摘要:
//for in循环遍历var objs={"username":"hh","age":"20","sex":"boy"}for(i in objs){ console.log(i); //uesername age sex console.log(objs[i]); //hh 20 boy 这里用 阅读全文
摘要:
//in运算符(用来判断一个属性是否在对象里面)var obj={"username":"hh"};console.log("username" in obj); //truevar arr=[11,2223,333,4,44]; //如果是数组,属性为它的下标或者索引console.log(1 i 阅读全文