Marshal.ZeroFreeGlobalAllocAnsi(IntPtr) 메서드

정의

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

public:
 static void ZeroFreeGlobalAllocAnsi(IntPtr s);
[System.Security.SecurityCritical]
public static void ZeroFreeGlobalAllocAnsi (IntPtr s);
public static void ZeroFreeGlobalAllocAnsi (IntPtr s);
[<System.Security.SecurityCritical>]
static member ZeroFreeGlobalAllocAnsi : nativeint -> unit
static member ZeroFreeGlobalAllocAnsi : nativeint -> unit
Public Shared Sub ZeroFreeGlobalAllocAnsi (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 SecureStringToGlobalAllocAnsi 개체의 내용을 SecureString 관리 되지 않는 메모리 블록으로 마샬링하고 해독 합니다.The following example uses the SecureStringToGlobalAllocAnsi method to marshal and decrypt the contents of a SecureString object to a block of unmanaged memory. 그런 다음 메서드를 사용 하 여 ZeroFreeGlobalAllocAnsi 관리 되지 않는 블록을 삭제 하 고 삭제 합니다.It then uses the ZeroFreeGlobalAllocAnsi method to zero out and dispose the unmanaged block.

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

class Example
{
    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.SecureStringToGlobalAllocAnsi(passWord);
        passWord.Dispose();

        if (unmanagedRef != IntPtr.Zero) {
            Console.WriteLine("Zeroing out unmanaged memory...");
            Marshal.ZeroFreeGlobalAllocAnsi(unmanagedRef);
        }
        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;
    }
}
// The example displays output like the following:
//       Please enter your password: ********
//       Copying and decrypting the string to unmanaged memory...
//       Zeroing out unmanaged memory...
//       Done.
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.SecureStringToGlobalAllocAnsi(passWord)
        passWord.Dispose()

        If unmanagedRef <> IntPtr.Zero Then
            Console.WriteLine("Zeroing out unmanaged memory...")
            Marshal.ZeroFreeGlobalAllocAnsi(unmanagedRef)
        End If
        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
' The example displays output like the following:
'       Please enter your password: ********
'       Copying and decrypting the string to unmanaged memory...
'       Zeroing out unmanaged memory...
'       Done.

설명

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

적용 대상