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TextReader.Peek Method

Definition

Reads the next character without changing the state of the reader or the character source. Returns the next available character without actually reading it from the reader.

public:
 virtual int Peek();
public virtual int Peek ();
abstract member Peek : unit -> int
override this.Peek : unit -> int
Public Overridable Function Peek () As Integer

Returns

An integer representing the next character to be read, or -1 if no more characters are available or the reader does not support seeking.

Exceptions

An I/O error occurs.

Remarks

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.

Applies to

See also