String.Length 屬性

定義

命名空間:

System

組件:

System.Runtime.dll

組件:

netstandard.dll

組件:

mscorlib.dll

取得目前 String 物件中字元的數目。

public:
 property int Length { int get(); };

public int Length { get; }

member this.Length : int

Public ReadOnly Property Length As Integer

屬性值

Int32

目前字串中的字元數。

範例

下列範例會示範 Length 屬性。

// Sample for String::Length
using namespace System;
int main()
{
   String^ str = "abcdefg";
   Console::WriteLine( "1) The length of '{0}' is {1}", str, str->Length );
   Console::WriteLine( "2) The length of '{0}' is {1}", "xyz", ((String^)"xyz")->Length );
   int length = str->Length;
   Console::WriteLine( "1) The length of '{0}' is {1}", str, length );
}

/*
This example displays the following output:
   1) The length of 'abcdefg' is 7
   2) The length of 'xyz' is 3
   3) The length of 'abcdefg' is 7
*/

string str = "abcdefg";
Console.WriteLine("1) The length of '{0}' is {1}", str, str.Length);
Console.WriteLine("2) The length of '{0}' is {1}", "xyz", "xyz".Length);

int length = str.Length;
Console.WriteLine("3) The length of '{0}' is {1}", str, length);

// This example displays the following output:
//    1) The length of 'abcdefg' is 7
//    2) The length of 'xyz' is 3
//    3) The length of 'abcdefg' is 7

Class Sample
   Public Shared Sub Main()
      Dim str As String = "abcdefg"
      Console.WriteLine("1) The length of '{0}' is {1}", str, str.Length)
      Console.WriteLine("2) The length of '{0}' is {1}", "xyz", "xyz".Length)
      Dim length As Integer = str.Length
      Console.WriteLine("1) The length of '{0}' is {1}", str, length)
   End Sub
End Class
'
'This example displays the following output:
'    1) The length of 'abcdefg' is 7
'    2) The length of 'xyz' is 3
'    3) The length of 'abcdefg' is 7

備註

Length屬性 Char 會傳回這個實例中的物件數目，而不是 Unicode 字元數。 原因是 Unicode 字元可能會以一個以上的字元表示 Char 。 使用 System.Globalization.StringInfo 類別來處理每個 Unicode 字元，而不是每個字元 Char 。

在某些語言中，例如 C 和 c + +，null 字元表示字串的結尾。 在 .NET 中，null 字元可以內嵌在字串中。 當字串包含一或多個 null 字元時，它們會包含在總字串的長度中。 例如，在下列字串中，子字串 "abc" 和 "def" 會以 null 字元分隔。 Length屬性會傳回7，表示它包含六個字母字元以及 null 字元。

using namespace System;
using namespace System::Text;

void main()
{
   String^ characters = "abc" + L'0' + "def";
   Console::WriteLine(characters->Length);        // Displays 7
}

string characters = "abc\u0000def";
Console.WriteLine(characters.Length); // Displays 7

Imports System.Text

Module Example

   Public Sub Main()
      Dim characters As String = "abc" + ChrW(0) + "def"
      Console.WriteLine(characters.Length)       ' Displays 7
   End Sub
End Module

另請參閱

• Int32