Marshal.SecureStringToCoTaskMemAnsi(SecureString) 方法

定义

重要

此 API 不符合 CLS。

将托管 SecureString 对象的内容复制到从非托管 COM 任务分配器分配的内存块。Copies the contents of a managed SecureString object to a block of memory allocated from the unmanaged COM task allocator.

public:
 static IntPtr SecureStringToCoTaskMemAnsi(System::Security::SecureString ^ s);
public static IntPtr SecureStringToCoTaskMemAnsi (System.Security.SecureString s);
[System.CLSCompliant(false)]
public static IntPtr SecureStringToCoTaskMemAnsi (System.Security.SecureString s);
[System.Security.SecurityCritical]
public static IntPtr SecureStringToCoTaskMemAnsi (System.Security.SecureString s);
static member SecureStringToCoTaskMemAnsi : System.Security.SecureString -> nativeint
[<System.CLSCompliant(false)>]
static member SecureStringToCoTaskMemAnsi : System.Security.SecureString -> nativeint
[<System.Security.SecurityCritical>]
static member SecureStringToCoTaskMemAnsi : System.Security.SecureString -> nativeint
Public Shared Function SecureStringToCoTaskMemAnsi (s As SecureString) As IntPtr

参数

s
SecureString

要复制的托管对象。The managed object to copy.

返回

IntPtr

非托管内存中将 s 参数复制到的地址;如果提供了 null 对象,则为 0。The address, in unmanaged memory, where the s parameter was copied to, or 0 if a null object was supplied.

属性

例外

s 参数为 nullThe s parameter is null.

没有足够的可用内存。There is insufficient memory available.

示例

下面的示例使用 SecureStringToCoTaskMemAnsi 方法将对象的内容封送和解密 SecureString 到非托管内存块。The following example uses the SecureStringToCoTaskMemAnsi method to marshal and decrypt the contents of a SecureString object to a block of unmanaged memory. 然后,它使用 ZeroFreeCoTaskMemAnsi 方法零出并释放非托管块。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

注解

SecureStringToCoTaskMemAnsi 方法对于自定义封送或混合托管和非托管代码很有用。The SecureStringToCoTaskMemAnsi method is useful for custom marshaling or when mixing managed and unmanaged code. 由于此方法会分配字符串所需的非托管内存,因此请始终通过调用来释放内存 ZeroFreeCoTaskMemAnsiBecause this method allocates the unmanaged memory required for a string, always free the memory by calling ZeroFreeCoTaskMemAnsi. 将字符串的字符复制为 ANSI 字符。The characters of the string are copied as ANSI characters.

适用于