HOWTO: Browse for Folders from the Current Directory

• Microsoft Win32 Application Programming Interface (API)
• Microsoft Windows 2000

SUMMARY

By default, the SHBrowseForFolder API lets the user start at the desktop to browse the shell's namespace and pick a folder. Often, you may prefer that your application start the browse dialog box at a folder that the user is likely to want, such as the current working directory.

To set the browse dialog box's initial selection, the BROWSEINFO structure must contain a callback function. When the callback function is called with the message BFFM_INITIALIZED, it can in turn send a BFFM_SETSELECTION message to set the dialog box's selection to the desired path.

MORE INFORMATION

Following is some sample code that brings up the browse dialog box with the current directory selected. It also displays the path of the currently selected folder in the dialog box's status window.

Sample Code

      #define STRICT
      #include <windows.h>
      #include <shlobj.h>

      int CALLBACK
      BrowseCallbackProc(HWND hwnd,UINT uMsg,LPARAM lp, LPARAM pData) {
         TCHAR szDir[MAX_PATH];

         switch(uMsg) {
            case BFFM_INITIALIZED: {
               if GetCurrentDirectory(sizeof(szDir)/sizeof(TCHAR),
                                      szDir)) {
                  // WParam is TRUE since you are passing a path.
                  // It would be FALSE if you were passing a pidl.
                  SendMessage(hwnd,BFFM_SETSELECTION,TRUE,(LPARAM)szDir);
               }
               break;
            }
            case BFFM_SELCHANGED: {
               // Set the status window to the currently selected path.
               if (SHGetPathFromIDList((LPITEMIDLIST) lp ,szDir)) {
                  SendMessage(hwnd,BFFM_SETSTATUSTEXT,0,(LPARAM)szDir);
               }
               break;
            }
            default:
               break;
         }
         return 0;
      }

      int PASCAL
      WinMain (HINSTANCE hInstance,
               HINSTANCE hPrevInstance,
               LPSTR lpszCmdLine,
               int nCmdShow)
      {
         BROWSEINFO bi;
         TCHAR szDir[MAX_PATH];
         LPITEMIDLIST pidl;
         LPMALLOC pMalloc;

         if (SUCCEEDED(SHGetMalloc(&pMalloc))) {
            ZeroMemory(&bi,sizeof(bi));
            bi.hwndOwner = NULL;
            bi.pszDisplayName = 0;
            bi.pidlRoot = 0;
            bi.ulFlags = BIF_RETURNONLYFSDIRS | BIF_STATUSTEXT;
            bi.lpfn = BrowseCallbackProc;

            pidl = SHBrowseForFolder(&bi);
            if (pidl) {
               if (SHGetPathFromIDList(pidl,szDir)) {
                  MessageBox(NULL,szDir,"Picked",MB_OK);
               }

               // In C++: pMalloc->Free(pidl); pMalloc->Release();
               pMalloc->lpVtbl->Free(pMalloc,pidl);
               pMalloc->lpVtbl->Release(pMalloc);
            }
         }
         return 0;
      } 

Additional query words:

Keywords : kbcode kbLib kbNTOS400 kbWinOS2000 kbSDKWin32 kbWinOS95 kbWinOS98 kbGrpShell
Version : WINDOWS:; winnt:
Platform : WINDOWS winnt
Issue type : kbhowto