Convert String to JSON object :

1    var res = JSON.parse(data); 
or
2    var res = data.parseJSON();
or
3    var res = eval('('+ data +')');

Use JSON.stringify() to convert into a string for subsequent use.

Try to use JSON.parse, eval is not recommended;
Try to add try...catch, the probability of errors when converting JSON to objects is quite high, such as unescaped characters and too many nesting levels;

try{

var myObject = JSON.parse(data);

} catch(e){

console.log(e);

}

The backend sets the Content-Type of the response header to application/json, and the data outputs a string in json format. The frontend automatically obtains the JSON object, which can be processed as an ordinary js object.

var data=[{"site_name":"aaaa","site_keywords":"bbbb","site_beian":"闽ICP备8888888888号","site_description":"ccccc","site_statistic":"<a>wsdfadfasdfasdfasdfasdf</a>"}];

console.log(JSON.stringify(data));