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Hello and welcome.

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In this lecture we are going to convert to string.

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We are also going to truncate a value so I'm going to introduce another data type called double.

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We're going to try and convert that into an integer and integers and whole number and in the process

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of converting it it will be truncated.

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Okay.

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I've got visual studio open.

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And this is where we left off in our previous lectures.

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So I'm going to I'm going to comment out this code by doing two slashes and comment out on that as well.

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So what I'm gonna do I'm going to create new variables one to create a variable and the data type will

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be double.

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I'll give it a value of k I'll set the value to three point five semicolon at the end.

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Next hour reintroduce variable I and set this value to

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I'm going to pass it an integer value or set a value to be an integer of k.

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So basically what it will do it will convert this K here value into an integer an integer is a whole

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number and in the process of doing that it will truncate truncate means because a integer does not cannot

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read decimals.

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So it will just leave the point five out and only display the three.

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So that's what truncating means.

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So next we go to to introduce our result label.

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Remember we created the result label dot text so it takes in a text value.

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So we're going to eventually make this convert this value as well.

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Now set this to equal to the variable I as you can see as a red squiggly thing on the net because it's

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complaining that that local variable is an integer we cannot implicitly implicitly convert the type

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int to his drink.

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Right.

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We can using a helper method called two strings.

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So we're going to use a helper method to do the conversion so we can make it recognize a an integer

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and the way we do this where we've got I we just get rid of the semicolon and adopt.

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That would give us some intelligence points so this with what we want.

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We want to convert it to string due to string and place the semicolon.

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All right.

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So if I save that and execute this code it should output three.

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It would truncate the point five.

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All right.

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So that's what this is.

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So let me run that click on run

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so if I click Okay issued output three you can see is output at three but left out the point five.

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So so far we've been able to convert to string using the two string method is called a helper method.

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Okay so we're going to expand on the application further using the controls we created.

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So we are going to make it possible for a user to type in a number.

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Remember we created a text ball but we're going to configured it in such a way that a user can type

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in a number and we can perform calculation based on that number and then display the result.

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Okay.

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All right.

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So we will need to perform at least two types of conversion.

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So again the text box control stores user inputs into a string.

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So we want to convert that string into an integer in order to perform a calculation on it.

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The label controls stores result as a string.

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We will want to convert that result of the integer calculation back into a string.

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OK.

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So I'm going to comment out this line of code here and introduce some other code that we can use with

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our design controls.

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OK.

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So what I wanted we want to make this controls active.

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So.

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All right.

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So I'm going to introduce some more different variables here now to save time.

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I've already written the code here.

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So I've got some code here from line 27 to 30.

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So I've created another date a string type.

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And given it the variable value of i and I've set it to equal to the input text box dot text I've created

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a lot of variable called J which is an integer data type and I've set the value to equal to to int dot

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pass and past the value of i.

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Which is this textbook here.

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What we're doing here we're converting this string to an integer via the int dot pass.

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How permitted.

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OK so the int dot pass helper method is a bit different from the two string l permitted.

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Right we've used that earlier on this shows that the main difference is that the pass helper method

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comes from inside of the int class and takes in a string as an input in between the method parentheses.

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All right.

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So this I here is referring to this input text value.

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So with this piece of code here now the user input will be stored as an integer.

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All right.

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In the int j which is this one that will be stored as an integer and we can now perform calculations.

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All right.

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And display the result.

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True the label control which is this one here.

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All right.

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So we simply what we're doing here we're converting the K to a string.

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So let's save that and run the code.

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Okay.

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Okay.

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So this is the interface.

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If I'm typing because we've done the conversion to not be possible to type in values I type in 7 and

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click Okay.

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It should give me eight because of the code.

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There you go giving me eight typing in another value typing C6 you should give me seven.

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All right.

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The reason is adding an extra number is because of this code here.

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Line twenty nine so I've sent integer k so any value up.

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If I typed in as a K will give me the value of j plus 1.

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All right.

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So this J the integer here the pass method is doing the conversion.

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All right.

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So any thing are typing here as a J.

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It will add one to it.

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That's where we get in the the extra number from.

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So if I add for there and click okay it will give me five.

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What should happen if I type in a word for type in a word.

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Rick I should get an arrow and click Okay.

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Notice the vicious to do immediately give me an error is telling me what's going on there.

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You can see visual studio as highlighted where the problem is why it failed to at runtime is giving

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me the exception error.

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All right.

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So the problem is that the int dot pass method will only work when the string looks exactly like in

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no runtime errors are quite difficult to be caught by the compiler.

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We've seen the compiler errors before where you see read quickly bits before you actually compile your

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code.

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The runtime errors are much more difficult to catch and one of the ways to catch them is basically true

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rigorous testing and one of the things you could put in place is to perform some checks on basic checks

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to check some validation checks if a user provides set enabled input it will check the format make sure

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the input is correct or not.

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So this kind of validation will help you know address the runtime errors.

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So I'll just stop the code from running by clicking that.

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So I sit in this lecture we successfully converted integer to string.

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We also perform a truncation.

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So now set for this lecture.

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Thank you so much for watching.

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Bye for now.