File.AppendAllLines Method (String, IEnumerable<String>, Encoding)

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

When it is called by trusted applications, appends lines to a file by using a specified encoding, and then closes the file.

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

Syntax

'Declaration
Public Shared Sub AppendAllLines ( _
    path As String, _
    contents As IEnumerable(Of String), _
    encoding As Encoding _
)

public static void AppendAllLines(
    string path,
    IEnumerable<string> contents,
    Encoding encoding
)

contents
Type: System.Collections.Generic.IEnumerable<String>
The lines to append to the file.

Exception	Condition
ArgumentException	path is a zero-length string, contains only white space, or contains one more invalid characters defined by the GetInvalidPathChars method.
ArgumentNullException	Either path, contents, or encoding is nulla null reference (Nothing in Visual Basic).
DirectoryNotFoundException	path is invalid (for example, it is on an unmapped drive).
FileNotFoundException	The file specified by path was not found.
IOException	An I/O error occurred while opening the file.
PathTooLongException	path exceeds 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.
NotSupportedException	path is in an invalid format.
SecurityException	The caller does not have the required permission.
UnauthorizedAccessException	path specifies a file that is read-only. -or- This operation is not supported on the current platform. -or- path is a directory. -or- The caller does not have the required permission.

For more information about trusted applications, see Trusted Applications.

If the target file does not exist, it is created.

You can use this method to create a file that contains the following:

The results of a query on the lines of a file, as obtained by using the ReadLines method.
The contents of a collection that implements an IEnumerable<T> of strings.

Supported in: 5, 4

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