js json:
JSON.parse() //转为json对象。
JSON.stringify() //转为JSON字符串。
举例：
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>js json举例</title>
</head>
<body>
<p id="demo"></p>
<script>
var text = '{ "date" : [' +
'{ "key":"info1" , "valmain":"main_info1" },' +
'{ "key":"info2" , "valmain":"main_info2" },' +
'{ "key":"info3" , "valmain":"main_info3" } ]}';
jsonobj = JSON.parse(text);
document.getElementById("demo").innerHTML ="-->"+ jsonobj.date[2].key + " " + jsonobj.date[2].valmain;
</script>
</body>
</html>
结果：-->info3 main_info3
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>js json举例</title>
</head>
<body>
<p id="demo"></p>
<script>
var text = '{ "date" : [' +
'{ "key":"info1" , "valmain":"main_info1" },' +
'{ "key":"info2" , "valmain":"main_info2" },' +
'{ "key":"info3" , "valmain":"main_info3" } ]}';
jsonstr = JSON.stringify(text);
document.getElementById("demo").innerHTML ="-->"+ jsonstr;
</script>
</body>
</html>
结果：-->"{ \"date\" : [{ \"key\":\"info1\" , \"valmain\":\"main_info1\" },{ \"key\":\"info2\" , \"valmain\":\"main_info2\" },{ \"key\":\"info3\" , \"valmain\":\"main_info3\" } ]}"
举例二：重点常用：
存储：
sessionStorage.setItem("userInfo",JSON.stringify(this.$userInfo));
跳转后获取：
var userInfo = JSON.parse(sessionStorage.getItem("userInfo"));