StringWriter.WriteLineAsync Method

Definition

Namespace:

System.IO

Assemblies:

netstandard.dll, System.Runtime.dll

Asynchronously writes data to the string, followed by a line terminator.

Overloads

WriteLineAsync(StringBuilder, CancellationToken)	Asynchronously writes the string representation of the string builder to the current string, followed by a line terminator.
WriteLineAsync(Char)	Asynchronously writes a character to the string, followed by a line terminator.
WriteLineAsync(String)	Asynchronously writes a string to the current string, followed by a line terminator.
WriteLineAsync(ReadOnlyMemory<Char>, CancellationToken)	Asynchronously writes the string representation of the memory region of characters to the current string, followed by a line terminator.
WriteLineAsync(Char[], Int32, Int32)	asynchronously writes a subarray of characters to the string, followed by a line terminator.

WriteLineAsync(StringBuilder, CancellationToken)

Source:

StringWriter.cs

Asynchronously writes the string representation of the string builder to the current string, followed by a line terminator.

C#

public override System.Threading.Tasks.Task WriteLineAsync(System.Text.StringBuilder? value, System.Threading.CancellationToken cancellationToken = default);

Parameters

value

StringBuilder

The string builder to write to the string.

cancellationToken

CancellationToken

The token to monitor for cancellation requests. The default value is None.

Returns

Task

A task that represents the asynchronous write operation.

Exceptions

OperationCanceledException

The cancellation token was canceled. This exception is stored into the returned task.

Remarks

This method stores in the task it returns all non-usage exceptions that the method's synchronous counterpart can throw. If an exception is stored into the returned task, that exception will be thrown when the task is awaited. Usage exceptions, such as ArgumentException, are still thrown synchronously. For the stored exceptions, see the exceptions thrown by WriteLine(StringBuilder).

WriteLineAsync(Char)

Source:

StringWriter.cs

Asynchronously writes a character to the string, followed by a line terminator.

C#

public override System.Threading.Tasks.Task WriteLineAsync(char value);

Parameters

value

Char

The character to write to the string.

Returns

Task

A task that represents the asynchronous write operation.

Exceptions

ObjectDisposedException

The string writer is disposed.

InvalidOperationException

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

Examples

The following example shows how to write characters by using the WriteLineAsync(Char) method.

C#

using System;
using System.Text;
using System.IO;

namespace ConsoleApplication
{
    class Program
    {
        static void Main(string[] args)
        {
            WriteCharacters();
        }

        static async void WriteCharacters()
        {
            StringBuilder stringToWrite = new StringBuilder("Characters in StringBuilder");
            stringToWrite.AppendLine();

            using (StringWriter writer = new StringWriter(stringToWrite))
            {
                UnicodeEncoding ue = new UnicodeEncoding();
                char[] charsToAdd = ue.GetChars(ue.GetBytes("and chars to add"));
                foreach (char c in charsToAdd)
                {
                    await writer.WriteLineAsync(c);
                }
                Console.WriteLine(stringToWrite.ToString());
            }
        }
    }
}
// The example displays the following output:
//
// Characters in StringBuilder
// a
// n
// d
//
// c
// h
// a
// r
// s
//
// t
// o
//
// a
// d
// d
//

Remarks

The line terminator is defined by the NewLine property.

WriteLineAsync(String)

Source:

StringWriter.cs

Asynchronously writes a string to the current string, followed by a line terminator.

C#

public override System.Threading.Tasks.Task WriteLineAsync(string? value);

Parameters

value

String

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

Returns

Task

A task that represents the asynchronous write operation.

Exceptions

ObjectDisposedException

The string writer is disposed.

InvalidOperationException

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

Examples

The following example shows how to write a string by using the WriteLineAsync(String) method.

C#

using System;
using System.Text;
using System.IO;

namespace ConsoleApplication
{
    class Program
    {
        static void Main(string[] args)
        {
            WriteCharacters();
        }

        static async void WriteCharacters()
        {
            StringBuilder stringToWrite = new StringBuilder("Characters in StringBuilder");
            stringToWrite.AppendLine();

            using (StringWriter writer = new StringWriter(stringToWrite))
            {
                await writer.WriteLineAsync("and add characters through StringWriter");
                Console.WriteLine(stringToWrite.ToString());
            }
        }
    }
}
// The example displays the following output:
//
// Characters in StringBuilder
// and add characters through StringWriter
//

Remarks

The line terminator is defined by the NewLine property.

WriteLineAsync(ReadOnlyMemory<Char>, CancellationToken)

Source:

StringWriter.cs

Asynchronously writes the string representation of the memory region of characters to the current string, followed by a line terminator.

C#

public override System.Threading.Tasks.Task WriteLineAsync(ReadOnlyMemory<char> buffer, System.Threading.CancellationToken cancellationToken = default);

Parameters

buffer

ReadOnlyMemory<Char>

A memory region of characters to write to the string.

cancellationToken

CancellationToken

The token to monitor for cancellation requests. The default value is None.

Returns

Task

A task that represents the asynchronous write operation.

Exceptions

OperationCanceledException

The cancellation token was canceled. This exception is stored into the returned task.

WriteLineAsync(Char[], Int32, Int32)

Source:

StringWriter.cs

asynchronously writes a subarray of characters to the string, followed by a line terminator.

C#

public override System.Threading.Tasks.Task WriteLineAsync(char[] buffer, int index, int count);

Parameters

buffer

Char[]

The character array to write data from.

index

Int32

The position in the buffer at which to start reading data.

count

Int32

The maximum number of characters to write.

Returns

Task

A task that represents the asynchronous write operation.

Exceptions

ArgumentNullException

buffer is null.

ArgumentException

The index plus count is greater than the buffer length.

ArgumentOutOfRangeException

index or count is negative.

ObjectDisposedException

The string writer is disposed.

InvalidOperationException

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

Examples

The following example shows how to write characters by using the WriteLineAsync(Char[], Int32, Int32) method.

C#

using System;
using System.Text;
using System.IO;

namespace ConsoleApplication
{
    class Program
    {
        static void Main(string[] args)
        {
            WriteCharacters();
        }

        static async void WriteCharacters()
        {
            StringBuilder stringToWrite = new StringBuilder("Characters in StringBuilder");
            stringToWrite.AppendLine();

            using (StringWriter writer = new StringWriter(stringToWrite))
            {
                UnicodeEncoding ue = new UnicodeEncoding();
                char[] charsToAdd = ue.GetChars(ue.GetBytes("and chars to add"));

                await writer.WriteLineAsync(charsToAdd, 0, charsToAdd.Length);

                Console.WriteLine(stringToWrite.ToString());
            }
        }
    }
}
// The example displays the following output:
//
// Characters in StringBuilder
// and chars to add
//

Remarks

The line terminator is defined by the NewLine property.