StringBuilder.Length Eigenschap

Definitie

Naamruimte:: System.Text

Assembly's:: mscorlib.dll, System.Runtime.dll

Assembly's:: netstandard.dll, System.Runtime.dll

Assembly:: System.Runtime.dll

Assembly:: mscorlib.dll

Assembly:: netstandard.dll

Bron:: StringBuilder.cs

Bron:: StringBuilder.cs

Bron:: StringBuilder.cs

Bron:: StringBuilder.cs

Bron:: StringBuilder.cs

Belangrijk

Bepaalde informatie heeft betrekking op een voorlopige productversie die aanzienlijk kan worden gewijzigd voordat deze wordt uitgebracht. Microsoft biedt geen enkele expliciete of impliciete garanties met betrekking tot de informatie die hier wordt verstrekt.

Hiermee wordt de lengte van het huidige StringBuilder object opgehaald of ingesteld.

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

Waarde van eigenschap

Int32

De lengte van dit exemplaar.

Uitzonderingen

ArgumentOutOfRangeException

De opgegeven waarde voor een setbewerking is kleiner dan nul of groter dan MaxCapacity.

Voorbeelden

In het volgende voorbeeld ziet u de Length eigenschap.

using System;
using System.Text;

StringBuilder sb1 = new("abc");
StringBuilder sb2 = new("abc", 16);

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

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

Console.WriteLine();
Console.WriteLine($"b1) sb1.Length = {sb1.Length}, sb1.Capacity = {sb1.Capacity}");
Console.WriteLine($"b2) sb2.Length = {sb2.Length}, sb2.Capacity = {sb2.Capacity}");
Console.WriteLine($"b3) sb1.ToString() = \"{sb1}\", sb2.ToString() = \"{sb2}\"");
Console.WriteLine($"b4) sb1 equals sb2: {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($"c1) sb1.Length = {sb1.Length}, sb1.Capacity = {sb1.Capacity}");
Console.WriteLine($"c2) sb2.Length = {sb2.Length}, sb2.Capacity = {sb2.Capacity}");
Console.WriteLine($"c3) sb1.ToString() = \"{sb1}\", sb2.ToString() = \"{sb2}\"");
Console.WriteLine($"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: True (False on .NET Framework)

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: True (False on .NET Framework)
//       
//       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: True (False on .NET Framework)
'       
'       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

Opmerkingen

De lengte van een StringBuilder object wordt gedefinieerd door het aantal Char objecten.

Net als bij de String.Length eigenschap geeft de Length eigenschap de lengte van het huidige tekenreeksobject aan. In tegenstelling tot de String.Length eigenschap, die alleen-lezen is, kunt u met de Length eigenschap de lengte van de tekenreeks wijzigen die is opgeslagen in het StringBuilder object.

Als de opgegeven lengte kleiner is dan de huidige lengte, wordt het huidige StringBuilder object afgekapt tot de opgegeven lengte. Als de opgegeven lengte groter is dan de huidige lengte, wordt het einde van de tekenreekswaarde van het huidige StringBuilder object opgevuld met het Unicode NULL-teken (U+0000).

Als de opgegeven lengte groter is dan de huidige capaciteit, Capacity neemt deze toe zodat deze groter is dan of gelijk is aan de opgegeven lengte.

Van toepassing op

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