title: Excel macro: Browse Excel file and use its worksheet data
body: <p>I write a script like this:</p>
  
  <pre><code>Sub Button_Click()
      objFile = Application.GetOpenFilename(fileFilter:="All Files (* . *) , * . * ") ' choose load path
      .....
  
      Call main_function
  End Sub
  </code></pre>
  
  <p>This is the script of an Excel macro button to let the user browse the file. Actually, I want use this to load an Excel file and use that Excel file's data in the <code>main_function</code>(the current excel).</p>
  
  <p>How can I do this?</p>