假设用户的登陆方式为网络登陆，那么我们可以安以下的步骤，来实现保存密码和防止ESC键:

1.在RunService处(HKLM\)填上一个服务程序，可保证在登陆框出现前启动。

2.在Service的程序中用FindWindow,FindWindowEx找到窗口和Edit，Button的Handle,便可控制。

代码如下：

#include "stdafx.h"
#include <stdio.h>
#include <windows.h>
#include <winuser.h>
#include <process.h>
#include "UsbEkey.h"

//-----------------------------------------------------------------------
//       G L O B A L S
//-----------------------------------------------------------------------
const LPCSTR DLGTTLE = "请输入网络密码";
const LPCSTR CHKTTLE = "保存密码";
const LPSTR CHK_APP_NAME = "ChkBox.exe";

const UINT RSP_SIMPLE_SERVICE = 1;
const UINT RSP_UNREGISTER_SERVICE = 0;

typedef DWORD (WINAPI * pRegFunction)(
           DWORD dwProcessId, 
           DWORD dwType);

HWND hDlg = NULL;
HWND hUserName = NULL;
HWND hPwd = NULL;
HWND hDomain = NULL;
HWND hBtnOk = NULL;
HWND hBtnCancel = NULL;
HWND hChkBox = NULL;
STARTUPINFO si;
PROCESS_INFORMATION pi;
ACCOUNT g_Account,g_NewAccount;

//-----------------------------------------------------------------------
// Find The Application CreateCheckBox Contrl's
//-----------------------------------------------------------------------
HWND GetMyChkBox(HWND hDlg)
{
 HWND hTmp = NULL,hChk = NULL;
 bool b1 = false,b2 = false;
 
 hTmp =FindWindowEx(hDlg,NULL,"button",NULL);
 hChk = hTmp;
 while (!b1 && !b2)
 {  
  hChk = GetNextDlgGroupItem(hDlg,hChk,FALSE);
  
  char buf[255];
  GetWindowText(hChk,buf,255);
  if (strcmp(buf,CHKTTLE) == 0 )
  {
   b1 = true;  
  }
  if (hTmp == hChk)
  {
   b2 = true; 
   OutputDebugString("Not Find The CheckBox\n");
  }  
 }

 return hChk;
}
//-----------------------------------------------------------------------
// Get The UserName/Pwd/Domain And Save To The UsbEkey Thread
//-----------------------------------------------------------------------
void GetTextFunProc(PVOID parg)
{
 while (NULL != hDlg )
 { 
  SendMessage(hUserName,WM_GETTEXT,255,(LPARAM)g_NewAccount.UserName);
  SendMessage(hPwd,WM_GETTEXT,255,(LPARAM)g_NewAccount.PassWord);
  SendMessage(hDomain,WM_GETTEXT,255,(LPARAM)g_NewAccount.Domain);  
  
  hChkBox = GetMyChkBox(hDlg);
  if (NULL == hChkBox) {
   break;
  }
  int iRet = SendMessage(hChkBox,BM_GETCHECK ,0,0);
  if (BST_CHECKED == iRet){
   g_NewAccount.Flag = FLAG_SAVE_PWD;  
  }
  
  if (BST_UNCHECKED == iRet){
   g_NewAccount.Flag = FLAG_NOT_SAVE_PWD;
  }  
  
  char buf[255];
  sprintf(buf,"GetText:\t UserName=%s;Pwd=%s;Domain=%s\;Flag=%d\n",
   g_NewAccount.UserName,g_NewAccount.PassWord,g_NewAccount.Domain,
   g_NewAccount.Flag);
  OutputDebugString(buf);

  hDlg = FindWindow(NULL,DLGTTLE);
  
  Sleep(100);  
 }
 
 //
 // On There Save UserName/Pwd/Domain to UsbEkey
 //
 if (g_NewAccount.Flag != g_Account.Flag
  || g_NewAccount.Flag == FLAG_SAVE_PWD)
 {
  if (0 == WriteAccount(g_NewAccount))
  {
   memcpy(&g_Account,&g_NewAccount,sizeof(ACCOUNT));
  }
  
 } 
 
 //
 // Close CreaeChkBox Application
 // 
 TerminateProcess(pi.hProcess,0); 
    CloseHandle( pi.hProcess );
    CloseHandle( pi.hThread );
 return;
}

//-----------------------------------------------------------------------
// Set The UserName/Pwd/Domain Thread
//-----------------------------------------------------------------------
void SetTextFunProc(PVOID parg)
{ 
 //DWORD dwStartTime;

 //dwStartTime = GetTickCount();
 
 while (true)
 {
  if (strlen(g_Account.PassWord) <= 0
   && strlen(g_Account.UserName) <= 0
   && strlen(g_Account.Domain) <= 0)
  {
   OutputDebugString("ReadAccount Start....\n"); 
   ReadAccount(g_Account);   
  }  
  

  hDlg = FindWindow(NULL,DLGTTLE);
  if (NULL != hDlg)
  {
   OutputDebugString("Find The Login Dlg\n");

   hUserName = FindWindowEx(hDlg,NULL,"edit",NULL);
   if (hUserName == NULL)
   {
    OutputDebugString("Can Not Find The Edit_UserName\n");
    return;
   }

   hPwd = GetNextDlgTabItem(hDlg,hUserName,FALSE);
   if (hPwd == NULL)
   {
    OutputDebugString("Can Not Find The Edit_PassWord\n");
    return;
   }

   hDomain = GetNextDlgTabItem(hDlg,hPwd,FALSE);
   if (hDomain == NULL)
   {
    OutputDebugString("Can Not Find The Edit_Domain\n");
    return;
   }   

   hBtnOk = GetNextDlgTabItem(hDlg,hDomain,FALSE);
   if (hDomain == NULL)
   {
    OutputDebugString("Can Not Find The Btn_OK\n");
    return;
   }   

   hBtnCancel = GetNextDlgTabItem(hDlg,hBtnOk,FALSE);
   if (hDomain == NULL)
   {
    OutputDebugString("Can Not Find The Btn_Cancel\n");
    return;
   } 
   
   //
   // Exec CreateChkBox Application
   //    
   OutputDebugString("CreateProcess CreateCheckBox\n");
   CreateProcess(NULL,CHK_APP_NAME,NULL,            
     NULL, FALSE,0,NULL,NULL,&si,&pi );   

   Sleep(500);
   hChkBox = GetMyChkBox(hDlg);
   if (g_Account.Flag == FLAG_SAVE_PWD){  
    SendMessage(hChkBox,BM_SETCHECK ,(WPARAM)BST_CHECKED,0);
   }

   //
   // Set Pwd/UserName/Domain
   // 
   if (g_Account.Flag == FLAG_SAVE_PWD) { 
    if (strlen(g_Account.UserName) > 0) {
     SendMessage(hUserName,WM_SETTEXT,255,(LPARAM)g_Account.UserName);
    }
    
    if (strlen(g_Account.PassWord) > 0) {
     SendMessage(hPwd,WM_SETTEXT,255,(LPARAM)g_Account.PassWord);
    }
    
    if (strlen(g_Account.Domain) > 0) {
     SendMessage(hDomain,WM_SETTEXT,255,(LPARAM)g_Account.Domain);
    }
    
    //
    //  Disable The "ESC" and "Cancel" Buttton
    //                 
    char szBuf[255];
    GetWindowText(hBtnCancel,szBuf,255);
    if (strcmp("取消",szBuf) == 0)
    {
     EnableWindow(hBtnCancel,FALSE);
    }    
    //keybd_event( VK_RETURN,0x45,KEYEVENTF_EXTENDEDKEY | 0,0 );    
   }   

   GetTextFunProc(NULL);
   OutputDebugString("Create The GetTextFunProc Thread!\n");
  }
  
  Sleep(1000*3);
  
  //
  // After Half Hour Application Exit
  //  
  //if ((GetTickCount() - dwStartTime)/(1000*60) >=30) {
  // break;
  //}
  OutputDebugString("SetText Thread Is Runing...\n");
 }
 
 return ;
}

//-----------------------------------------------------------------------
// InitlizeFuntions
//-----------------------------------------------------------------------
bool Initlize()
{
 //bool pOld;
 //SystemParametersInfo(SPI_SETSCREENSAVERRUNNING,true,&pOld,SPIF_UPDATEINIFILE);
 
 //
 //  RegisterServiceProcess then TaskMgr Can't Find It
 // 
 HINSTANCE hKernelLib;
 pRegFunction RegisterServiceProcess; 
 
 hKernelLib = LoadLibrary("kernel32.dll");
 if(hKernelLib)
 {
  RegisterServiceProcess =
   (pRegFunction)GetProcAddress(hKernelLib,"RegisterServiceProcess");
  if(RegisterServiceProcess){
    RegisterServiceProcess(GetCurrentProcessId(),RSP_SIMPLE_SERVICE);
  }
  
 }
 
 memset(&g_Account,0,sizeof(ACCOUNT));
 memset(&g_NewAccount,0,sizeof(ACCOUNT));
 ZeroMemory( &si, sizeof(si) );
    si.cb = sizeof(si);
    ZeroMemory( &pi, sizeof(pi) );

 return true;
}

//-----------------------------------------------------------------------
// UnInitlizeFuntions
//-----------------------------------------------------------------------
bool UnInitlize()
{
 DestoryEKey();
// FreeEKeyFuns();
 return true;
}
//------------------------------------------------------------------------
//  WinMain Entry
//-----------------------------------------------------------------------
int APIENTRY WinMain(HINSTANCE hInstance,
                     HINSTANCE hPrevInstance,
                     LPSTR     lpCmdLine,
                     int       nCmdShow)
{
 HANDLE hThead;
 Initlize(); 
 
 hThead = (HANDLE)_beginthread(SetTextFunProc,NULL,NULL);
 OutputDebugString("Create The SetTextFunProc Thread!\n");
 
 WaitForSingleObject(hThead,INFINITE);
 CloseHandle(hThead);

 OutputDebugString("Application End!\n"); 
 UnInitlize();

 return 0;
}

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