Windows apps
Collapse the table of content
Expand the table of content
Information
The topic you requested is included in another documentation set. For convenience, it's displayed below. Choose Switch to see the topic in its original location.

File.AppendAllText Method (String, String)

When it is called by trusted applications, appends the specified string to the file, and then closes the file. If the file does not exist, this method creates a file, writes the specified string to the file, then closes the file.

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

public static void AppendAllText(
	string path,
	string contents
)

Parameters

path
Type: System.String
The file to append the specified string to.
contents
Type: System.String
The string to append to the file.

ExceptionCondition
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 null.

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).

IOException

An I/O error occurred while opening the file.

UnauthorizedAccessException

path specified a file that is read-only.

-or-

This operation is not supported on the current platform.

-or-

path specified a directory.

-or-

The caller does not have the required permission.

FileNotFoundException

The file specified in path was not found.

NotSupportedException

path is in an invalid format.

SecurityException

The caller does not have the required permission.

Silverlight

Supported in: 5, 4

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

Community Additions

Show:
© 2016 Microsoft