> 00:27:37,920
I still told the grid view that the IDA ideas should be the column name for the first one I name the

381
00:27:37,920 --> 00:27:43,860
column name for the second one so I'm just going to put our breakpoint at the point where we're sitting

382
00:27:43,860 --> 00:27:48,990
the data source and I want to close the window and I'm going to load it again and then I'm going to

383
00:27:48,990 --> 00:27:55,170
look instead of my car's variable where you see it's coming back with five and if you look at the object

384
00:27:55,230 --> 00:27:57,810
listing you're seeing car idea and car names.

385
00:27:57,810 --> 00:28:06,150
So we created custom objects that we wanted to create at least and then that that list of custom objects

386
00:28:06,420 --> 00:28:14,040
is being used as a data source for our grid and then we set the column names and then our grid is displayed.

387
00:28:14,070 --> 00:28:18,800
So I'm removing the breakpoint clicking continue and that is the okay.

388
00:28:18,840 --> 00:28:25,470
So in the next video we'll start looking at how we wire up these buttons for adding to the database

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editing car record and removing a car record.