問題描述

http.createServer((req,res)=>{ res.write(’hello world’); console.log(typeof res);// obj res.end();});

如何 查看req和res的具體對象類型，這樣可以去文檔中看具體詳細(xì)api.typeof打印出的是object，我希望打印出的是http.ServerResponse

怎么搞

問題解答

打印函數(shù)的類信息:

function classof(obj){ if(typeof(obj)==='undefined')return 'undefined'; if(obj===null)return 'Null'; var res = Object.prototype.toString.call(obj).match(/^[objects(.*)]$/)[1]; if(res==='Object'){res = obj.constructor.name;if(typeof(res)!=’string’ || res.length==0){ if(obj instanceof jQuery)return 'jQuery';// jQuery build stranges Objects if(obj instanceof Array)return 'Array';// Array prototype is very sneaky return 'Object';} } return res;}// Exampleconsole.log(classof(new Date())); // => 'Date'