var obj = {
key1: 'value1', key2: 'value2', key3: 'value3', key4: 'value4'};var keys = [];for (var k in obj) keys.push(k);alert("total " + keys.length + " keys: " + keys);
var obj = {
key1: 'value1', key2: 'value2', key3: 'value3', key4: 'value4'};var keys = [];for (var k in obj) keys.push(k);alert("total " + keys.length + " keys: " + keys);名师互学网 版权所有 (c)2021-2022 ICP备案号：晋ICP备2021003244-6号
