StringBuilder.Clear 方法

定義

命名空間:

System.Text

組件:

netstandard.dll, System.Runtime.dll

來源:

StringBuilder.cs

移除目前 StringBuilder 實例中的所有角色。

public:
 System::Text::StringBuilder ^ Clear();

public System.Text.StringBuilder Clear();

member this.Clear : unit -> System.Text.StringBuilder

Public Function Clear () As StringBuilder

傳回

StringBuilder

一個物件，其 Length 為0（0）。

範例

以下範例將 StringBuilder 物件實例化一個字串，呼叫該 Clear 方法，然後附加一個新的字串。

using System;
using System.Text;

public class Class1
{
   public static void Main()
   {
      StringBuilder sb = new StringBuilder("This is a string.");
      Console.WriteLine("{0} ({1} characters)", sb.ToString(), sb.Length);
      
      sb.Clear();
      Console.WriteLine("{0} ({1} characters)", sb.ToString(), sb.Length);

      sb.Append("This is a second string.");
      Console.WriteLine("{0} ({1} characters)", sb.ToString(), sb.Length);
   }
}
// The example displays the following output:
//       This is a string. (17 characters)
//        (0 characters)
//       This is a second string. (24 characters)

open System.Text

let sb = StringBuilder "This is a string."
printfn $"{sb} ({sb.Length} characters)"

sb.Clear() |> ignore
printfn $"{sb} ({sb.Length} characters)"

sb.Append "This is a second string." |> ignore
printfn $"{sb} ({sb.Length} characters)"

// The example displays the following output:
//       This is a string. (17 characters)
//        (0 characters)
//       This is a second string. (24 characters)

Imports System.Text

Module Example
   Public Sub Main()
      Dim sb As New StringBuilder("This is a string.")
      Console.WriteLine("{0} ({1} characters)", sb.ToString(), sb.Length)
      
      sb.Clear()
      Console.WriteLine("{0} ({1} characters)", sb.ToString(), sb.Length)

      sb.Append("This is a second string.")
      Console.WriteLine("{0} ({1} characters)", sb.ToString(), sb.Length)
   End Sub            
End Module
' The example displays the following output:
'       This is a string. (17 characters)
'        (0 characters)
'       This is a second string. (24 characters)

備註

Clear 是一種便利方法，等同於將當前實例的性質設 Length 為0（0）。