JavaScript DOM事件(笔记)

<input type="button" value="按钮" onclick="showMessage()">

<input type="button" value="按钮" id="btn2"><script>  var btn2 = document.getElementById('btn2'); //取得btn2按钮对象;  btn2.onclick = function () {        //给btn2添加onclick属性;    alert('这是通过DOM0级添加的事件!');  }  btn2.onclick=null;             //删除onclick属性;</script>

<input type="button" value="按钮" id="btn3"><script>  var btn3 = document.getElementById('btn3');  btn3.addEventListener('click',showMessage,false);    //添加事件程序;  btn3.addEventListener('click',function(){        //添加多个事件程序;    alert(this.value);  },false);  btn3.removeEventListener('click',showMessage,false);  //删除事件程序;</script>

<script>   var btn3 = document.getElementById('btn3');   btn3.attachEvent('onclick',showMessage);      //添加事件;   btn3.detachEvent('onclick',showMessage);      //删除事件;</script>

//将添加和删除事件处理程序封装到对象中并赋值给变量'eventUtil';var eventUtil = {  //添加句柄  addHandler:function(element,type,handler){    //判断DOM2级事件处理程序;    if(element.addEventListener){        element.addEventListener(type,handler,false);    //判断IE浏览器;    }else if(element.attachEvent){      element.attachEvent("on"+type,handler);    //使用DOM0级事件处理程序;    }else{      element['on'+type] = handler;    }  };  //删除句柄  removeHandler:function(element,type,handler){    //判断DOM2级事件处理程序;    if(element.removeEventListener){        element.removeEventListener(type,handler,false);    //判断IE浏览器;    }else if(element.detachEvent){      element.detachEvent("on"+type,handler);    //使用DOM0级事件处理程序;    }else{      element['on'+type] = null;    };  };};//跨浏览器添加事件处理程序;eventUtil.addHandler(btn3,'click',showMessage);

function showMes(event){  alert(event.type);          //onclick;点击事件;  alert(event.target.nodeName);  　　//INPUT;input按钮被触发;  event.stopPropagation();      //停止事件冒泡;}<a href="event.html" onclick="stopGoto();">跳转</a>function stopGoto(event){  event.preventDefault();　　　　　　　//阻止默认行为;}

function showMes(event){  //非IE用event,IE8以下用window.event;  event = event || window.event;    //事件目标兼容;  var ele = event.target || event.srcElement;  //兼容阻止事件冒泡;  if(event.stopPropagation){    event.stopPropagation();  }else{    event.cancleBubble();  };  //兼容取消事件默认行为;  if(event.preventDefault){    event.preventDefault();  }else{    event.returnValue = false;  }}

function getClass(clsName,parent){  var oParent = parent?document.getElementById(parent):document,      eles = [],      elements = oParent.getElementsByTagName('*');  for (var i=0,l=elements.length; i<l; i++){    if(elements[i].className == clsName){      eles.push(elements[i]);    }  }  return eles;}

window.onload = drag;function drag(){  var oTitle = getClass('login_logo_webqq','loginPanel')[0];    //拖拽  oTitle.onmousedown = fnDown;  //关闭弹窗  var oClose = document.getElementById('ui_boxyClose');  oClose.onclick = function(){    document.getElementById('loginPanel').style.display = 'none';  }  //切换状态  var loginState = document.getElementById('loginstate'),    stateList = document.getElementById('loginStatePanel'),    lis = stateList.getElementsByTagName('li'),    stateTxt = document.getElementById('login2qq_state_txt'),    loginStateShow = document.getElementById('login-state_show');  loginState.onclick = function(e){    //阻止冒泡到document使ul隐藏;    e = e || window.event;    if(e.stopPropagation){      e.stopPropagation();    }esle{      e.cancleBubble = true;    }    stateList.style.display = "block";  }  //鼠标滑过/离开和点击状态列表时  for(var i=0,i<lis.length,i++){    lis[i].onmouseover = function(){      this.style.background = "#567";    }    lis[i].onmouseout = function(){      this.style.background = "#fff";    }    lis[i].onclick = function(e){      //阻止冒泡到loginState使stateList显示;      e = e || window.event;      if(e.stopPropagation){        e.stopPropagation();      }esle{        e.cancleBubble = true;      }      var id = this.id;      stateList.style.display = "none";      stateTxt.innerHTML = getClass('stateSelect_text',id)[0].innerHTML;      loginStateShow.className = '';      loginStateShow.className = 'login-state-show '+id;    }  }  document.onclick = function(){    stateList.style.display = "none";  }}//鼠标按下事件;function fnDown(event){  event = event || window.event;  var oDrag = document.getElementById('loginPanel'),      //鼠标按下时,鼠标和面板之间的距离;      disX = event.clientX - oDrag.offsetLeft,      disY = event.clientY - oDrag.offsetTop;  //移动  document.onmouseover = function(event){    event = event || window.event;    fnMove(event,disX,disY);  }  //释放鼠标 document.onmouseup = function(){  document.onmouseover = null;  document.onmouseup = null;  }}//鼠标移动事件;function fnMove (e,posX,posY){  var oDrag = document.getElementById('loginPanel'),      l = e.clientX-posX,      t = e.clientY-posY,      winW = document.documentElement.clientWidth || document.body.clientWidth,   winH = document.documentElement.clientHeight || document.body.clientHeight;   maxW = winW-oDrag.offsetWidth,   maxH = winH-oDrag.offsetHeight; if(l<0){   l = 0; }else if(l>maxW){   l = maxW; } if(t<0){   t = 0; }else if(t>maxH){   t=maxH; }  oDrag.style.left = l+'px';  oDrag.style.top = t+'px';}

var data = ['iPhone5','iPad','三星电脑','谢谢参与'],    timer = null,    flag = 0;window.onload = function(){  var play = document.getElementById('play'),    stop = document.getElementById('stop');  //(鼠标)开始抽奖  play.onclick = palyFun;  stop.onclick = stopFun;  //(键盘Enter)开始抽奖  document.onkeyup = function(event){    event = event || window.event;     if(event.keyCode == 13){      if(flag == 0){        palyFun();        flag = 1;      }else{        stopFun();        flag = 0;      }    }  }}function palyFun(){  var title = document.getElementById('title'),    play = document.getElementById('play');  //清除之前的定时器,放置定时器重复;  clearInterval(timer);　　　　//设置定时器;  timer = setInterval(function(){    //随机数*数组元素个数=数组随机索引;    var random = Math.floor(Math.random()*data.length);    title.innerHTML = data[random];  },50);  play.style.background = "#999";}function stopFun(){  clearInterval(timer);  var paly = document.getElementById('play');  paly.style.background = '#036';  }