1. JSON轉字符串

var jsonStr = {"name": "xiaoming", "sex": "男"}

JSON.stringify(jsonStr)

2. 數組轉字符串

var arr= ["A", "B", "C", "D"];
var str = arr.toString();       // Returns a string representing the specified object.
var str1 = arr.join()               // Joins all elements of an array into a string.

var str2 = arr.join(",");          // 給每個元素之間加入 "," 隔開,并轉字符串