WIN API访问数据库

在VC中新建一个Win32 Application工程，并在同一目录下面新建一个book.mdb的数据库，其中有一个表BookInfo,表中有以下几项：

id;

BookName;

Author;

Press;

Price;

Published；

1。先File->Open,打开一个数据库文件，选择book.mdb；

2。再Data->Connect，连接数据库；

3。Data->Query，查询数据中BookName项。

//------------------------------------------------------------------------------//Copyright (c) 2009 eryar All rights reserved.////File:Main.cpp//Author:[e-mail]//Date:2009-11-8 16:09//Version:1.0v////Description:ODBC编写程序访问数据库的操作示例。////==============================================================================#include <windows.h>#include <sqlext.h>#include <odbcinst.h>#defineIDM_FILE_OPEN100001#define IDM_FILE_EXIT100002#define IDM_HELP_CONTENT200001#define IDM_HELP_ABOUT200002#define IDM_DATA_CONNECT300001#define IDM_DATA_QUERY300002char*szAppName = "ODBC Demo";HINSTANCEghInst;HMENUWinMainMenu(HWND);LRESULT CALLBACKWndProc(HWND, UINT, WPARAM, LPARAM);int WINAPI WinMain(HINSTANCEhInstance, HINSTANCEhPrevInstance, LPSTRlpCmdLine, intnShowCmd) {HWNDhWnd;MSGMsg;WNDCLASSwndclass;char*szClassName = "CODBC";ghInst=hInstance;wndclass.style=CS_HREDRAW|CS_VREDRAW;wndclass.cbClsExtra=0;wndclass.cbWndExtra=0;wndclass.lpfnWndProc=WndProc;wndclass.hInstance=hInstance;wndclass.hIcon=LoadIcon(NULL, IDI_APPLICATION);wndclass.hCursor=LoadCursor(NULL, IDC_ARROW);wndclass.hbrBackground=(HBRUSH)GetStockObject(BLACK_BRUSH);wndclass.lpszMenuName=NULL;wndclass.lpszClassName=szClassName;if (!RegisterClass(&wndclass)) {MessageBox(NULL, "This program requires Windows NT! ", szAppName, MB_OK|MB_ICONERROR);return 0;}hWnd=CreateWindow(szClassName,szAppName,WS_OVERLAPPEDWINDOW,CW_USEDEFAULT, CW_USEDEFAULT,CW_USEDEFAULT, CW_USEDEFAULT,NULL,NULL,hInstance,NULL);ShowWindow(hWnd, nShowCmd);UpdateWindow(hWnd);while (GetMessage(&Msg, NULL, 0, 0)) {TranslateMessage(&Msg);DispatchMessage(&Msg);}return Msg.wParam;}LRESULT CALLBACKWndProc(HWND hWnd, UINT Msg, WPARAM wParam, LPARAM lParam) {HDChDC;PAINTSTRUCTps;SQLRETURNretcode;SQLHENVhenv;staticSQLHDBChdbc;SQLHSTMThstmt;SQLINTEGERcbLength=0;intiBookId=0;charBookTitle[30];switch(Msg) {caseWM_CREATE:WinMainMenu(hWnd);return 0;caseWM_SIZE:return 0;caseWM_PAINT:hDC=BeginPaint(hWnd, &ps);EndPaint(hWnd, &ps);return 0;caseWM_COMMAND:switch(wParam) {caseIDM_FILE_OPEN:retcode=SQLConfigDataSource(hWnd, ODBC_ADD_SYS_DSN, "Microsoft Access Driver (*.mdb)", "" );if (!retcode) {MessageBox(hWnd, "系统数据源配置错误！ ", szAppName, MB_OK|MB_ICONERROR);}else {MessageBox(hWnd, "数据库配置成功！", szAppName, MB_OK|MB_ICONINFORMATION);}return 0;caseIDM_FILE_EXIT:PostQuitMessage(0);return 0;caseIDM_DATA_CONNECT:retcode=SQLAllocHandle(SQL_HANDLE_ENV, SQL_NULL_HANDLE, &henv);if (retcode == SQL_SUCCESS) {retcode=SQLSetEnvAttr(henv, SQL_ATTR_ODBC_VERSION, (void*)SQL_OV_ODBC3, 0);if (retcode == SQL_SUCCESS) {retcode=SQLAllocHandle(SQL_HANDLE_DBC, henv, &hdbc);if (retcode == SQL_SUCCESS) {retcode = SQLConnect(hdbc, (SQLCHAR*)"book", SQL_NTS, (SQLCHAR*)"admin", SQL_NTS, (SQLCHAR*)" ", SQL_NTS);if (retcode == SQL_SUCCESS) {MessageBox(hWnd, "数据库连接成功！", szAppName, MB_OK|MB_ICONINFORMATION);} else {MessageBox(hWnd, "SQLConnect : 数据库连接失败！ ", szAppName, MB_OK|MB_ICONERROR);SQLFreeHandle(SQL_HANDLE_DBC, hdbc);SQLFreeHandle(SQL_HANDLE_ENV, henv);}}else {MessageBox(hWnd, "SQLAllocHandle : SQL_HANDLE_DBC 连接句柄分配错误！ ", szAppName, MB_OK|MB_ICONERROR);SQLFreeHandle(SQL_HANDLE_DBC, hdbc);SQLFreeHandle(SQL_HANDLE_ENV, henv);}} else {MessageBox(hWnd, "SQLSetEnvAttr : 属性设置错误！ ", szAppName, MB_OK|MB_ICONERROR);SQLFreeHandle(SQL_HANDLE_ENV, henv);}}else {MessageBox(hWnd, "SQLAllocHandle : SQL_HANDLE_ENV 环境变量分配错误！ ", szAppName, MB_OK|MB_ICONERROR);SQLFreeHandle(SQL_HANDLE_ENV, henv);}return 0;caseIDM_DATA_QUERY://charbuffer[30];retcode=SQLAllocHandle(SQL_HANDLE_STMT, hdbc, &hstmt);if (retcode == SQL_SUCCESS) {SQLBindCol(hstmt, 1, SQL_C_CHAR, (SQLPOINTER)&BookTitle , sizeof(BookTitle), &cbLength );retcode=SQLExecDirect(hstmt, (SQLCHAR*)"select BookName from BookInfo ", SQL_NTS);if (retcode == SQL_SUCCESS) {while( SQLFetch(hstmt) == SQL_SUCCESS) {MessageBox(hWnd, BookTitle, szAppName, MB_OK);} } else {MessageBox(hWnd, "SQLExecDirect : 数据库操作错误！ ", szAppName, MB_OK|MB_ICONERROR);SQLFreeHandle(SQL_HANDLE_STMT, hstmt);}}else {MessageBox(hWnd, "SQLAllocHandle : SQL_HANDLE_STMT 语句变量分配错误！ ", szAppName, MB_OK|MB_ICONERROR);SQLFreeHandle(SQL_HANDLE_STMT, hstmt);}return 0;caseIDM_HELP_CONTENT:MessageBox(hWnd, "help content ", szAppName, MB_OK);return 0;caseIDM_HELP_ABOUT:MessageBox(hWnd, "help about ", szAppName, MB_OK);return 0;}return 0;caseWM_SYSCOMMAND:switch(wParam) {caseSC_CLOSE:if (MessageBox(hWnd, "Are you sure to quit? ", szAppName, MB_YESNOCANCEL|MB_ICONQUESTION) == IDYES) {PostQuitMessage(0);}return 0;default:return DefWindowProc(hWnd, Msg, wParam, lParam);}return 0;caseWM_KEYDOWN:switch(wParam) {caseVK_ESCAPE:PostQuitMessage(0);}return 0;caseWM_DESTROY:PostQuitMessage(0);return 0;}return DefWindowProc(hWnd, Msg, wParam, lParam);} // WndProc/**/HMENUWinMainMenu(HWND hWnd) {HMENUhMenu;HMENUhMenuPopup;hMenu=CreateMenu();// FilehMenuPopup=CreatePopupMenu();AppendMenu(hMenuPopup, MF_STRING, IDM_FILE_OPEN, "&Open");AppendMenu(hMenuPopup, MF_STRING, IDM_FILE_EXIT, "&Exit");AppendMenu(hMenu, MF_POPUP, (UINT)hMenuPopup, "&File");// DatahMenuPopup=CreatePopupMenu();AppendMenu(hMenuPopup, MF_STRING, IDM_DATA_CONNECT, "&Connect");AppendMenu(hMenuPopup, MF_STRING, IDM_DATA_QUERY, "&Query");AppendMenu(hMenu, MF_POPUP, (UINT)hMenuPopup, "&Data");// HelphMenuPopup=CreatePopupMenu();AppendMenu(hMenuPopup, MF_STRING, IDM_HELP_CONTENT, "&Content");AppendMenu(hMenuPopup, MF_STRING, IDM_HELP_ABOUT , "&About");AppendMenu(hMenu, MF_POPUP, (UINT)hMenuPopup, "&Help");SetMenu(hWnd, hMenu);return hMenu;} // WinMainMenu