obj.onclick = function(e){ var ev = e || window.event; var target = ev.target || ev.srcElement; //具体点到的目标，最内层 var cTarget = currentTarget || this; //对象this始终等于currentTarget }

var Demo = (function(){ var dirc = {}; function bind(eType, func){ if(typeof eType == "string" && typeof func == "function"){ if(typeof dirc[eType] != "undefined"){ dirc[eType].push(func); }else{ dirc[eType] = [func]; } }else{ alert("bind传参有误"); } console.log(dirc); } function trigger(eType){ if(typeof dirc[eType] != "undefined"){ for(var i=0; i < dirc[eType].length; i++){ dirc[eType][i](); } } } function unbind(eType){ if(typeof dirc[eType] != "undefined"){ delete dirc[eType]; } } return { bind : bind, trigger: trigger, unbind : unbind } }()); Demo.bind("hello",function(){alert("hello")}); Demo.bind("hello",function(){alert("bbb")}); Demo.trigger("hello"); Demo.unbind("hello"); Demo.trigger("hello");

function fun(n,o) { console.log(o) return { fun:function(m){ return fun(m,n); } }; } var a = fun(0); a.fun(1); a.fun(2); a.fun(3); //undefined / ? / ? / ? var b = fun(0).fun(1).fun(2).fun(3); //undefined / ? / ? / ? var c = fun(0).fun(1); c.fun(2); c.fun(3); //undefined / ? / ? / ?

if (!Function.prototype.bind) { Function.prototype.bind = function(oThis) { if (typeof this !== "function") { // closest thing possible to the ECMAScript 5 // internal IsCallable function throw new TypeError("TypeError"); } var aArgs = Array.prototype.slice.call(arguments, 1), fToBind = this, fNOP = function() {}, fBound = function() { return fToBind.apply(this instanceof fNOP ? this : oThis || this, aArgs.concat(Array.prototype.slice.call(arguments))); }; fNOP.prototype = this.prototype; fBound.prototype = new fNOP(); return fBound; }; }

//第一种: //找到一个基准值，左边找到大于基准值，右边找到小于基准值的同时，左右换位。继续遍历。 function sort(arr){ return quickSort2(arr,0,arr.length-1); function quickSort2(arr,l,r){ if(l<r){ var mid=arr[parseInt((l+r)/2)],i=l-1,j=r+1; while(true){ while(arr[++i]<mid); while(arr[--j]>mid); if(i>=j)break; var temp=arr[i]; arr[i]=arr[j]; arr[j]=temp; } quickSort2(arr,l,i-1); quickSort2(arr,j+1,r); } return arr; } }

function bubbleSort(arr){ var result = arr, len = result.length; for(var i=0; i < len; i++){ for(var j=0; j < len-1-i; j++){ console.log(++sss); if(result[j]>result[j+1]){ var temp = result[j]; result[j] = result[j+1]; result[j+1] = temp; } } } return result; }

function unique(arr){ var result=[], record = {}; //记录每个元素出现的次数 for(var i=0; i< arr.length; i++){ if(record[arr[i]]){ record[arr[i]]++; }else{ result.push(arr[i]); record[arr[i]]=1; } } return record; }

function Foo() { getName = function() { alert(1); }; return this; } Foo.getName = function() { alert(2); }; Foo.prototype.getName = function() { alert(3); }; var getName = function() { alert(4); }; function getName() { alert(5); } //请写出以下输出结果： Foo.getName(); getName(); Foo().getName(); getName(); new Foo.getName(); new Foo().getName(); new new Foo().getName();

document.domain = 'a.com'; var ifr = document.createElement('iframe'); ifr.src = 'http://script.a.com/b.html'; ifr.style.display = 'none'; document.body.appendChild(ifr); ifr.onload = function(){ var doc = ifr.contentDocument || ifr.contentWindow.document; // 在这里操纵b.html alert(doc.getElementsByTagName("h1")[0].childNodes[0].nodeValue); };

document.domain = 'a.com';

//a.html <iframe id="ifr" src="b.com/index.html"></iframe> <script type="text/javascript"> window.onload = function() { var ifr = document.getElementById('ifr'); var targetOrigin = 'http://b.com'; // 若写成'http://b.com/c/proxy.html'效果一样 // 若写成'http://c.com'就不会执行postMessage了 ifr.contentWindow.postMessage('I was there!', targetOrigin); }; </script> //b.html <script type="text/javascript"> window.addEventListener('message', function(event){ // 通过origin属性判断消息来源地址 if (event.origin == 'http://a.com') { alert(event.data); // 弹出"I was there!" alert(event.source); // 对a.com、index.html中window对象的引用 // 但由于同源策略，这里event.source不可以访问window对象 } }, false); </script>

 var reg = /\w+/g; reg.test(str); str.match(reg);

//获取url参数 var getUrlPara = function(){ var arr = window.location.search.substring(1).split("&"), result = {}; for(var i=0; i < arr.length; i++){ result[arr[i].split("=")[0]] = arr[i].split("=")[1]; } return result; }

var throttle = function(fn, delay){ var timer = null; return function(){ var context = this, args = arguments; clearTimeout(timer); timer = setTimeout(function(){ fn.apply(context, args); }, delay); }; }; var throttleV2 = function(fn, delay, mustRunDelay){ var timer = null; var t_start; return function(){ var context = this, args = arguments, t_curr = +new Date(); clearTimeout(timer); if(!t_start){ t_start = t_curr; } if(t_curr - t_start >= mustRunDelay){ fn.apply(context, args); t_start = t_curr; } else { timer = setTimeout(function(){ fn.apply(context, args); }, delay); } }; };