StringWriter.WriteAsync Method (System.IO) (original) (raw)

Source:

StringWriter.cs

Source:

StringWriter.cs

Source:

StringWriter.cs

Source:

StringWriter.cs

Writes a subarray of characters to the string asynchronously.

public:
 override System::Threading::Tasks::Task ^ WriteAsync(cli::array <char> ^ buffer, int index, int count);

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

[System.Runtime.InteropServices.ComVisible(false)]
public override System.Threading.Tasks.Task WriteAsync(char[] buffer, int index, int count);

override this.WriteAsync : char[] * int * int -> System.Threading.Tasks.Task

[<System.Runtime.InteropServices.ComVisible(false)>]
override this.WriteAsync : char[] * int * int -> System.Threading.Tasks.Task

Public Overrides Function WriteAsync (buffer As Char(), index As Integer, count As Integer) As Task

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

A task that represents the asynchronous write operation.

Attributes

Exceptions

The index plus count is greater than the buffer length.

index or count is negative.

The string writer is disposed.

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

Examples

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

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.WriteAsync(charsToAdd, 0, charsToAdd.Length);

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

Imports System.IO
Imports System.Text

Module Module1

    Sub Main()
        WriteCharacters()
    End Sub

    Async Sub WriteCharacters()
        Dim stringToWrite As StringBuilder = New StringBuilder("Characters in StringBuilder")
        stringToWrite.AppendLine()

        Using writer As StringWriter = New StringWriter(stringToWrite)

            Dim ue As UnicodeEncoding = New UnicodeEncoding()
            Dim charsToAdd() = ue.GetChars(ue.GetBytes("and chars to add"))

            Await writer.WriteAsync(charsToAdd, 0, charsToAdd.Length)

            Console.WriteLine(stringToWrite.ToString())
        End Using
    End Sub
End Module
' The example displays the following output:
'
' Characters in StringBuilder
' and chars to add
'

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 Write(Char[], Int32, Int32).

Applies to