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将数据从托管对象封送到非托管内存块的问题,请各位高手赐教啊!

用c#做的改建程序,下面是回调函数的代码片段,如果我想把q键改成z键,那么现在问题就来了:
因为KeyBoardHookProc()  CallNextHookEx() 函数的 lParam参数都是指针类型,
我用KeyBoardHookStruct kbh = (KeyBoardHookStruct)Marshal.PtrToStructure(lParam, typeof(KeyBoardHookStruct))这句把非托管的内存的转换成了托管的结构,但是我想用这句Marshal.StructureToPtr(kbh, lParam, false)把值改变后的结构从托管对象转到非托管内存块,但是运行后没起作用。
请各位高手赐教,这里该怎么实现啊?

public static int KeyBoardHookProc(int nCode, int wParam, IntPtr lParam) 
        {
            if (nCode >= 0)
            {
                
                KeyBoardHookStruct kbh = (KeyBoardHookStruct)Marshal.PtrToStructure(lParam, typeof(KeyBoardHookStruct));
                if (kbh.vkCode == (int)Keys.Q)
                {
                    //kbh.vkCode = (int)Keys.Z;
                    //Marshal.StructureToPtr(kbh, lParam, true);
                    //CallNextHookEx(hHook, nCode, wParam, lParam); 
                    return 1;
                }
            }
            return CallNextHookEx(hHook, nCode, wParam, lParam); 

        } 

public class KeyBoardHookStruct 
        { 
            public int vkCode; 
            public int scanCode; 
            public int flags; 
            public int time; 
            public int dwExtraInfo; 
        } 

--------------------编程问答-------------------- 什么叫没起作用,运行结果是什么,断点跟踪的结果呢? --------------------编程问答-------------------- 貌似看不出什么不对的地方~~~~ --------------------编程问答-------------------- 兄台,谢谢你的关注!
下面是全部的代码,你加个窗体,把 button1_Click , button2_Click注册到按钮的事件中,帮我看一下吧。
问题的地方我用红色标明了。
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices;
using System.Reflection;
using System.Diagnostics;
using System.IO; 

namespace HookExample2
{
    public partial class Form1 : Form
    {
        //委托  
    public delegate int HookProc(int nCode, int wParam, IntPtr lParam); 
        static int hHook = 0; 
        public const int WH_KEYBOARD_LL = 13; 
        //LowLevel键盘截获,如果是WH_KEYBOARD=2,并不能对系统键盘截取,Acrobat Reader会在你截取之前获得键盘。  
        HookProc KeyBoardHookProcedure; 
        //键盘Hook结构函数  
        [StructLayout(LayoutKind.Sequential)] 
        public class KeyBoardHookStruct 
        { 
            public int vkCode; 
            public int scanCode; 
            public int flags; 
            public int time; 
            public int dwExtraInfo; 
        } 
        #region DllImport 
        //设置钩子  
        [DllImport("user32.dll")] 
        public static extern int SetWindowsHookEx(int idHook, HookProc lpfn, IntPtr hInstance, int threadId); 
        [DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)] 
        //抽掉钩子  
        public static extern bool UnhookWindowsHookEx(int idHook); 
        [DllImport("user32.dll")] 
        //调用下一个钩子  
        public static extern int CallNextHookEx(int idHook, int nCode, int wParam, IntPtr lParam); 

        [DllImport("kernel32.dll")] 
        public static extern int GetCurrentThreadId(); 

        [DllImport("kernel32.dll")] 
        public static extern IntPtr GetModuleHandle(string name); 

        #endregion 
        #region 自定义事件 
        public void Hook_Start() 
        { 
            // 安装键盘钩子  
            if (hHook == 0) 
            { 
                KeyBoardHookProcedure = new HookProc(KeyBoardHookProc); 

                //hHook = SetWindowsHookEx(2,  
                //            KeyBoardHookProcedure,  
                //          GetModuleHandle(Process.GetCurrentProcess().MainModule.ModuleName), GetCurrentThreadId());  

                hHook = SetWindowsHookEx(WH_KEYBOARD_LL, 
                          KeyBoardHookProcedure, 
                        GetModuleHandle(Process.GetCurrentProcess().MainModule.ModuleName), 0); 

                //如果设置钩子失败.  
                if (hHook == 0) 
                { 
                    Hook_Clear(); 
                    //throw new Exception("设置Hook失败!");  
                } 
            } 
        } 

        //取消钩子事件  
        public void Hook_Clear() 
        { 
            bool retKeyboard = true; 
            if (hHook != 0) 
            { 
                retKeyboard = UnhookWindowsHookEx(hHook); 
                hHook = 0; 
            } 
            //如果去掉钩子失败.  
            if (!retKeyboard) throw new Exception("UnhookWindowsHookEx failed."); 
        } 

        //这里可以添加自己想要的信息处理  
        public static int KeyBoardHookProc(int nCode, int wParam, IntPtr lParam) 
        {
            if (nCode >= 0)
            {
                
                KeyBoardHookStruct kbh = (KeyBoardHookStruct)Marshal.PtrToStructure(lParam, typeof(KeyBoardHookStruct));
                if (kbh.vkCode == (int)Keys.Q)
                {
                    kbh.vkCode = (int)Keys.Z;
                    Marshal.StructureToPtr(kbh, lParam, true);
                    return CallNextHookEx(hHook, nCode, wParam, lParam); 
                    //return 1;
                }
            }            return CallNextHookEx(hHook, nCode, wParam, lParam); 

        } 
        #endregion 

        public Form1() 
        { 

            InitializeComponent(); 
        } 
        private void button1_Click(object sender, EventArgs e) 
        { 
            Hook_Start(); 
        } 

        private void button2_Click(object sender, EventArgs e) 
        { 
            Hook_Clear(); 
        } 

    }
} --------------------编程问答-------------------- 兄台,谢谢你的关注! 
下面是全部的代码,你加个窗体,把 button1_Click , button2_Click注册到按钮的事件中,帮我看一下吧。 
问题的地方我用红色标明了。 
using System; 
using System.Collections.Generic; 
using System.ComponentModel; 
using System.Data; 
using System.Drawing; 
using System.Text; 
using System.Windows.Forms; 
using System.Runtime.InteropServices; 
using System.Reflection; 
using System.Diagnostics; 
using System.IO; 

namespace HookExample2 

    public partial class Form1 : Form 
    { 
        //委托  
    public delegate int HookProc(int nCode, int wParam, IntPtr lParam); 
        static int hHook = 0; 
        public const int WH_KEYBOARD_LL = 13; 
        //LowLevel键盘截获,如果是WH_KEYBOARD=2,并不能对系统键盘截取,Acrobat Reader会在你截取之前获得键盘。  
        HookProc KeyBoardHookProcedure; 
        //键盘Hook结构函数  
        [StructLayout(LayoutKind.Sequential)] 
        public class KeyBoardHookStruct 
        { 
            public int vkCode; 
            public int scanCode; 
            public int flags; 
            public int time; 
            public int dwExtraInfo; 
        } 
        #region DllImport 
        //设置钩子  
        [DllImport("user32.dll")] 
        public static extern int SetWindowsHookEx(int idHook, HookProc lpfn, IntPtr hInstance, int threadId); 
        [DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)] 
        //抽掉钩子  
        public static extern bool UnhookWindowsHookEx(int idHook); 
        [DllImport("user32.dll")] 
        //调用下一个钩子  
        public static extern int CallNextHookEx(int idHook, int nCode, int wParam, IntPtr lParam); 

        [DllImport("kernel32.dll")] 
        public static extern int GetCurrentThreadId(); 

        [DllImport("kernel32.dll")] 
        public static extern IntPtr GetModuleHandle(string name); 

        #endregion 
        #region 自定义事件 
        public void Hook_Start() 
        { 
            // 安装键盘钩子  
            if (hHook == 0) 
            { 
                KeyBoardHookProcedure = new HookProc(KeyBoardHookProc); 

                //hHook = SetWindowsHookEx(2,  
                //            KeyBoardHookProcedure,  
                //          GetModuleHandle(Process.GetCurrentProcess().MainModule.ModuleName), GetCurrentThreadId());  

                hHook = SetWindowsHookEx(WH_KEYBOARD_LL, 
                          KeyBoardHookProcedure, 
                        GetModuleHandle(Process.GetCurrentProcess().MainModule.ModuleName), 0); 

                //如果设置钩子失败.  
                if (hHook == 0) 
                { 
                    Hook_Clear(); 
                    //throw new Exception("设置Hook失败!");  
                } 
            } 
        } 

        //取消钩子事件  
        public void Hook_Clear() 
        { 
            bool retKeyboard = true; 
            if (hHook != 0) 
            { 
                retKeyboard = UnhookWindowsHookEx(hHook); 
                hHook = 0; 
            } 
            //如果去掉钩子失败.  
            if (!retKeyboard) throw new Exception("UnhookWindowsHookEx failed."); 
        } 

        //这里可以添加自己想要的信息处理  
        public static int KeyBoardHookProc(int nCode, int wParam, IntPtr lParam) 
        { 
          if (nCode >= 0) 
            { 
                
                KeyBoardHookStruct kbh = (KeyBoardHookStruct)Marshal.PtrToStructure(lParam, typeof(KeyBoardHookStruct)); 
                if (kbh.vkCode == (int)Keys.Q) 
                { 
                    kbh.vkCode = (int)Keys.Z; 
                    Marshal.StructureToPtr(kbh, lParam, true); 
                    return CallNextHookEx(hHook, nCode, wParam, lParam); 
                    //return 1; 
                } 
            }            return CallNextHookEx(hHook, nCode, wParam, lParam);         } 
        #endregion 

        public Form1() 
        { 

            InitializeComponent(); 
        } 
        private void button1_Click(object sender, EventArgs e) 
        { 
            Hook_Start(); 
        } 

        private void button2_Click(object sender, EventArgs e) 
        { 
            Hook_Clear(); 
        } 

    } 
} --------------------编程问答-------------------- 已经解决了,不麻烦大家了
--------------------编程问答-------------------- OK --------------------编程问答-------------------- --------------------编程问答-------------------- 怎么解决的呀?我跟你碰到一样的问题 希望 楼主解答下
补充:.NET技术 ,  C#
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