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File.AppendText Method

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

When it is called by trusted applications, creates a StreamWriter that appends UTF-8 encoded text to an existing file.

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

Syntax

'Declaration
Public Shared Function AppendText ( _
    path As String _
) As StreamWriter
public static StreamWriter AppendText(
    string path
)

Parameters

Return Value

Type: System.IO.StreamWriter
A StreamWriter that appends UTF-8 encoded text to an existing file.

Exceptions

Exception Condition
UnauthorizedAccessException

The caller does not have the required permission.

ArgumentException

path is a zero-length string, contains only white space, or contains one or more invalid characters as defined by GetInvalidPathChars.

ArgumentNullException

path is nulla null reference (Nothing in Visual Basic).

PathTooLongException

The specified path, file name, or both exceed the system-defined maximum length. For example, on Windows-based platforms, paths must be less than 248 characters, and file names must be less than 260 characters.

DirectoryNotFoundException

The specified path is invalid (for example, it is on an unmapped drive).

NotSupportedException

path is in an invalid format.

Remarks

For more information about trusted applications, see Trusted Applications.

Platform Notes

Silverlight for Windows Phone Silverlight for Windows Phone

 This member has a SecurityCriticalAttribute attribute on Silverlight for Windows Phone, because the attribute was present in Silverlight 3. This attribute restricts this member to internal use. Application code that uses this member throws a MethodAccessException.

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.

See Also

Reference