每日一个js实例3-不同格式json解析

index1.json:

{
  "A":[
        {"name":"zhangsan"},
        {"sex":"man"},
        {"age":23}
      ],
  "B":[3,4,1,23,54]
 }

<script type="text/javascript">
    $.ajax({
        url:"../data/index1.json",
        type:"get",
        dataType:"json",
        success:function(data){
            //A
            alert(data);//[object object]对象集合
            alert(typeof data);//object
            alert(data.A);//[object object],[object object],[object object],
           alert(data.A[0]);//[object object]
             alert(typeof data.A);//object
            alert(data.A.name);//undefined
            alert(data.A.length);//3
           alert(data.A[0].name);//zhangsan
           alert(data.A[1].name);//undefined,之所以出现undefined,是因为json中[]内的每个{}也是一个对象数组了
            alert(data.A[1].sex);//man
            $('#json').html(data.A[0].name);//zhangsan
            for(var i in data.A){
                for(var j in data.A[i]){
                    document.write(i);//0,1.2
                    document.write(j);//name,sex,age
                   document.write(data.A[i]);//[object object],[object object],[object object]
                    document.write(data.A[j]);//undefine dundefine undefine
                   document.write(data.A[i][j]);//zhangsan,man,23
                   document.write(j+":"+data.A[i][j]+"<br/>");//打印data.A所有数据
                }
            }

            //B
            alert(data.B);//3,4,1,23,54
            alert(data.B[0]);//3
            alert(typeof data.B);//object
           for(var i=0;i<data.B.length;i++){
               document.write(i+":"+data.B[i]+"<br/>")
           }
           for(var i in data.B){
               document.write(i+":"+data.B[i]+"<br/>")
           }//以上两种循环方式结果一样，打印data.B所有数据
        }
    })
 </script>

index2.json:

{
  "ecgcode":[3,4,1,23,54],
  "ecg":
  {
    "id":1,
    "createDate":null,
    "updateDate":1476172420000,
    "uploadTime":1474445600000
    }
}

<script type="text/javascript">
    $.ajax({
        url:"../data/index2.json",
        type:"get",
        dataType:"json",
        success:function(data){
           document.write(data.ecg);//[object Object]
           document.write(data.ecg.id);//1
           for(var i in data.ecg){
               document.write(i+":"+data.ecg[i]+"<br/>");//打印data.ecg所有数据
           }
        }
    })
</script>

index3.json:

[
  {
    "_id": "58008a1b62ee553fefe76363",
    "index": 0,
    "tags": ["culpa","consequat","irure","aliqua","elit","amet","exercitation"],
    "friends": [
      {"id": 0,"name": "Lana Mathis"},
      {"id": 1,"name": "Molina Wade"},
      {"id": 2,"name": "Finley Potter"}
    ],
    "greeting": "Hello, Anita Kerr! You have 3 unread messages.",
    "favoriteFruit": "strawberry"
  },
  {
    "_id": "58008a1be00be2f90fda3738",
    "index": 1,
    "tags": ["ullamco","laboris","nulla","pariatur","non","excepteur","aliqua"],
    "friends": [
      {"id": 0,"name": "Malinda Bridges"},
      {"id": 1, "name": "Carrillo Le"},
      {"id": 2,"name": "Bates Ortega"}
    ],
  }
]

<script type="text/javascript">
    $.ajax({
        url:"../data/index3.json",
        type:"get",
        dataType:"json",
        success:function(data){
           alert(data);//[object Object]*5,有5个{}
            alert(data[0]);//[object Object]
            alert(data[0].index);//0
           alert(data[1].tags);//打印所有tags值
           alert(data[1].friends);//[object pbject],[object pbject],[object pbject]
            for(var i in data[1].friends){
               for(var j in data[1].friends[i]){
                   document.write(j+":"+data[1].friends[i][j]+"<br/>");//打印data[4].friends数据
               }
            }
            for(var i in data){
                for(var j in data[i]){
                    document.write(i);//0,1,2,3,4
                    document.write(j);//所有键值队的键
                    document.write(data[i]);//[object pbject],[object pbject],[object pbject]
                    document.write(data[j]);//undefine undefine undefine
                    document.write(data[i][j]);//zhangsan,man,23
                     document.write(j+":"+data[i][j]+"<br/>");//打印data所有数据
                }
            }
        }
    })
</script>