1.示例
var obj = { a:"hello", b:"world", c:"hehe" } var key = 0; for(var oj in obj) { console.log(oj); console.log(obj[oj]); key++; } console.log(key); console.log(obj.size); console.log(obj.length); console.log(Object.keys(obj)); console.log(Object.keys(obj).length );
2.nodejs 运行结果: