一、JSON基本入门
二、定义JSON对象
建一个html:
<!DOCTYPE html>
<html lang="en">
<head><meta charset="UTF-8"><title>Title</title><script>//1.定义基本格式var person = {"name": "张三", age: 23, 'gender': true};//获取name的值//var name = person.name;var name = person["name"];// alert(name);//alert(person);//2.嵌套格式 {}———> []var persons = {"persons": [{"name": "张三", "age": 23, "gender": true},{"name": "李四", "age": 24, "gender": true},{"name": "王五", "age": 25, "gender": false}]};// alert(persons);//获取王五值var name1 = persons.persons[2].name;// alert(name1);//2.嵌套格式 []———> {}var ps = [{"name": "张三", "age": 23, "gender": true},{"name": "李四", "age": 24, "gender": true},{"name": "王五", "age": 25, "gender": false}];//获取李四值//alert(ps);alert(ps[1].name);</script></head>
<body></body>
</html>
三、遍历获取json对象的值:
<!DOCTYPE html>
<html lang="en">
<head><meta charset="UTF-8"><title>JSON遍历</title><script>//定义json(基本格式),键可以+引号也可以不加var person={"name":"张三",age:23,"gender":true};//2.嵌套格式(数组里面有json对象) []———> {}var ps=[{"name":"张三",age:23,"gender":true},{"name":"王五",age:24,"gender":true},{"name":"李四",age:25,"gender":false}];//3.嵌套格式(json对象里面有数组) {}———> []var persons = {"p": [{"name": "张三2", "age": 23, "gender": true},{"name": "李四2", "age": 24, "gender": true},{"name": "王五2", "age": 25, "gender": false}]};//1.获取person(基本格式)对象中所有的键和值//for in 循环,key是json对象的键，对象.键名这里遍历不管用，要对象[键]才行for (var key in person){//这样的方式获取不行。因为相当于 person."name"//alert(key + ":" + person.key);alert(key+":"+person[key]);}// 2.遍历数组里面的json(重点)//获取ps中的所有值,先遍历数组for(var i=0;i<ps.length;i++){//获取数组里面的每一个json对象var p=ps[i];for (var key in p){alert(key+":"+p[key]);}}// 3.遍历json里面的数组for (var key1 in persons){var json_value_array=persons[key1];for (var i=0;i<json_value_array.length;i++){//获取数组里面的每一个json对象var pi=json_value_array[i];for (var key2 in pi){alert(key2+":"+pi[key2]);}}}</script>
</head>
<body></body>
</html>
