第一种方法
try{
var array = ["first","second","third","fourth"];
array.forEach(function(item,index){
if(item == "third"){
var a = aaaa;// first second 后就报错，就跳出循环了
throw new Error("ending");//报错，就跳出循环
}else{
log(item);
}
})
}catch(e){
if(e.message == "ending"){
log("结束了") ;
}else{
log(e.message);
}
其它方法详见
https://blog.csdn.net/guxin_duyin/article/details/82980062
