- You have seen in some of the examples that you can create a variable inside a method.. - subsequent statements in the same method can then use the variable. - To put it another way, the scope of a variable is simply the region of the program in which that variable is usable. - The scope of an identifier (of a variable or method) is linked to the location of the declaration that introduces the identifier into the program, as you'll now learn.. - Unlike local variables, you can use fields to share information between methods. - The variable myField is defined within the class, but outside of the methods firstMethod and anotherMethod. - In a method, you must declare a variable before you can use it. - A method can use a field before the statement that defines the field—the compiler sorts out the details for you!. - If two identifiers have the same name and are declared in the same scope, they are said to be overloaded. - For example, if you declare two local variables with the same name in the same method, you get a compile-time error. - Similarly, if you declare two fields with the same name in the same class or two identical methods in the same class, you also get a. - However, there is a way that you can overload an identifier, and that way is both useful and important.. - Consider the WriteLine method of the Console class. - However, when you type WriteLine in the Code and Text Editor window when writing C# code, you will notice that IntelliSense gives you 19 different options! Each version of the WriteLine method takes a different set of. - At compile time, the compiler looks at the types of the arguments you are passing in and then calls the version of the method that has a matching set of parameters. - Overloading is primarily useful when you need to perform the same operation on. - You can overload a method when the different implementations have different sets of parameters. - that is, when they have the same name but a different. - number of parameters, or when the types of the parameters differ. - This capability is allowed so that, when you call a method, you can supply a comma-separated list of arguments, and the number and type of the arguments is used by the compiler to select one of the overloaded methods. - However, note that although you can overload the parameters of a method, you can't overload the return type of a method. - In other words, you can't declare two methods with the same name that differ only in their return type.
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