Dropping a file onto an applications icon

I would like it so that I can drop a file onto my application's icon and then the application would start up with information gleaned from the file.  I'm using MS VC++ 5.0 and have experimented with the WM_DROPFILES message, but that only appears to work once the application has already started.  Any help would be appreciated.
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You have to accept command line arguments in your application to be able to accept a file that is dropped on your icon.  Your main routine should look something like this:

void main(int argc, char* argv[])
   //argc is the argument count
   if (argc > 1)
      //read in your file whose name is in argv[1]
      //or do whatever file manipulation you are doing
      ReadFile( argv[1] );
   //put the rest of your main subroutine in here
tdubroffAuthor Commented:
You get command line args automatically with an AppWizard generated application.

Ronslow, can you be a little more specific?  I have a global application called The App that runs my modal dialog box.  Where do I insert the use of command-line arguments?  I have put an OnDropFiles(HDROP hDrop) message handler in both The App and my dialog box, but that only accepts dropped files after the application has started up.
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tdubroffAuthor Commented:
Include this code in your application's InitInstance

      CCommandLineInfo cmdInfo;

Then look at cmdInfo to determine what to do with the file

SDI and MDI apps already have thie code .. They then call ProcessShellCommand which interprets the command line and sends commands like ID_FILE_NEW etc.  Ida dialog app, you (probably) don't want this last step .. you can check m_nShellCommand for the type of command line given (FileNew is no file dropped, FileOpen is a file was dropped etc).

This can also be used when your app is associated with a file type .. so double clicking on the file will launch your app with the filename as a command line arg, and the m_nShellCommand will be FileOpen and m_strFileName will be the name.

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Thanks for the help Ronslow.  I got it working.
tdubroffAuthor Commented:
Glad to help

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