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TextReader.Peek Method

Microsoft Silverlight will reach end of support after October 2021. Learn more.

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 input stream.

Namespace:  System.IO
Assembly:  mscorlib (in mscorlib.dll)

Syntax

'Declaration
Public Overridable Function Peek As Integer
public virtual int Peek()

Return Value

Type: System.Int32
An integer representing the next character to be read, or -1 if no more characters are available or the stream does not support seeking.

Exceptions

Exception Condition
ObjectDisposedException

The TextReader is closed.

IOException

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.

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.