function json2str(o) { 
var arr = []; 
var fmt = function(s) { 
if (typeof s == ‘object‘ && s != null) return json2str(s); 
return /^(string|number)$/.test(typeof s) ? ‘"‘ + s + ‘"‘ : s; 
} 
for (var i in o) arr.push("‘" + i + "‘:" + fmt(o[i])); 
return ‘{‘ + arr.join(‘,‘) + ‘}‘; 
} 

//json2str({a:1,sd:3})
//"{‘a‘:"1",‘sd‘:"3"}"

  来自 ： http://www.jb51.net/article/32825.htm