SELECT.C

/******************************************************************************\ 
*       This is a part of the Microsoft Source Code Samples.  
*       Copyright 1993 - 1998 Microsoft Corporation. 
*       All rights reserved.  
*       This source code is only intended as a supplement to  
*       Microsoft Development Tools and/or WinHelp documentation. 
*       See these sources for detailed information regarding the  
*       Microsoft samples programs. 
\******************************************************************************/ 
 
/**************************************************************************** 
 
    PROGRAM: Select.c 
 
    PURPOSE: Contains library routines for selecting a region 
 
    FUNCTIONS: 
 
        StartSelection(HWND, POINT, LPRECT, int) - begin selection area 
        UpdateSelection(HWND, POINT, LPRECT, int) - update selection area 
        EndSelection(POINT, LPRECT) - end selection area 
        ClearSelection(HWND, LPRECT, int) - clear selection area 
 
*******************************************************************************/ 
 
#include "windows.h" 
#include "select.h" 
 
/**************************************************************************** 
   FUNCTION: DllMain(HANDLE, DWORD, LPVOID) 
 
   PURPOSE:  DllMain is called by Windows when 
             the DLL is initialized, Thread Attached, and other times. 
             Refer to SDK documentation, as to the different ways this 
             may be called. 
              
             The DllMain function should perform additional initialization 
             tasks required by the DLL.  In this example, no initialization 
             tasks are required.  DllMain should return a value of 1 if 
             the initialization is successful. 
            
*******************************************************************************/ 
BOOL APIENTRY DllMain(HANDLE hInst, DWORD ul_reason_being_called, LPVOID lpReserved) 
{ 
    return 1; 
        UNREFERENCED_PARAMETER(hInst); 
        UNREFERENCED_PARAMETER(ul_reason_being_called); 
        UNREFERENCED_PARAMETER(lpReserved); 
} 
 
 
/**************************************************************************** 
 
    FUNCTION: StartSelection(HWND, POINT, LPRECT, int) 
 
    PURPOSE: Begin selection of region 
 
****************************************************************************/ 
 
INT APIENTRY StartSelection( 
    HWND hWnd, 
    MPOINT ptCurrent, 
    LPRECT lpSelectRect, 
    INT fFlags) 
{ 
    if (lpSelectRect->left != lpSelectRect->right || 
            lpSelectRect->top != lpSelectRect->bottom) 
        ClearSelection(hWnd, lpSelectRect, fFlags); 
 
    lpSelectRect->right = ptCurrent.x; 
    lpSelectRect->bottom = ptCurrent.y; 
 
    /* If you are extending the box, then invert the current rectangle */ 
 
    if ((fFlags & SL_SPECIAL) == SL_EXTEND) 
        ClearSelection(hWnd, lpSelectRect, fFlags); 
 
    /* Otherwise, set origin to current location */ 
 
    else { 
        lpSelectRect->left = ptCurrent.x; 
        lpSelectRect->top = ptCurrent.y; 
    } 
    SetCapture(hWnd); 
    return 1; 
} 
 
/**************************************************************************** 
 
    FUNCTION: UpdateSelection(HWND, POINT, LPRECT, int) - update selection area 
 
    PURPOSE: Update selection 
 
****************************************************************************/ 
 
INT APIENTRY UpdateSelection( 
    HWND hWnd, 
    MPOINT ptCurrent, 
    LPRECT lpSelectRect, 
    INT fFlags) 
{ 
    HDC hDC; 
    SHORT OldROP; 
 
    hDC = GetDC(hWnd); 
 
    switch (fFlags & SL_TYPE) { 
 
        case SL_BOX: 
            OldROP = (SHORT)SetROP2(hDC, R2_NOTXORPEN); 
            MoveToEx(hDC, lpSelectRect->left, lpSelectRect->top, NULL); 
            LineTo(hDC, lpSelectRect->right, lpSelectRect->top); 
            LineTo(hDC, lpSelectRect->right, lpSelectRect->bottom); 
            LineTo(hDC, lpSelectRect->left, lpSelectRect->bottom); 
            LineTo(hDC, lpSelectRect->left, lpSelectRect->top); 
            LineTo(hDC, ptCurrent.x, lpSelectRect->top); 
            LineTo(hDC, ptCurrent.x, ptCurrent.y); 
            LineTo(hDC, lpSelectRect->left, ptCurrent.y); 
            LineTo(hDC, lpSelectRect->left, lpSelectRect->top); 
            SetROP2(hDC, OldROP); 
            break; 
     
        case SL_BLOCK: 
            PatBlt(hDC, 
                lpSelectRect->left, 
                lpSelectRect->bottom, 
                lpSelectRect->right - lpSelectRect->left, 
                ptCurrent.y - lpSelectRect->bottom, 
                DSTINVERT); 
            PatBlt(hDC, 
                lpSelectRect->right, 
                lpSelectRect->top, 
                ptCurrent.x - lpSelectRect->right, 
                ptCurrent.y - lpSelectRect->top, 
                DSTINVERT); 
            break; 
    } 
    lpSelectRect->right = ptCurrent.x; 
    lpSelectRect->bottom = ptCurrent.y; 
    ReleaseDC(hWnd, hDC); 
    return 1; 
} 
 
/**************************************************************************** 
 
    FUNCTION: EndSelection(POINT, LPRECT) 
 
    PURPOSE: End selection of region, release capture of mouse movement 
 
****************************************************************************/ 
 
INT APIENTRY EndSelection( 
    MPOINT ptCurrent, 
    LPRECT lpSelectRect) 
{ 
    lpSelectRect->right = ptCurrent.x; 
    lpSelectRect->bottom = ptCurrent.y; 
    ReleaseCapture(); 
    return 1; 
} 
 
/**************************************************************************** 
 
    FUNCTION: ClearSelection(HWND, LPRECT, int) - clear selection area 
 
    PURPOSE: Clear the current selection 
 
****************************************************************************/ 
 
INT APIENTRY ClearSelection( 
    HWND hWnd, 
    LPRECT lpSelectRect, 
    INT fFlags) 
{ 
    HDC hDC; 
    INT2DWORD OldROP; 
 
    hDC = GetDC(hWnd); 
    switch (fFlags & SL_TYPE) { 
 
        case SL_BOX: 
            OldROP = SetROP2(hDC, R2_NOTXORPEN); 
            MoveToEx(hDC, lpSelectRect->left, lpSelectRect->top, NULL); 
            LineTo(hDC, lpSelectRect->right, lpSelectRect->top); 
            LineTo(hDC, lpSelectRect->right, lpSelectRect->bottom); 
            LineTo(hDC, lpSelectRect->left, lpSelectRect->bottom); 
            LineTo(hDC, lpSelectRect->left, lpSelectRect->top); 
            SetROP2(hDC, OldROP); 
            break; 
 
        case SL_BLOCK: 
            PatBlt(hDC, 
                lpSelectRect->left, 
                lpSelectRect->top, 
                lpSelectRect->right - lpSelectRect->left, 
                lpSelectRect->bottom - lpSelectRect->top, 
                DSTINVERT); 
            break; 
    } 
    ReleaseDC(hWnd, hDC); 
    return 1; 
}