JSON详细学习之JSON in JavaScript

<scripttype=
"text/javascript"
src=
"scripts/json/json2.js"
></script>
<scripttype=
"text/javascript"
src=
"scripts/json/jsonmessage.js"
></script>

<script type="text/javascript" src="scripts/json/json2.js"></script>
<script type="text/javascript" src="scripts/json/jsonmessage.js"></script>

一、在javascript中使用JSON创建一个对象

//创建一个空对象
var
JSONObject={}

//创建一个新的对象
var
JSONObject=
new
Object()

//创建一个包含属性的对象，其中名称为字符串，年龄为整型
var
JSONObject={
"name"
:
"kevin"
,
"age"
:23
}

//创建一个空对象
var JSONObject = {}

//创建一个新的对象
var JSONObject = new Object()

//创建一个包含属性的对象，其中名称为字符串，年龄为整型
var JSONObject = {
      "name":"kevin",
      "age":23
}

和java中类似，我们可以通过点(.)操作符取得对象的属性。

var
JSONObject={
"name"
:
"kevin"
,
"age"
:24,
};

alert(
"JSONObject.name:"
+JSONObject.name);
alert(
"JSONObject.age:"
+JSONObject.age);

var JSONObject = {
	"name":"kevin",
	"age":24,
};

alert("JSONObject.name:"+JSONObject.name);
alert("JSONObject.age:"+JSONObject.age);

二、在javascript中使用JSON创建数组对象

创建一个Student对象，里面包含两个数组对象,每个数组对象中，包含Student对象的属性。

var
student={
//第一个数组对象Class
"Class"
:[
{
"name"
:
"kevin"
,
"className"
:
"java"
,
"age"
:23
},
{
"name"
:
"yang"
,
"className"
:
"java"
,
"age"
:24
}
],
//第二个数组对象
"Score"
:[
{
"name"
:
"shower"
,
"score"
:100
},
{
"name"
:
"zheng"
,
"score"
:100
}
]
}

var
i=0;

for
(i=0;i<student.Class.length;i++){
alert(
"student.Class["
+i+
"].name===>"
+student.Class[i].name);
alert(
"student.Class["
+i+
"].className===>"
+student.Class[i].className);
alert(
"student.Class["
+i+
"].age===>"
+student.Class[i].age);
}

for
(i=0;i<student.Score.length;i++){
alert(
"student.Score["
+i+
"].name===>"
+student.Score[i].name);
alert(
"student.Score["
+i+
"].score===>"
+student.Score[i].score);
}

var student = {
	//第一个数组对象Class
	"Class":[
		{
			"name":"kevin",
			"className":"java",
			"age":23
		},
		{
			"name":"yang",
			"className":"java",
			"age":24
		}	
	],
	//第二个数组对象
	"Score":[
		{
			"name":"shower",
			"score":100
		},
		{
			"name":"zheng",
			"score":100
		}
	]
}

var i=0;

for(i=0;i<student.Class.length;i++){
	alert("student.Class["+i+"].name===>"+student.Class[i].name);
	alert("student.Class["+i+"].className===>"+student.Class[i].className);
	alert("student.Class["+i+"].age===>"+student.Class[i].age);
}

for(i=0;i<student.Score.length;i++){
	alert("student.Score["+i+"].name===>"+student.Score[i].name);
	alert("student.Score["+i+"].score===>"+student.Score[i].score);
}

三、使用JSON在javascript中创建消息

//createaStudentObject
var
Student={
"Math"
:[{
"name"
:
"kevin"
,
"mark"
:70,
"age"
:23
},{
"name"
:
"smart"
,
"mark"
:40,
"age"
:25
}
],
"Science"
:[{
"name"
:
"kevin2"
,
"mark"
:70,
"age"
:23
},{
"name"
:
"smart2"
,
"mark"
:40,
"age"
:25
}
]
}

//printarrayvalue
var
i=0;
var
array=
new
Array();

for
(i=0;i<Student.Math.length;i++){
array.push(Student.Math[i].name);
array.push(Student.Math[i].mark);
array.push(Student.Math[i].age);
}

for
(i=0;i<Student.Science.length;i++){
array.push(Student.Science[i].name);
array.push(Student.Science[i].mark);
array.push(Student.Science[i].age);
}
alert(
"array==>"
+array);

//ThismethodproduceaJSONtextfromaJavaScriptvalue.
//这个方法将一个JavaScript值转换为一个JSON字符串
alert(
"array.toJSONString()==>"
+array.toJSONString());
alert(
"String.parseJSON==>"
+array.toJSONString().parseJSON());
var
data2=array.toJSONString().parseJSON();
if
(data2
instanceof
Array){
alert(
"Array"
);
}