=====Accessing the Shell Clipboard=====

//by Richard Russell, October 2010//\\ \\ **Windows Explorer** lets you copy files from one place in the filesystem to another (e.g. from one folder to another, or from one drive to another) by means of **Copy** and **Paste** operations, analogous to how you might copy-and-paste text from one document to another. This article describes how you can access the **Shell Clipboard** from your BASIC program, so you can **paste** files that have been copied in Windows Explorer, or **copy** files that can then be pasted in Windows Explorer.\\ \\ **Pasting** files from the Shell Clipboard uses a similar mechanism to that described in the article [[/Receiving%20dropped%20files|Receiving dropped files]]. The following code checks to see if there are any files on the Shell Clipboard and if so accesses them:\\ 
<code bb4w>
        CF_HDROP = 15
        MAX_PATH = 260

        DIM Buffer% MAX_PATH

        SYS "IsClipboardFormatAvailable", CF_HDROP TO res%
        IF res% THEN
          SYS "OpenClipboard", @hwnd%
          SYS "GetClipboardData", CF_HDROP TO hdata%
          IF hdata% THEN
            SYS "GlobalLock", hdata% TO hdropfiles%
            SYS "DragQueryFile", hdropfiles%, -1, 0, 0 TO nfiles%
            IF nfiles% THEN
              FOR I% = 0 TO nfiles%-1
                SYS "DragQueryFile", hdropfiles%, I%, Buffer%, MAX_PATH
                PRINT $$Buffer%
              NEXT I%
            ENDIF
            SYS "DragFinish", hdropfiles%
            SYS "GlobalUnlock", hdata%
          ENDIF
          SYS "CloseClipboard"
        ENDIF
</code>
Here the filenames are simply printed to the screen. In practice you are likely to want to copy the files and/or to access their contents.\\ \\ **Copying** files to the Shell Clipboard is slightly more involved, because you have to build the necessary data structure yourself. The code to do it is listed below; for convenience it uses the **FNselectfiles** function, to be found in the article [[/Selecting%20multiple%20files|Selecting multiple files]], to select the file(s) to be copied:\\ 
<code bb4w>
        CF_HDROP = 15
        GMEM_ZEROINIT = &40
        GMEM_DDESHARE = &2000

        MAXFILES = 100
        DIM file$(MAXFILES)
        DIM dropfiles{pFiles%, pt{x%,y%}, fNC%, fWide%}

        nfiles% = FNselectfiles("Select one or more files", "*.*", file$())

        IF nfiles% THEN
          size% = DIM(dropfiles{}) + SUMLEN(file$()) + nfiles% + 1
          SYS "GlobalAlloc", GMEM_DDESHARE + GMEM_ZEROINIT, size% TO hdata%
          SYS "GlobalLock", hdata% TO mem%
          !mem% = DIM(dropfiles{})
          P% = mem% + !mem%
          FOR I% = 1 TO nfiles%
            $$P% = file$(I%)
            P% += LEN(file$(I%)) + 1
          NEXT
          SYS "GlobalUnlock", hdata%
          SYS "OpenClipboard", @hwnd%
          SYS "EmptyClipboard"
          SYS "SetClipboardData", CF_HDROP, hdata%
          SYS "CloseClipboard"
        ENDIF
</code>