File.ReadLines Method (String)

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

When it is called by trusted applications, reads the lines of a file.

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

Syntax

'Declaration
Public Shared Function ReadLines ( _
    path As String _
) As IEnumerable(Of String)

public static IEnumerable<string> ReadLines(
    string path
)

Exception	Condition
ArgumentException	path is a zero-length string, contains only white space, or contains one or more invalid characters defined by the GetInvalidPathChars method.
ArgumentNullException	path 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.
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.

You can use the ReadLines method to do the following:

Perform queries on a file to obtain a filtered set of its lines.
Write the returned collection of lines to a file with the File.WriteAllLines(String, IEnumerable<String>) method, or append them to an existing file with the File.AppendAllLines(String, IEnumerable<String>) method.
Create an immediately populated instance of a collection that takes an IEnumerable<T> collection of strings for its constructor, such as a IList<T> or a Queue<T>.

Supported in: 5, 4

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