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Hello.

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In this video, we're going to talk about Question 15, what is the difference between type of and the

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type?

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Both type of keyword and the type of method are used to get the information about some type.

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The differences between them are that the type of takes, the name of the type we want to inspect.

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So we must know the type before type of is resolved at compile time.

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Good type is a method that must be executed on an object.

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Because of that, it is resolved at one time.

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This method comes from the system object based class, so it is available in any object in C-sharp both

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type of and get type method return an object of the type class this object hosts or information about

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the type.

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For example, it contains the type name list of the constructors.

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The base type implemented interfaces, et cetera.

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All right.

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Let's see type of and grid type in practice.

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If I know of the type already and they only wanted to get the type object for some reason, I can use

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the type of keyword.

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Here are used the type of was the base type, but here I executed the good type method on an object.

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In both cases, the result is the type object containing full information about the type called base.

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We don't always know the type at computation time, so we can't always use the type of keyword.

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Let's consider this method.

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This object can be anything, and it will only be known at random.

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What it is?

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Exactly.

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That's why I can't use type of here because I wouldn't know what to pass as the parameter.

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I must use the gift type formatted.

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Let's see the print type named method in action.

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As you can see, it's printer, the actual type of those objects.

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The important thing to understand is that grid type always returns the actual type of an object.

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Let's see an example.

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Even if this variable is of type base, I assigned an object of type direct to it, it is possible because

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derived inherits from base, the good type method printer, the actual type, we actually have seen

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this before in the print type method, even if it took a parameter of system, object type, it printer,

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the actual type of the given object.

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Remember, does the get type method belongs to the system object type so it can be called on an object

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in C-sharp?

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Let's summarize both type of and forget that method return a type object which holds the information

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about the type type of things, the name of a type, and it gets resolved at compilation time.

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The type method is called upon an object, so it is resolved at random.

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Both type of and the good type method are parts of the reflection mechanism, which we learn about in

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the next lecture.

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If this topic is touched during the interview, you can be asked What is the purpose of the gut type

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method?

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This method requires the type object which holds or information about the type of an object it was called

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on.

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The type object contains Phoenix like type name, list of constructors attributes, the best type,

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etc. One is the goods type method defined.

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It is defined in the system object type, which is a base type for all types in C sharp.

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This is why we can call the get type method on objects of a type.

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All right, thanks for watching, and I'll see you in the next lecture where we will discuss reflection.