JS break and continue and return keywords

• break Stop the cycle , Not later

• continue Stop the current cycle , Continue the following cycle ;

    <script>
        for(var i=0;i<5;i++){
            if(i==3){
                break;
            }
            console.log(i);
        }
        for (var i=0;i<5;i++){
            if(i==3){
                continue;
            }
            console.log(i);
        }
    </script>

•  return Stop the function , Can only be used in functions

    function fn(){
            console.log('zhang');
            return;
            console.log('xiaogou');
        }

Why use function return value ： Convenient function reuse

After the function is executed, there is a return value

Don't use return The default return value is undefined

Function return Practical application of

encapsulation $() function

encapsulation getStyle（） function

currentStyle/getComputedStyle--arguments