JS Cancel Carriage Return Event

Recently in writing a JS gadget, which involves such a function: In the textarea after the completion of editing things, hit enter, send messages, empty textarea;
But there is a bug: After hitting enter, TEXTAREA will have a newline character;
Want to go, it should be this return hit, after emptying the TextArea method call, the event continues, so the line break is treated as input, entered the textarea;

How do I get this return event to be canceled after emptying the textarea?

Find this article on the Internet JS block event bubbling, so in the code add a sentence

Obj.preventdefault ();

it was solved;

The demo is as follows:

 
 
 
JS Cancel Carriage Return Event