WriteLineAsync Method (String)

StreamWriter.WriteLineAsync Method (String)

.NET Framework 4.6 and 4.5

Writes a string followed by a line terminator asynchronously to the stream.

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

[HostProtectionAttribute(SecurityAction.LinkDemand, ExternalThreading = true)]
public override Task WriteLineAsync(
	string value


Type: System.String

The string to write. If the value is null, only a line terminator is written.

Return Value

Type: System.Threading.Tasks.Task

A task that represents the asynchronous write operation.

Exception Condition

The stream writer is disposed.


The stream writer is currently in use by a previous write operation.

The line terminator is defined by the TextWriter.NewLine property.

The following example shows how to write two lines that consist of string values to a text file by using the WriteLineAsync(String) method.

using System;
using System.IO;

namespace ConsoleApplication
    class Program
        static void Main(string[] args)

        static async void WriteCharacters()
            using (StreamWriter writer = File.CreateText("newfile.txt"))
                await writer.WriteLineAsync("First line of example");
                await writer.WriteLineAsync("and second line");

Universal Windows Platform
Available since 4.5
.NET Framework
Available since 4.5
Portable Class Library
Supported in: portable .NET platforms
Windows Phone Silverlight
Available since 8.0
Windows Phone
Available since 8.1
Return to top
© 2015 Microsoft