title: C# How to set Transparent key and do not allow click-through?
body: <p>Well, I know how to set the transparent key,</p>
  
  <p>but if i click the transparent region, it clicks through the form.
  is it possible to disabling click through?</p>
  
  <p>hmm.. I think this question is similar as 
  <a href="https://stackoverflow.com/questions/2547425/c-sharp-winforms-transparent-control-allowing-clickthrough">C# Winforms Transparent Control allowing Clickthrough</a></p>
  
  <p>but i do not understand the answer, what value should i change to 1???</p>