StringWriter.WriteAsync 方法

参考

定义

命名空间:: System.IO

程序集:: System.IO.dll

程序集:: System.Runtime.dll

程序集:: System.Runtime.Extensions.dll

程序集:: mscorlib.dll

程序集:: netstandard.dll

重要

一些信息与预发行产品相关，相应产品在发行之前可能会进行重大修改。对于此处提供的信息，Microsoft 不作任何明示或暗示的担保。

以异步方式将数据写入字符串。

重载

WriteAsync(Char)	将字符异步写入该字符串。
WriteAsync(String)	将字符串异步写入当前字符串。
WriteAsync(ReadOnlyMemory<Char>, CancellationToken)	将字符的内存区域异步写入字符串。
WriteAsync(StringBuilder, CancellationToken)	将字符串生成器的文本表示形式异步写入字符串。
WriteAsync(Char[], Int32, Int32)	将字符的子数组异步写入字符串。

WriteAsync(Char)

Source:: StringWriter.cs

Source:: StringWriter.cs

Source:: StringWriter.cs

将字符异步写入该字符串。

public:
 override System::Threading::Tasks::Task ^ WriteAsync(char value);

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

[System.Runtime.InteropServices.ComVisible(false)]
public override System.Threading.Tasks.Task WriteAsync (char value);

override this.WriteAsync : char -> System.Threading.Tasks.Task

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

Public Overrides Function WriteAsync (value As Char) As Task

参数

value: Char

要写入字符串中的字符。

Task

表示异步写入操作的任务。

属性: ComVisibleAttribute

例外

ObjectDisposedException

已释放字符串编写器。

InvalidOperationException

字符串编写器正在由前一个写操作使用。

示例

以下示例演示如何使用 WriteAsync(Char) 方法编写字符。

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.WriteAsync(c);
                }
                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"))
            For Each c As Char In charsToAdd
                Await writer.WriteAsync(c)
            Next
            Console.WriteLine(stringToWrite.ToString())
        End Using
    End Sub
End Module
' The example displays the following output:
'
' Characters in StringBuilder
' and chars to add
'

注解

此方法将存储在任务中，它返回该方法的同步对应项可能引发的所有非使用异常。如果异常存储在返回的任务中，则在等待任务时将引发该异常。使用异常（如 ArgumentException）仍会同步引发。有关存储的异常，请参阅引发的 Write(Char)异常。

适用于

WriteAsync(String)

Source:: StringWriter.cs

Source:: StringWriter.cs

Source:: StringWriter.cs

将字符串异步写入当前字符串。

public:
 override System::Threading::Tasks::Task ^ WriteAsync(System::String ^ value);

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

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

[System.Runtime.InteropServices.ComVisible(false)]
public override System.Threading.Tasks.Task WriteAsync (string value);

override this.WriteAsync : string -> System.Threading.Tasks.Task

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

Public Overrides Function WriteAsync (value As String) As Task

参数

value: String

要写入的字符串。如果 value 为 null，则不会将任何内容写入文本流。

Task

表示异步写入操作的任务。

属性: ComVisibleAttribute

例外

ObjectDisposedException

已释放字符串编写器。

InvalidOperationException

字符串编写器正在由前一个写操作使用。

示例

以下示例演示如何使用 WriteAsync(String) 方法编写字符串。

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.WriteAsync("and add characters through StringWriter");
                Console.WriteLine(stringToWrite.ToString());
            }
        }
    }
}
// The example displays the following output:
//
// Characters in StringBuilder
// and add characters through StringWriter
//

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)
            Await writer.WriteAsync("and add characters through StringWriter")
            Console.WriteLine(stringToWrite.ToString())
        End Using
    End Sub
End Module
' The example displays the following output:
'
' Characters in StringBuilder
' and add characters through StringWriter
'

注解

此方法将存储在任务中，它返回该方法的同步对应项可能引发的所有非使用异常。如果异常存储在返回的任务中，则在等待任务时将引发该异常。使用异常（如 ArgumentException）仍会同步引发。有关存储的异常，请参阅引发的 Write(String)异常。

适用于

WriteAsync(ReadOnlyMemory<Char>, CancellationToken)

Source:: StringWriter.cs

Source:: StringWriter.cs

Source:: StringWriter.cs

将字符的内存区域异步写入字符串。

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

override this.WriteAsync : ReadOnlyMemory<char> * System.Threading.CancellationToken -> System.Threading.Tasks.Task

Public Overrides Function WriteAsync (buffer As ReadOnlyMemory(Of Char), Optional cancellationToken As CancellationToken = Nothing) As Task

参数

buffer: ReadOnlyMemory<Char>

要写入字符串中的字符内存区域。

cancellationToken: CancellationToken

要监视取消请求的标记。默认值为 None。

Task

表示异步写入操作的任务。

例外

OperationCanceledException

取消令牌已取消。此异常存储在返回的任务中。

适用于

WriteAsync(StringBuilder, CancellationToken)

Source:: StringWriter.cs

Source:: StringWriter.cs

Source:: StringWriter.cs

将字符串生成器的文本表示形式异步写入字符串。

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

override this.WriteAsync : System.Text.StringBuilder * System.Threading.CancellationToken -> System.Threading.Tasks.Task

Public Overrides Function WriteAsync (value As StringBuilder, Optional cancellationToken As CancellationToken = Nothing) As Task

参数

value: StringBuilder

要写入字符串的字符串生成器。

cancellationToken: CancellationToken

要监视取消请求的标记。默认值为 None。

Task

表示异步写入操作的任务。

例外

OperationCanceledException

取消令牌已取消。此异常存储在返回的任务中。

注解

此方法将存储在任务中，它返回该方法的同步对应项可能引发的所有非使用异常。如果异常存储在返回的任务中，则在等待任务时将引发该异常。使用异常（如 ArgumentException）仍会同步引发。有关存储的异常，请参阅引发的 Write(StringBuilder)异常。

适用于

WriteAsync(Char[], Int32, Int32)

Source:: StringWriter.cs

Source:: StringWriter.cs

Source:: StringWriter.cs

将字符的子数组异步写入字符串。

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

参数

buffer: Char[]

要从中写出数据的字符数组。

index: Int32

缓冲区中开始读取数据的位置。

count: Int32

要写入的最大字符数。

Task

表示异步写入操作的任务。

属性: ComVisibleAttribute

例外

ArgumentNullException

buffer 为 null。

ArgumentException

index 加 count 大于缓冲区长度。

ArgumentOutOfRangeException

index 或 count 为负数。

ObjectDisposedException

已释放字符串编写器。

InvalidOperationException

字符串编写器正在由前一个写操作使用。

示例

以下示例演示如何使用 WriteAsync(Char[], Int32, Int32) 方法编写字符。

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
'

注解

此方法将存储在任务中，它返回该方法的同步对应项可能引发的所有非使用异常。如果异常存储在返回的任务中，则在等待任务时将引发该异常。使用异常（如 ArgumentException）仍会同步引发。有关存储的异常，请参阅引发的 Write(Char[], Int32, Int32)异常。

适用于

通过

StringWriter.WriteAsync 方法

定义

重载

WriteAsync(Char)

参数

返回

例外

示例

注解

适用于

WriteAsync(String)

参数

返回

例外

示例

注解

适用于

WriteAsync(ReadOnlyMemory<Char>, CancellationToken)

参数

返回

例外

适用于

WriteAsync(StringBuilder, CancellationToken)

参数

返回

例外

注解

适用于

WriteAsync(Char[], Int32, Int32)

参数

返回

例外

示例

注解

适用于

其他资源