JS 技能积累

JS 技巧积累判断是否存在于var a b in c字符串转数组新写法var split split,S ,events c

JS 技巧积累

    判断是否存在于
    var a = "b" in c;
    字符串转数组新写法
    var split = "split",S = " ",    events = "click dblclick mousedown mousemove mouseout mouseover mouseup touchstart touchmove touchend touchcancel"[split](S);


 

var h = 2;h = ~~h;//怎么理解?