Talking about the default behavior of js stop event bubbling blocking browser of blocking hyperconnection

In front-end development work, due to browser compatibility and other issues, we often use "stop event bubbling" and "prevent browser default behavior".

1. Stop event bubbling

JavaScript code

// If an event object is provided, this is 1 A mistake IE Browser 
if ( e && e.stopPropagation )
// So it supports W3C Adj. stopPropagation() Method 
e.stopPropagation(); 
else
// Otherwise, we need to use the IE The way to cancel the event bubbling  
window.event.cancelBubble = true;
return false;

2. Block the browser's default behavior

JavaScript code

// If an event object is provided, this is 1 A mistake IE Browser  
if ( e && e.preventDefault ) 
// Block default browser actions (W3C) 
e.preventDefault(); 
else
//IE The way to prevent the default action of functionalists in  
window.event.returnValue = false; 
return false;