1方式一 !("key" in obj)
方式二 obj.hasOwnProperty("key") //obj为json对象。
2获取不确定键的值
for(var key in jsona.data) {
alert("对应的值是:" + jsona.data[key].fromName);
}
var jsona = {
"data": {
"李梅_7": {
"fromId": 7,
"toId": 68,
"fromName": "李梅",
"count": 2,
"groupId": null,
"groupName": null,
"type": 0
},
"gisnew_67": {
"fromId": 67,
"toId": 68,
"fromName": "gisnew",
"count": 1,
"groupId": null,
"groupName": null,
"type": 0
}
},
"code": 1,
"msg": "获取新消息成功!"
}