JSON语法值的获取

JSON-语法-值的获取

获取数据:

　　1. json对象.键名

　　2. json对象[ " 键名 " ]

　　3. 数组对象[ 索引 ]

　　4. 遍历

JSON值的获取

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script>
        //定义基本格式
        var person = {"name":"张三",age: 23,'gender':true};

        //获取name的值
        // let name = person.name;
        var name = person["name"];
        //alert(name)

        //alert(person)
        //2.嵌套格式 {}--->[]
        var persons={"persons":[
                {"name":"张三","age":18,"gender":true},
                {"name":"李四","age":18,"gender":true},
                {"name":"王五","age":18,"gender":false}
            ]
        };
        //获取王五值
        let name1 = persons.persons[2].name;
        // alert(name1)

        //2.嵌套格式 []--->{}
        var ps = [
            {"name":"张三","age":18,"gender":true},
            {"name":"李四","age":18,"gender":true},
            {"name":"王五","age":18,"gender":false}
        ];
        //获取李四值
        alert(ps[1].name)

    </script>
</head>
<body>

</body>
</html>

JSON数据语法遍历

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script>
        //定义基本格式
        var person = {"name":"张三",age: 23,'gender':true};

        var ps = [
            {"name":"张三","age":18,"gender":true},
            {"name":"李四","age":18,"gender":true},
            {"name":"王五","age":18,"gender":false}
        ];

        //获取person对象中所有的键和值
        //for in 循环
      /*  for (var key in person){
            //这样的获取方式不行.因为相当于 person."name"
            // alert(key+":"+person.key)
            alert(key+":"+person[key]);
        }*/

        //获取ps中的所有值
        for (var i = 0;i<ps.length;i++){
            var p = ps[i];
            for (var key in p){
                alert(key+":"+p[key])
            }
        }
    </script>
</head>
<body>

</body>
</html>