Marshal.ZeroFreeCoTaskMemAnsi(IntPtr) 메서드

정의

SecureStringToCoTaskMemAnsi(SecureString) 메서드를 사용하여 할당한 관리되지 않는 문자열 포인터를 해제합니다.Frees an unmanaged string pointer that was allocated using the SecureStringToCoTaskMemAnsi(SecureString) method.

public:
 static void ZeroFreeCoTaskMemAnsi(IntPtr s);
[System.Security.SecurityCritical]
public static void ZeroFreeCoTaskMemAnsi (IntPtr s);
public static void ZeroFreeCoTaskMemAnsi (IntPtr s);
[<System.Security.SecurityCritical>]
static member ZeroFreeCoTaskMemAnsi : nativeint -> unit
static member ZeroFreeCoTaskMemAnsi : nativeint -> unit
Public Shared Sub ZeroFreeCoTaskMemAnsi (s As IntPtr)

매개 변수

s
IntPtr

해제할 관리되지 않는 문자열의 주소입니다.The address of the unmanaged string to free.

특성

예제

다음 예제에서는 메서드를 사용 하 여 SecureStringToCoTaskMemAnsi 개체의 내용을 SecureString 관리 되지 않는 메모리 블록으로 마샬링하고 해독 합니다.The following example uses the SecureStringToCoTaskMemAnsi method to marshal and decrypt the contents of a SecureString object to a block of unmanaged memory. 그런 다음 메서드를 사용 하 여 ZeroFreeCoTaskMemAnsi 관리 되지 않는 블록을 삭제 하 고 삭제 합니다.It then uses the ZeroFreeCoTaskMemAnsi method to zero out and dispose the unmanaged block.

using System;
using System.Runtime.InteropServices;
using System.Security;

class MarshalExample
{
     static void Main()
     {
         IntPtr unmanagedRef = IntPtr.Zero;

          // Ask the user for a password.
          Console.Write("Please enter your password: ");

          SecureString passWord = GetPassword();

          Console.WriteLine("Copying and decrypting the string to unmanaged memory...");

          // Copy the Secure string to unmanaged memory (and decrypt it).
          unmanagedRef = Marshal.SecureStringToCoTaskMemAnsi(passWord);

          if (unmanagedRef != IntPtr.Zero)
          {
              Console.WriteLine("Zeroing out unmanaged memory...");

              Marshal.ZeroFreeCoTaskMemAnsi(unmanagedRef);
          }
          passWord.Dispose();

         Console.WriteLine("Done.");
     }

     public static SecureString GetPassword()
     {
         SecureString password = new SecureString();

         // get the first character of the password
         ConsoleKeyInfo nextKey = Console.ReadKey(true);

         while (nextKey.Key != ConsoleKey.Enter)
         {
             if (nextKey.Key == ConsoleKey.Backspace)
             {
                 if (password.Length > 0)
                 {
                     password.RemoveAt(password.Length - 1);

                     // erase the last * as well
                     Console.Write(nextKey.KeyChar);
                     Console.Write(" ");
                     Console.Write(nextKey.KeyChar);
                 }
             }
             else
             {
                 password.AppendChar(nextKey.KeyChar);
                 Console.Write("*");
             }

             nextKey = Console.ReadKey(true);
         }

         Console.WriteLine();

         // lock the password down
         password.MakeReadOnly();
         return password;
     }
}
Imports System.Runtime.InteropServices
Imports System.Security

Module Example
    Sub Main()
        Dim unmanagedRef As IntPtr

         ' Ask the user for a password.
         Console.Write("Please enter your password: ")
         Dim passWord As SecureString = GetPassword()

         Console.WriteLine("Copying and decrypting the string to unmanaged memory...")

         ' Copy the Secure string to unmanaged memory (and decrypt it).
         unmanagedRef = Marshal.SecureStringToCoTaskMemAnsi(passWord)

         If unmanagedRef <> IntPtr.Size Then
             Console.WriteLine("Zeroing out unmanaged memory...")
             Marshal.ZeroFreeCoTaskMemAnsi(unmanagedRef)
         End If
         passWord.Dispose()

        Console.WriteLine("Done.")
    End Sub



    Function GetPassword() As SecureString
        Dim password As New SecureString()

        ' get the first character of the password
        Dim nextKey As ConsoleKeyInfo = Console.ReadKey(True)

        While nextKey.Key <> ConsoleKey.Enter
            If nextKey.Key = ConsoleKey.BackSpace Then
                If password.Length > 0 Then
                    password.RemoveAt(password.Length - 1)

                    ' erase the last * as well
                    Console.Write(nextKey.KeyChar)
                    Console.Write(" ")
                    Console.Write(nextKey.KeyChar)
                End If
            Else
                password.AppendChar(nextKey.KeyChar)
                Console.Write("*")
            End If

            nextKey = Console.ReadKey(True)
        End While

        Console.WriteLine()

        ' lock the password down
        password.MakeReadOnly()
        Return password

    End Function
End Module

설명

ZeroFreeCoTaskMemAnsi메서드는 먼저 0을 해제 한 다음 메서드를 사용 하 여 할당 된 관리 되지 않는 메모리를 해제 SecureStringToCoTaskMemAnsi 합니다.The ZeroFreeCoTaskMemAnsi method first zeros out and then frees unmanaged memory that was allocated using the SecureStringToCoTaskMemAnsi method.

적용 대상