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/ Windows 95 API Bible / Windows 95 API Bible 3 Disc Set.iso / Win32 API Bible Book 3 of 3 / CHAPTER7 / DESCRCOL.C < prev    next >
C/C++ Source or Header  |  1996-04-28  |  12KB  |  347 lines
  1.  
  2. #include <windows.h>  
  3. #include <stdio.h>
  4. #include "descrcol.h"
  5. #include "sqlext.h"  
  6.  
  7.  
  8. #if defined (WIN32)
  9.     #define IS_WIN32 TRUE
  10. #else
  11.     #define IS_WIN32 FALSE
  12. #endif
  13.  
  14. #define IS_NT      IS_WIN32 && (BOOL)(GetVersion() < 0x80000000)
  15. #define IS_WIN32S  IS_WIN32 && (BOOL)(!(IS_NT) && (LOBYTE(LOWORD(GetVersion()))<4))
  16. #define IS_WIN95   (BOOL)(!(IS_NT) && !(IS_WIN32S)) && IS_WIN32
  17.  
  18. HINSTANCE hInst;   // current instance
  19.  
  20. LPCTSTR lpszAppName = "MyApp";
  21. LPCTSTR lpszTitle   = "SQLDescribeCol()"; 
  22.  
  23.  
  24. BOOL RegisterWin95( CONST WNDCLASS* lpwc );
  25. VOID BuildOutputStr( LPSTR pszLBStr, LPCSTR lpszColName, 
  26.                                      SWORD  fSqlType, UDWORD cbColDef, 
  27.                                      SWORD  ibScale,  SWORD  fNullable );
  28.  
  29.  
  30. int APIENTRY WinMain( HINSTANCE hInstance, HINSTANCE hPrevInstance,
  31.                       LPTSTR lpCmdLine, int nCmdShow)
  32. {
  33.    MSG      msg;
  34.    HWND     hWnd; 
  35.    WNDCLASS wc;
  36.  
  37.    wc.style         = CS_HREDRAW | CS_VREDRAW;
  38.    wc.lpfnWndProc   = (WNDPROC)WndProc;       
  39.    wc.cbClsExtra    = 0;                      
  40.    wc.cbWndExtra    = 0;                      
  41.    wc.hInstance     = hInstance;              
  42.    wc.hIcon         = LoadIcon (hInstance, lpszAppName); 
  43.    wc.hCursor       = LoadCursor(NULL, IDC_ARROW);
  44.    wc.hbrBackground = (HBRUSH)(COLOR_WINDOW+1);
  45.    wc.lpszMenuName  = lpszAppName;              
  46.    wc.lpszClassName = lpszAppName;              
  47.  
  48.    if ( IS_WIN95 )
  49.    {
  50.       if ( !RegisterWin95( &wc ) )
  51.          return( FALSE );
  52.    }
  53.    else if ( !RegisterClass( &wc ) )
  54.       return( FALSE );
  55.  
  56.    hInst = hInstance; 
  57.  
  58.    hWnd = CreateWindow( lpszAppName, 
  59.                         lpszTitle,    
  60.                         WS_OVERLAPPEDWINDOW, 
  61.                         CW_USEDEFAULT, 0, 
  62.                         CW_USEDEFAULT, 0,  
  63.                         NULL,              
  64.                         NULL,              
  65.                         hInstance,         
  66.                         NULL               
  67.                       );
  68.  
  69.    if ( !hWnd ) 
  70.       return( FALSE );
  71.  
  72.    ShowWindow( hWnd, nCmdShow ); 
  73.    UpdateWindow( hWnd );         
  74.  
  75.    while( GetMessage( &msg, NULL, 0, 0) )   
  76.    {
  77.       TranslateMessage( &msg ); 
  78.       DispatchMessage( &msg );  
  79.    }
  80.  
  81.    return( msg.wParam ); 
  82. }
  83.  
  84.  
  85. BOOL RegisterWin95( CONST WNDCLASS* lpwc )
  86. {
  87.    WNDCLASSEX wcex;
  88.  
  89.    wcex.style         = lpwc->style;
  90.    wcex.lpfnWndProc   = lpwc->lpfnWndProc;
  91.    wcex.cbClsExtra    = lpwc->cbClsExtra;
  92.    wcex.cbWndExtra    = lpwc->cbWndExtra;
  93.    wcex.hInstance     = lpwc->hInstance;
  94.    wcex.hIcon         = lpwc->hIcon;
  95.    wcex.hCursor       = lpwc->hCursor;
  96.    wcex.hbrBackground = lpwc->hbrBackground;
  97.    wcex.lpszMenuName  = lpwc->lpszMenuName;
  98.    wcex.lpszClassName = lpwc->lpszClassName;
  99.  
  100.    // Added elements for Windows 95.
  101.    //...............................
  102.    wcex.cbSize = sizeof(WNDCLASSEX);
  103.    wcex.hIconSm = LoadImage(wcex.hInstance, lpwc->lpszClassName, 
  104.                             IMAGE_ICON, 16, 16,
  105.                             LR_DEFAULTCOLOR );
  106.             
  107.    return RegisterClassEx( &wcex );
  108. }
  109.  
  110.  
  111. LRESULT CALLBACK WndProc( HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam )
  112. {
  113. static HENV  hEnv  = NULL;
  114. static HDBC  hDBC  = NULL;
  115. static HWND  hList = NULL;
  116.  
  117. static UCHAR szLBStr  [256];
  118. static UCHAR szColName[ 32];
  119.  
  120. UCHAR  szSqlStr[]  = "Select dept_id, dept_name, dept_head_id From department";
  121.  
  122.    switch( uMsg )
  123.    {
  124.       case WM_CREATE :
  125.               {
  126.                  RETCODE retCode;
  127.  
  128.                  // Allocate Environment and Connection.
  129.                  //.....................................
  130.                  SQLAllocEnv( &hEnv );
  131.                  SQLAllocConnect( hEnv, &hDBC );
  132.  
  133.                  // Connect to the data source
  134.                  //...........................
  135.                  retCode = SQLConnect( hDBC, 
  136.                              "Test Data Source", SQL_NTS,
  137.                              "DBA",              SQL_NTS,  
  138.                              "SQL",              SQL_NTS );
  139.  
  140.                  if ( retCode != SQL_SUCCESS )
  141.                  {
  142.                     SQLFreeConnect( hDBC );
  143.                     SQLFreeEnv( hEnv );
  144.                     return( -1 );
  145.                  }
  146.  
  147.                  if ( retCode == SQL_SUCCESS )
  148.                  {
  149.                     int nTabSize = 50;
  150.  
  151.                     hList = CreateWindow( "LISTBOX", "",    
  152.                                LBS_NOTIFY | LBS_USETABSTOPS |
  153.                                LBS_NOINTEGRALHEIGHT  | 
  154.                                WS_BORDER  | WS_CHILD | 
  155.                                WS_VISIBLE | WS_VSCROLL, 
  156.                                0, 0, 0, 0, 
  157.                                hWnd, (HMENU)101,
  158.                                hInst, NULL );
  159.                     
  160.                     SendMessage( hList, LB_SETTABSTOPS, 
  161.                                  1, (LPARAM)&nTabSize );
  162.                  }
  163.               }
  164.               break;
  165.  
  166.       case WM_SIZE :
  167.               MoveWindow( hList, 0, 0, LOWORD( lParam ), 
  168.                                        HIWORD( lParam ), TRUE );
  169.               break; 
  170.               
  171.       case WM_COMMAND :
  172.               switch( LOWORD( wParam ) )
  173.               {
  174.                  case IDM_TEST :
  175.                         {
  176.                            HSTMT   hStmt;
  177.                            RETCODE retCode;
  178.   
  179.                            // Allocate a statement handle for the query.
  180.                            // ..........................................
  181.                            SQLAllocStmt( hDBC, &hStmt );
  182.  
  183.                            // Call SQLPrepare() to execute the query.
  184.                            // ..........................................
  185.                            retCode = SQLPrepare( hStmt, szSqlStr, SQL_NTS );
  186.                            
  187.                            if( retCode == SQL_SUCCESS ||
  188.                                retCode == SQL_SUCCESS_WITH_INFO )
  189.                            {
  190.                               UWORD  iParams = 1;
  191.                               SWORD  nParams;
  192.                               SWORD  cbColName;
  193.                               SWORD  fSqlType;
  194.                               UDWORD cbColDef; 
  195.                               SWORD  ibScale;
  196.                               SWORD  fNullable;
  197.  
  198.                               // Call SQLNumResultCols() to determine the
  199.                               // number of columns in the statement.
  200.                               // ........................................
  201.                               SQLNumResultCols( hStmt, &nParams );
  202.  
  203.                               while( iParams <= nParams )
  204.                               {
  205.                                  // Call SQLDescribeCol() to determine 
  206.                                  // the data type of the columns in the
  207.                                  // prepared query.
  208.                                  // ...................................
  209.  
  210.                                  retCode = SQLDescribeCol( hStmt, iParams, 
  211.                                          szColName, sizeof( szColName ),
  212.                                          &cbColName, &fSqlType, &cbColDef,
  213.                                          &ibScale, &fNullable );
  214.  
  215.                                  if( retCode != SQL_SUCCESS &&
  216.                                      retCode != SQL_SUCCESS_WITH_INFO )
  217.                                     break;
  218.  
  219.                                  BuildOutputStr( szLBStr, szColName, 
  220.                                                           fSqlType, 
  221.                                                           cbColDef, 
  222.                                                           ibScale,  
  223.                                                           fNullable );
  224.  
  225.                                  SendMessage( hList, LB_ADDSTRING, 0, 
  226.                                                     (LPARAM)szLBStr );
  227.  
  228.                                  iParams++;
  229.                               }
  230.                            }
  231.                            
  232.                            // Free the statement handle.
  233.                            // ..........................
  234.                            SQLFreeStmt( hStmt, SQL_DROP );
  235.                         }
  236.                         break;
  237.  
  238.                  case IDM_ABOUT :
  239.                         DialogBox( hInst, "AboutBox", hWnd, (DLGPROC)About );
  240.                         break;
  241.  
  242.                  case IDM_EXIT :
  243.                         DestroyWindow( hWnd );
  244.                         break;
  245.               }
  246.               break;
  247.       
  248.       case WM_DESTROY :
  249.               PostQuitMessage(0);
  250.  
  251.               // Disconnect Environment.
  252.               //........................
  253.               SQLDisconnect( hDBC );
  254.  
  255.               // Free Connection and Environment.
  256.               //.................................
  257.               SQLFreeConnect( hDBC );
  258.               SQLFreeEnv( hEnv );
  259.               break;
  260.  
  261.       default :
  262.             return( DefWindowProc( hWnd, uMsg, wParam, lParam ) );
  263.    }
  264.  
  265.    return( 0L );
  266. }
  267.  
  268. // Builds an output string based on the values 
  269. // returned from the SQLDescribeCol() function.
  270. // ..............................................
  271.  
  272. VOID BuildOutputStr( LPSTR pszLBStr, LPCSTR lpszColName, 
  273.                                      SWORD  fSqlType, UDWORD cbColDef, 
  274.                                      SWORD  ibScale,  SWORD  fNullable )
  275. {
  276.    char szTempStr[32];
  277.  
  278.    pszLBStr[0] = '\0';
  279.  
  280.    strcpy( pszLBStr, lpszColName );
  281.    strcat( pszLBStr, "\t" );
  282.  
  283.    switch( fSqlType )
  284.    {
  285.       case SQL_BIGINT       : strcat( pszLBStr, "BIGINT"        ); break;
  286.       case SQL_BINARY       : strcat( pszLBStr, "BINARY"        ); break;
  287.       case SQL_BIT          : strcat( pszLBStr, "BIT"           ); break;
  288.       case SQL_CHAR         : strcat( pszLBStr, "CHAR"          ); break;
  289.       case SQL_DATE         : strcat( pszLBStr, "DATE"          ); break;
  290.       case SQL_DECIMAL      : strcat( pszLBStr, "DECIMAL"       ); break;
  291.       case SQL_DOUBLE       : strcat( pszLBStr, "DOUBLE"        ); break;
  292.       case SQL_FLOAT        : strcat( pszLBStr, "FLOAT"         ); break;
  293.       case SQL_INTEGER      : strcat( pszLBStr, "INTEGER"       ); break;
  294.       case SQL_LONGVARBINARY: strcat( pszLBStr, "LONGVARBINARY" ); break;
  295.       case SQL_LONGVARCHAR  : strcat( pszLBStr, "LONGVARCHAR"   ); break;
  296.       case SQL_NUMERIC      : strcat( pszLBStr, "NUMERIC"       ); break;
  297.       case SQL_REAL         : strcat( pszLBStr, "REAL"          ); break;
  298.       case SQL_SMALLINT     : strcat( pszLBStr, "SMALLINT"      ); break;
  299.       case SQL_TIME         : strcat( pszLBStr, "TIME"          ); break;
  300.       case SQL_TIMESTAMP    : strcat( pszLBStr, "TIMESTAMP"     ); break;
  301.       case SQL_TINYINT      : strcat( pszLBStr, "TINYINT"       ); break;
  302.       case SQL_VARBINARY    : strcat( pszLBStr, "VARBINARY"     ); break;
  303.       case SQL_VARCHAR      : strcat( pszLBStr, "VARCHAR"       ); break;
  304.       default:   strcat( pszLBStr, "Driver-specific data type." ); break;
  305.    }
  306.    strcat( pszLBStr, "\t" );
  307.  
  308.    itoa( cbColDef, szTempStr, 10 );
  309.    strcat( pszLBStr, szTempStr );
  310.    strcat( pszLBStr, "\t" );
  311.  
  312.    itoa( ibScale, szTempStr, 10 );
  313.    strcat( pszLBStr, szTempStr );
  314.    strcat( pszLBStr, "\t" );
  315.  
  316.    switch( fNullable )
  317.    {
  318.       case SQL_NO_NULLS:         strcat( pszLBStr, "No NULLs." );    break;
  319.       case SQL_NULLABLE:         strcat( pszLBStr, "Nullable." );    break;
  320.       case SQL_NULLABLE_UNKNOWN: strcat( pszLBStr, "NULL unknown." );break;
  321.    }
  322. }
  323.  
  324.  
  325. LRESULT CALLBACK About( HWND hDlg,           
  326.                         UINT message,        
  327.                         WPARAM wParam,       
  328.                         LPARAM lParam)
  329. {
  330.    switch (message) 
  331.    {
  332.        case WM_INITDIALOG: 
  333.                return (TRUE);
  334.  
  335.        case WM_COMMAND:                              
  336.                if (   LOWORD(wParam) == IDOK         
  337.                    || LOWORD(wParam) == IDCANCEL)    
  338.                {
  339.                        EndDialog(hDlg, TRUE);        
  340.                        return (TRUE);
  341.                }
  342.                break;
  343.    }
  344.  
  345.    return (FALSE); 
  346. }
  347.