SecureString.SetAt(Int32, Char) Methode

Referenz

Definition

Namespace:: System.Security

Assembly:: System.Runtime.InteropServices.dll

Assembly:: netstandard.dll

Assembly:: System.Security.SecureString.dll

Assembly:: mscorlib.dll

Wichtig

Einige Informationen beziehen sich auf Vorabversionen, die vor dem Release ggf. grundlegend überarbeitet werden. Microsoft übernimmt hinsichtlich der hier bereitgestellten Informationen keine Gewährleistungen, seien sie ausdrücklich oder konkludent.

Ersetzt das an der angegebenen Indexposition vorhandene Zeichen durch ein anderes Zeichen.

public:
 void SetAt(int index, char c);

public void SetAt (int index, char c);

[System.Runtime.ExceptionServices.HandleProcessCorruptedStateExceptions]
public void SetAt (int index, char c);

member this.SetAt : int * char -> unit

[<System.Runtime.ExceptionServices.HandleProcessCorruptedStateExceptions>]
member this.SetAt : int * char -> unit

Public Sub SetAt (index As Integer, c As Char)

Parameter

index: Int32

Die Indexposition eines vorhandenen Zeichens in dieser sicheren Zeichenfolge.

c: Char

Ein Zeichen, das das vorhandene Zeichen ersetzt.

Attribute: HandleProcessCorruptedStateExceptionsAttribute

Ausnahmen

ObjectDisposedException

Diese sichere Zeichenfolge wurde bereits verworfen.

InvalidOperationException

Diese sichere Zeichenfolge ist schreibgeschützt.

ArgumentOutOfRangeException

index ist kleiner als 0 (null), größer als die Länge der sicheren Zeichenfolge oder gleich der Länge dieser Zeichenfolge.

CryptographicException

Beim Schützen oder Aufheben des Schutzes für den Wert dieser sicheren Zeichenfolge ist ein Fehler aufgetreten.

Beispiele

Im folgenden Beispiel wird veranschaulicht, wie sich die AppendChar Methoden , , , und auf den Wert eines InsertAt RemoveAt SetAt Clear SecureString -Objekts auswirken.

using namespace System;
using namespace System::Security;

void main()
{
    String^ msg = L"   The current length of the SecureString object: {0}\n";
    SecureString ^ ss = gcnew SecureString;

    Console::WriteLine(L"1) Instantiate the SecureString object:");
    Console::WriteLine(msg, ss->Length );

    Console::WriteLine(L"2) Append 'a' to the value:");
    ss->AppendChar('a');
    Console::WriteLine(msg, ss->Length );

    Console::WriteLine(L"3) Append 'X' to the value:");
    ss->AppendChar('X');
    Console::WriteLine(msg, ss->Length);

    Console::WriteLine(L"4) Append 'c' to the value:");
    ss->AppendChar('c');
    Console::WriteLine(msg, ss->Length);

    Console::WriteLine(L"5) Insert 'd' at the end of the value:");
    ss->InsertAt(ss->Length, 'd');
    Console::WriteLine(msg, ss->Length);

    Console::WriteLine(L"6) Remove the last character ('d') from the value:");
    ss->RemoveAt(3);
    Console::WriteLine(msg, ss->Length);

    Console::WriteLine(L"7) Set the second character ('X') of the value to 'b':" );
    ss->SetAt(1, 'b');
    Console::WriteLine(msg, ss->Length );

    Console::WriteLine(L"8) Delete the value of the SecureString object:");
    ss->Clear();
    Console::WriteLine(msg, ss->Length);

    delete ss;
}

/*
This code example produces the following results:

This example demonstrates the effect of the AppendChar, InsertAt,
RemoveAt, SetAt, and Clear methods on the value of a SecureString
object. This example simulates the value of the object because the
actual value is encrypted.

1) The initial value of the SecureString object:
   SecureString = ""
   Length = 0

2) AppendChar: Append 'a' to the value:
   SecureString = "a"
   Length = 1

3) AppendChar: Append 'X' to the value:
   SecureString = "aX"
   Length = 2

4) AppendChar: Append 'c' to the value:
   SecureString = "aXc"
   Length = 3

5) InsertAt: Insert 'd' at the end of the value (equivalent
     to AppendChar):
   SecureString = "aXcd"
   Length = 4

6) RemoveAt: Remove the last character ('d') from the value:
   SecureString = "aXc"
   Length = 3

7) SetAt: Set the second character ('X') of the value to 'b':
   SecureString = "abc"
   Length = 3

8) Clear: Delete the value of the SecureString object:
   SecureString = ""
   Length = 0
*/

using System;
using System.Security;

class Example
{
    public static void Main()
    {
       string msg = "The curent length of the SecureString object: {0}\n";
       Console.WriteLine("1) Instantiate the SecureString object.");
       SecureString ss = new SecureString();
       Console.WriteLine(msg, ss.Length);

       Console.WriteLine("2) Append 'a' to the value.");
       ss.AppendChar('a');
       Console.WriteLine(msg, ss.Length);

       Console.WriteLine("3) Append 'X' to the value.");
       ss.AppendChar('X');
       Console.WriteLine(msg, ss.Length);

       Console.WriteLine("4) Append 'c' to the value.");
       ss.AppendChar('c');
       Console.WriteLine(msg, ss.Length);

       Console.WriteLine("5) Insert 'd' at the end of the value.");
       ss.InsertAt(ss.Length, 'd');
       Console.WriteLine(msg, ss.Length);

       Console.WriteLine("6) Remove the last character ('d') from the value.");
       ss.RemoveAt(3);
       Console.WriteLine(msg, ss.Length);

       Console.WriteLine("7) Set the second character of the value to 'b'.");
       ss.SetAt(1, 'b');
       Console.WriteLine(msg, ss.Length);

       Console.WriteLine("8) Delete the value of the SecureString object:");
       ss.Clear();
       Console.WriteLine(msg, ss.Length);

       ss.Dispose();
    }
}
// The example displays the following output:
//       1) Instantiate the SecureString object.
//       The curent length of the SecureString object: 0
//
//       2) Append 'a' to the value.
//       The curent length of the SecureString object: 1
//
//       3) Append 'X' to the value.
//       The curent length of the SecureString object: 2
//
//       4) Append 'c' to the value.
//       The curent length of the SecureString object: 3
//
//       5) Insert 'd' at the end of the value.
//       The curent length of the SecureString object: 4
//
//       6) Remove the last character ('d') from the value.
//       The curent length of the SecureString object: 3
//
//       7) Set the second character of the value to 'b'.
//       The curent length of the SecureString object: 3
//
//       8) Delete the value of the SecureString object:
//       The curent length of the SecureString object: 0

Imports System.Security

Module Example
    Public Sub Main()
       Dim msg As String = "The curent length of the SecureString object: {0}" + vbCrLf
       Console.WriteLine("1) Instantiate the SecureString object.")
       Dim ss As New SecureString()
       Console.WriteLine(msg, ss.Length)

       Console.WriteLine("2) Append 'a' to the value.")
       ss.AppendChar("a"c)
       Console.WriteLine(msg, ss.Length)

       Console.WriteLine("3) Append 'X' to the value.")
       ss.AppendChar("X"c)
       Console.WriteLine(msg, ss.Length)

       Console.WriteLine("4) Append 'c' to the value.")
       ss.AppendChar("c"c)
       Console.WriteLine(msg, ss.Length)

       Console.WriteLine("5) Insert 'd' at the end of the value.")
       ss.InsertAt(ss.Length, "d"c)
       Console.WriteLine(msg, ss.Length)

       Console.WriteLine("6) Remove the last character ('d') from the value.")
       ss.RemoveAt(3)
       Console.WriteLine(msg, ss.Length)

       Console.WriteLine("7) Set the second character of the value to 'b'.")
       ss.SetAt(1, "b"c)
       Console.WriteLine(msg, ss.Length)

       Console.WriteLine("8) Delete the value of the SecureString object:")
       ss.Clear()
       Console.WriteLine(msg, ss.Length)

       ss.Dispose()
    End Sub
End Module
' The example displays the following output:
'       1) Instantiate the SecureString object.
'       The curent length of the SecureString object: 0
'
'       2) Append 'a' to the value.
'       The curent length of the SecureString object: 1
'
'       3) Append 'X' to the value.
'       The curent length of the SecureString object: 2
'
'       4) Append 'c' to the value.
'       The curent length of the SecureString object: 3
'
'       5) Insert 'd' at the end of the value.
'       The curent length of the SecureString object: 4
'
'       6) Remove the last character ('d') from the value.
'       The curent length of the SecureString object: 3
'
'       7) Set the second character of the value to 'b'.
'       The curent length of the SecureString object: 3
'
'       8) Delete the value of the SecureString object:
'       The curent length of the SecureString object: 0

Hinweise

Der Index ist nullbasiert. Das erste Zeichen in dieser Instanz befindet sich an Indexposition 0 (null).

Wenn die Implementierung einen Schutzmechanismus verwendet, z. B. verschlüsselung, ist der Wert der sicheren Zeichenfolge, falls vorhanden, ungeschützter Wert. c wird der angegebenen Indexposition zugewiesen. Anschließend wird der neue Wert erneut geschützt.

Gilt für