C form click event did not respond

C# New people , I want to be a translator to practice my hand , Find out Click There was no response to the incident ...

One 、 Event writing completed ( Want to use MessageBox Test it , It didn't respond )

Two 、 Event binding complete

however , Click still no response ....

3、 ... and 、 Find the problem （MouseDown Drag and drop the title bar in the event ）

 

 

Found through debugging , My program process MouseDown After the event , No more click, I don't understand it yet , After removal, it can operate normally click event .

It reminds me of Android Of onEventTouch Method , When onEventTouch The return value is true when , Then the event will stop here , Consumption complete . It may have a similar mechanism !

New people ask for advice , If there is any mistake, please point out ！ Thank you very much ！