javascript中将Object转换为String函数代码 (json str)

function obj2str(o){ 
var r = []; 
if(typeof o =="string") return "\""+o.replace(/([\'\"\\])/g,"\\$1").replace(/(\n)/g,"\\n").replace(/(\r)/g,"\\r").replace(/(\t)/g,"\\t")+"\""; 
if(typeof o == "object"){ 
if(!o.sort){ 
for(var i in o) 
r.push(i+":"+obj2str(o[i])); 
if(!!document.all && !/^\n?function\s*toString\(\)\s*\{\n?\s*\[native code\]\n?\s*\}\n?\s*$/.test(o.toString)){ 
r.push("toString:"+o.toString.toString()); 
} 
r="{"+r.join()+"}" 
}else{ 
for(var i =0;i<o.length;i++) 
r.push(obj2str(o[i])) 
r="["+r.join()+"]" 
} 
return r; 
} 
return o.toString(); 
}