SecureString.Clear 메서드
정의
중요
일부 정보는 릴리스되기 전에 상당 부분 수정될 수 있는 시험판 제품과 관련이 있습니다. Microsoft는 여기에 제공된 정보에 대해 어떠한 명시적이거나 묵시적인 보증도 하지 않습니다.
현재 보안 문자열의 값을 삭제합니다.
public:
void Clear();
public void Clear ();
member this.Clear : unit -> unit
Public Sub Clear ()
예외
이 보안 문자열이 이미 삭제된 경우
이 보안 문자열이 읽기 전용인 경우
예제
다음 예제에서는 AppendChar ,, InsertAt RemoveAt , SetAt 및 Clear 메서드가 개체의 값에 영향을 주는 SecureString 방법을 보여 줍니다.
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
설명
이 보안 문자열의 값을 포함 하는 컴퓨터 메모리를 0으로 설정 하면이 보안 문자열의 값 길이가 0으로 설정 됩니다.