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This time I will bring you a detailed explanation of the steps for JSON object definition and value implementation in JS. What are the precautions for JSON object definition and value implementation in JS. The following is a practical case, let’s take a look. one time.
1.JSON (JavaScript Object Notation) is a simple data format that is more lightweight than xml. JSON is a native JavaScript format, which means that no special API or toolkit is required to process JSON data in JavaScript.
The rules of JSON are simple: an object is an unordered collection of "name:value" pairs. An object starts with "{" (left bracket) and ends with "}" (right bracket). Each "name" is followed by a ":" (colon); "name/value" pairs are separated by "," (comma).
The rules are as follows:
1) Mapping is represented by colon (":"). Name: Value
2) Parallel data are separated by commas (","). Name 1: value 1, name 2: value 2
3) The mapped collection (object) is represented by curly brackets ("{}"). {Name 1: Value 1, Name 2: Value 2}
4) The collection (array) of parallel data is represented by square brackets ("[]").
[
{Name 1: value, name 2: value 2},
{Name 1: value, name 2: value 2}
]
5) The types that element values can have :string, number, object, array, true, false, null
Five writing methods in 2.json:
1) Traditional way to store data and call data
<script type="text/javascript"> //JS传统方式下定义"类" function Person(id,name,age){ this.id = id; this.name = name; this.age = age; } //JS传统方式下创建"对象" var p = new Person(20141028,"一叶扁舟",22); //调用类中的属性,显示该Person的信息 window.alert(p.id); window.alert(p.name); window.alert(p.age); </script>
2) The first style:
<script type="text/javascript"> var person = { id:001, name:"一叶扁舟", age:23 } window.alert("编号:"+person.id); window.alert("用户名:"+person.name); window.alert("年龄:"+person.age); </script>
3) The second style:
<script type="text/javascript"> var p = [ {id:001,name:"一叶扁舟",age:22}, {id:002,name:"无悔",age:23}, {id:003,name:"无悔_一叶扁舟",age:24} ]; for(var i = 0; i < p.length; i++){ window.alert("编号:"+p[i].id); window.alert("用户名:"+p[i].name); window.alert("年龄:"+p[i].age); } </script>
4) The third style:
<script type="text/javascript"> var p = { "province":[ {"city":"福州"}, {"city":"厦门"}, {"city":"莆田"} ] }; window.alert("所在城市:" + p.province[0].city); </script>
5) The fourth style:
<script type="text/javascript"> var p = { "ids":[ {"id":001}, {"id":002}, {"id":003} ], "names":[ {"name":"一叶扁舟"}, {"name":"无悔"}, {"name":"无悔_一叶扁舟"} ] }; for(var i = 0; i < p.names.length; i++){ window.alert("名字:"+p.names[i].name); } for(var i = 0; i < p.ids.length; i++){ window.alert("id:"+p.ids[i].id); } </script>
6) The fifth style:
<script type="text/javascript"> var p = { "province":["福州","厦门","莆田"] }; window.alert("城市的个数:"+p.province.length); window.alert("分别是:\n"); for(var i=0;i<p.province.length;i++){ window.alert(p.province[i]); } </script>
I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the php Chinese website!
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