StringBuilder.Length Właściwość

Definicja

Przestrzeń nazw:

System.Text

Zestaw:

System.Runtime.dll

Źródło:

StringBuilder.cs

Pobiera lub ustawia długość bieżącego StringBuilder obiektu.

public:
 property int Length { int get(); void set(int value); };

public int Length { get; set; }

member this.Length : int with get, set

Public Property Length As Integer

Wartość właściwości

Int32

Długość tego wystąpienia.

Wyjątki

ArgumentOutOfRangeException

Wartość określona dla operacji zestawu jest mniejsza niż zero lub większa niż MaxCapacity.

Przykłady

W poniższym przykładzie pokazano Length właściwość .

using namespace System;
using namespace System::Text;
int main()
{
   StringBuilder^ sb1 = gcnew StringBuilder( "abc" );
   StringBuilder^ sb2 = gcnew StringBuilder( "abc",16 );
   Console::WriteLine();
   Console::WriteLine( "a1) sb1->Length = {0}, sb1->Capacity = {1}", sb1->Length, sb1->Capacity );
   Console::WriteLine( "a2) sb2->Length = {0}, sb2->Capacity = {1}", sb2->Length, sb2->Capacity );
   Console::WriteLine( "a3) sb1 = \"{0}\", sb2 = \"{1}\"", sb1, sb2 );
   Console::WriteLine( "a4) sb1 equals sb2: {0}", sb1->Equals( sb2 ) );
   Console::WriteLine();
   Console::WriteLine( "Ensure sb1 has a capacity of at least 50 characters." );
   sb1->EnsureCapacity( 50 );
   Console::WriteLine();
   Console::WriteLine( "b1) sb1->Length = {0}, sb1->Capacity = {1}", sb1->Length, sb1->Capacity );
   Console::WriteLine( "b2) sb2->Length = {0}, sb2->Capacity = {1}", sb2->Length, sb2->Capacity );
   Console::WriteLine( "b3) sb1 = \"{0}\", sb2 = \"{1}\"", sb1, sb2 );
   Console::WriteLine( "b4) sb1 equals sb2: {0}", sb1->Equals( sb2 ) );
   Console::WriteLine();
   Console::WriteLine( "Set the length of sb1 to zero." );
   Console::WriteLine( "Set the capacity of sb2 to 51 characters." );
   sb1->Length = 0;
   sb2->Capacity = 51;
   Console::WriteLine();
   Console::WriteLine( "c1) sb1->Length = {0}, sb1->Capacity = {1}", sb1->Length, sb1->Capacity );
   Console::WriteLine( "c2) sb2->Length = {0}, sb2->Capacity = {1}", sb2->Length, sb2->Capacity );
   Console::WriteLine( "c3) sb1 = \"{0}\", sb2 = \"{1}\"", sb1, sb2 );
   Console::WriteLine( "c4) sb1 equals sb2: {0}", sb1->Equals( sb2 ) );
}

/*
The example displays the following output:

a1) sb1->Length = 3, sb1->Capacity = 16
a2) sb2->Length = 3, sb2->Capacity = 16
a3) sb1 = "abc", sb2 = "abc"
a4) sb1 equals sb2: True

Ensure sb1 has a capacity of at least 50 characters.

b1) sb1->Length = 3, sb1->Capacity = 50
b2) sb2->Length = 3, sb2->Capacity = 16
b3) sb1 = "abc", sb2 = "abc"
b4) sb1 equals sb2: False

Set the length of sb1 to zero.
Set the capacity of sb2 to 51 characters.

c1) sb1->Length = 0, sb1->Capacity = 50
c2) sb2->Length = 3, sb2->Capacity = 51
c3) sb1 = "", sb2 = "abc"
c4) sb1 equals sb2: False
*/

using System;
using System.Text;

class Sample
{
    public static void Main()
    {
    StringBuilder sb1 = new StringBuilder("abc");
    StringBuilder sb2 = new StringBuilder("abc", 16);

    Console.WriteLine();
    Console.WriteLine("a1) sb1.Length = {0}, sb1.Capacity = {1}", sb1.Length, sb1.Capacity);
    Console.WriteLine("a2) sb2.Length = {0}, sb2.Capacity = {1}", sb2.Length, sb2.Capacity);
    Console.WriteLine("a3) sb1.ToString() = \"{0}\", sb2.ToString() = \"{1}\"",
                           sb1.ToString(),       sb2.ToString());
    Console.WriteLine("a4) sb1 equals sb2: {0}", sb1.Equals(sb2));

    Console.WriteLine();
    Console.WriteLine("Ensure sb1 has a capacity of at least 50 characters.");
    sb1.EnsureCapacity(50);

    Console.WriteLine();
    Console.WriteLine("b1) sb1.Length = {0}, sb1.Capacity = {1}", sb1.Length, sb1.Capacity);
    Console.WriteLine("b2) sb2.Length = {0}, sb2.Capacity = {1}", sb2.Length, sb2.Capacity);
    Console.WriteLine("b3) sb1.ToString() = \"{0}\", sb2.ToString() = \"{1}\"",
                           sb1.ToString(),       sb2.ToString());
    Console.WriteLine("b4) sb1 equals sb2: {0}", sb1.Equals(sb2));

    Console.WriteLine();
    Console.WriteLine("Set the length of sb1 to zero.");
    Console.WriteLine("Set the capacity of sb2 to 51 characters.");
    sb1.Length = 0;
    sb2.Capacity = 51;

    Console.WriteLine();
    Console.WriteLine("c1) sb1.Length = {0}, sb1.Capacity = {1}", sb1.Length, sb1.Capacity);
    Console.WriteLine("c2) sb2.Length = {0}, sb2.Capacity = {1}", sb2.Length, sb2.Capacity);
    Console.WriteLine("c3) sb1.ToString() = \"{0}\", sb2.ToString() = \"{1}\"",
                           sb1.ToString(),       sb2.ToString());
    Console.WriteLine("c4) sb1 equals sb2: {0}", sb1.Equals(sb2));
    }
}
/*
The example displays the following output:

a1) sb1.Length = 3, sb1.Capacity = 16
a2) sb2.Length = 3, sb2.Capacity = 16
a3) sb1.ToString() = "abc", sb2.ToString() = "abc"
a4) sb1 equals sb2: True

Ensure sb1 has a capacity of at least 50 characters.

b1) sb1.Length = 3, sb1.Capacity = 50
b2) sb2.Length = 3, sb2.Capacity = 16
b3) sb1.ToString() = "abc", sb2.ToString() = "abc"
b4) sb1 equals sb2: False

Set the length of sb1 to zero.
Set the capacity of sb2 to 51 characters.

c1) sb1.Length = 0, sb1.Capacity = 50
c2) sb2.Length = 3, sb2.Capacity = 51
c3) sb1.ToString() = "", sb2.ToString() = "abc"
c4) sb1 equals sb2: False
*/

open System.Text

let sb1 = StringBuilder "abc"
let sb2 = StringBuilder("abc", 16)

printfn $"a1) sb1.Length = {sb1.Length}, sb1.Capacity = {sb1.Capacity}"
printfn $"a2) sb2.Length = {sb2.Length}, sb2.Capacity = {sb2.Capacity}"
printfn $"a3) sb1.ToString() = \"{sb1}\", sb2.ToString() = \"{sb2}\""
printfn $"a4) sb1 equals sb2: {sb1.Equals sb2}"

printfn "\nEnsure sb1 has a capacity of at least 50 characters."
sb1.EnsureCapacity 50 |> ignore

printfn $"\nb1) sb1.Length = {sb1.Length}, sb1.Capacity = {sb1.Capacity}"
printfn $"b2) sb2.Length = {sb2.Length}, sb2.Capacity = {sb2.Capacity}"
printfn $"b3) sb1.ToString() = \"{sb1}\", sb2.ToString() = \"{sb2}\""
printfn $"b4) sb1 equals sb2: {sb1.Equals sb2}"

printfn "\nSet the length of sb1 to zero."
printfn "Set the capacity of sb2 to 51 characters."
sb1.Length <- 0
sb2.Capacity <- 51

printfn $"\nc1) sb1.Length = {sb1.Length}, sb1.Capacity = {sb1.Capacity}"
printfn $"c2) sb2.Length = {sb2.Length}, sb2.Capacity = {sb2.Capacity}"
printfn $"c3) sb1.ToString() = \"{sb1}\", sb2.ToString() = \"{sb2}\""
printfn $"c4) sb1 equals sb2: {sb1.Equals sb2}"

// The example displays the following output:
//       a1) sb1.Length = 3, sb1.Capacity = 16
//       a2) sb2.Length = 3, sb2.Capacity = 16
//       a3) sb1.ToString() = "abc", sb2.ToString() = "abc"
//       a4) sb1 equals sb2: True
//
//       Ensure sb1 has a capacity of at least 50 characters.
//       
//       b1) sb1.Length = 3, sb1.Capacity = 50
//       b2) sb2.Length = 3, sb2.Capacity = 16
//       b3) sb1.ToString() = "abc", sb2.ToString() = "abc"
//       b4) sb1 equals sb2: False
//       
//       Set the length of sb1 to zero.
//       Set the capacity of sb2 to 51 characters.
//       
//       c1) sb1.Length = 0, sb1.Capacity = 50
//       c2) sb2.Length = 3, sb2.Capacity = 51
//       c3) sb1.ToString() = "", sb2.ToString() = "abc"
//       c4) sb1 equals sb2: False

Imports System.Text

Class Sample
   Public Shared Sub Main()
      Dim sb1 As New StringBuilder("abc")
      Dim sb2 As New StringBuilder("abc", 16)
      
      Console.WriteLine()
      Console.WriteLine("a1) sb1.Length = {0}, sb1.Capacity = {1}", sb1.Length, sb1.Capacity)
      Console.WriteLine("a2) sb2.Length = {0}, sb2.Capacity = {1}", sb2.Length, sb2.Capacity)
      Console.WriteLine("a3) sb1.ToString() = ""{0}"", sb2.ToString() = ""{1}""", _
                             sb1.ToString(),           sb2.ToString())
      Console.WriteLine("a4) sb1 equals sb2: {0}", sb1.Equals(sb2))
      
      Console.WriteLine()
      Console.WriteLine("Ensure sb1 has a capacity of at least 50 characters.")
      sb1.EnsureCapacity(50)
      
      Console.WriteLine()
      Console.WriteLine("b1) sb1.Length = {0}, sb1.Capacity = {1}", sb1.Length, sb1.Capacity)
      Console.WriteLine("b2) sb2.Length = {0}, sb2.Capacity = {1}", sb2.Length, sb2.Capacity)
      Console.WriteLine("b3) sb1.ToString() = ""{0}"", sb2.ToString() = ""{1}""", _
                             sb1.ToString(),           sb2.ToString())
      Console.WriteLine("b4) sb1 equals sb2: {0}", sb1.Equals(sb2))
      
      Console.WriteLine()
      Console.WriteLine("Set the length of sb1 to zero.")
      Console.WriteLine("Set the capacity of sb2 to 51 characters.")
      sb1.Length = 0
      sb2.Capacity = 51
      
      Console.WriteLine()
      Console.WriteLine("c1) sb1.Length = {0}, sb1.Capacity = {1}", sb1.Length, sb1.Capacity)
      Console.WriteLine("c2) sb2.Length = {0}, sb2.Capacity = {1}", sb2.Length, sb2.Capacity)
      Console.WriteLine("c3) sb1.ToString() = ""{0}"", sb2.ToString() = ""{1}""", _
                             sb1.ToString(),           sb2.ToString())
      Console.WriteLine("c4) sb1 equals sb2: {0}", sb1.Equals(sb2))
   End Sub 
End Class
'The example displays the following output:
'       a1) sb1.Length = 3, sb1.Capacity = 16
'       a2) sb2.Length = 3, sb2.Capacity = 16
'       a3) sb1.ToString() = "abc", sb2.ToString() = "abc"
'       a4) sb1 equals sb2: True
'       
'       Ensure sb1 has a capacity of at least 50 characters.
'       
'       b1) sb1.Length = 3, sb1.Capacity = 50
'       b2) sb2.Length = 3, sb2.Capacity = 16
'       b3) sb1.ToString() = "abc", sb2.ToString() = "abc"
'       b4) sb1 equals sb2: False
'       
'       Set the length of sb1 to zero.
'       Set the capacity of sb2 to 51 characters.
'       
'       c1) sb1.Length = 0, sb1.Capacity = 50
'       c2) sb2.Length = 3, sb2.Capacity = 51
'       c3) sb1.ToString() = "", sb2.ToString() = "abc"
'       c4) sb1 equals sb2: False

Uwagi

Długość StringBuilder obiektu jest definiowana przez jego liczbę Char obiektów.

String.Length Podobnie jak właściwość, Length właściwość wskazuje długość bieżącego obiektu ciągu. String.Length W przeciwieństwie do właściwości , która jest tylko do odczytu, Length właściwość umożliwia modyfikowanie długości ciągu przechowywanego w StringBuilder obiekcie.

Jeśli określona długość jest mniejsza niż bieżąca długość, bieżący StringBuilder obiekt jest obcinany do określonej długości. Jeśli określona długość jest większa niż bieżąca długość, koniec wartości ciągu bieżącego StringBuilder obiektu jest wypełniony znakiem NULL Unicode (U+0000).

Jeśli określona długość jest większa niż bieżąca pojemność, Capacity zwiększa się tak, aby była większa lub równa określonej długości.