The Peek method returns an integer value in order to determine whether the end of the file, or another error has occurred. This allows a user to first check if the returned value is -1 before casting it to a Char type.
The current position of the TextReader is not changed by this operation. The returned value is -1 if no more characters are available. The default implementation returns -1.
The TextReader class is an abstract class. Therefore, you do not instantiate it in your code. For an example of using the Peek method, see the StreamReader.Peek method.