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File.ReadLines Method (String, Encoding)

Read the lines of a file that has a specified encoding.

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

static member ReadLines : 
        path:string * 
        encoding:Encoding -> IEnumerable<string> 

Parameters

path
Type: System.String

The file to read.

encoding
Type: System.Text.Encoding

The encoding that is applied to the contents of the file.

Return Value

Type: System.Collections.Generic.IEnumerable(String)
All the lines of the file, or the lines that are the result of a query.

ExceptionCondition
ArgumentException

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

ArgumentNullException

path is a 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.

Use this method to specify an encoding to use read the file.

The ReadLines and ReadAllLines methods differ as follows: When you use ReadLines, you can start enumerating the collection of strings before the whole collection is returned. When you use ReadAllLines, you must wait for the whole array of strings be returned before you can access the array. Therefore, when you are working with very large files, ReadLines can be more efficient.

You can use the ReadLines method to do the following:

.NET Framework

Supported in: 4.5, 4

.NET Framework Client Profile

Supported in: 4

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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