【一】用var 声明多个变量，比每个变量都用var快多了
复制代码 代码如下:
var sScrollTop = document.body.scrollTop || document.documentElement.scrollTop,
sWindow_h = document.documentElement.clientHeight,
t_h = parseInt(this.getCss(this.getId('gy_photoBox_head'),'height')),
hold_h = sWindow_h - t_h - 20,
width = this.nImgWidth ,
height = this.nImgHeight;
【二】Dom事件优化，在 window.onresize时，定义个定时器,setTimeout，可以防止事件频繁调用
复制代码 代码如下:
windowResize:function(){
var _that = this,
_timer = null;
// 函数节流
window.onresize = function(){
clearTimeout(_timer);
_timer = setTimeout(function(){
if( _that.tools.getId('gy_photoBox')){
_that.setBoxCss();
}
},100);
}
}
【三】图片加载的处理函数
复制代码 代码如下:
/*
@ src [String] 图片的地址
@ success [Function] 图片加载成功的回调函数
@ error [Function] 图片加载失败的回调函数
*/
imgLoading:function(opt){
var _img = new Image(),
_that = this;
_img.onload = function(){
_that.nImgWidth = this.width;
_that.nImgHeight = this.height;
if(typeof opt.success == 'function'){
setTimeout(function(){
opt.success();
},300);
}
}
_img.onerror = function(){
if(typeof opt.error){
opt.error();
}
}
// 注意：要放在onload事件下面，否则ie会出现BUG
_img.src = opt.src;
}
源代码：
复制代码 代码如下:
/*
author:laoguoyong
*/
(function(){
/* -------------------------简单的选择器-----------------------
@ 参数 [string]
---------------------------------------
★-只支持以下选择-★
@ 支持一级选择器：如'#id','.class','p'
@ 支持后代选择，如 '.class p','body span'
@ 支持子元素选择，如 '.class>p','body>span'
----------------------------------------
@ return [Array]
*/
var selector = function(str){
// 定义元素数组
var elem = [];
/* 私有方法
------------------------*/
//返回是id的元素
function _getId(id){
return document.getElementById(id);
}
//返回存在此类名的元素-元素
function _getByClassName(className,parent){
var class_array = [],
node = parent != undefined&&parent.nodeType==1?parent.getElementsByTagName('*'):document.getElementsByTagName('*'),
reg = new RegExp("(^|s)"+className+"(s|$)");
for(var n=0,i=node.length;n<i;n++){
if(reg.test(node[n].className)){
class_array.push(node[n]);
}
}
return class_array;
}
//一级选择，如 '#id','p','.class'
// return [Array]
function _getDom(s){
var array_elem = [];
if (s.indexOf('#')==0){
array_elem.push(_getId(s.slice(1)));
}
else if(s.indexOf('.')==0){
array_elem = array_elem.concat(_getByClassName(s.slice(1)));
}
else{
var tag = document.getElementsByTagName(s);
for(var n=0,i=tag.length;n<i;n++){
array_elem.push(tag[n]);
}
}
return array_elem;
}
/*
@ arry_elm [Array] : 元素数组，如 ['.demo','p'] ，选择的是.demo下面的p元素，至于是选择后代还是子代，请看第2个参数解释
@ r [String] -可选（不传默认为选择后代）: '>'，是选择子代元素;
--------------------------
@ return [Array]
*/
function _query(array_elem,r){
var node = array_elem,
type_name = node[0].match(/#/)?'id_'+node[0].slice(1):node[0].match(/./)?'className_'+node[0].slice(1):'tagName_'+node[0],
child = _getDom(node[1]),
type = type_name.split('_'),
len = document.getElementsByTagName('*').length,
reg = new RegExp("(^|s)"+type[1]+"(s|$)");;
for(var i=0,j=child.length;i<j;i++){
var par = child[i].parentNode;
for(var n=0;n<len;n++){
if(par.nodeType == 9){
break;
}
if(reg.test(par[type[0]])){
elem.push(child[i]);
break;
}else{
if(r == '>') break;
par = par.parentNode;
}
}
}
}
/* 接口
-----------------------*/
var elemStr = str.replace(/(^s+)|(s+$)/,'');
if(document.querySelectorAll){
var dom = document.querySelectorAll(elemStr);
for(var n=0,len=dom.length;n<len;n++){
elem.push(dom[n]);
}
}else{
var split = /[>s]/g.exec(elemStr);
if(split){
var node = elemStr.split(split[0]);
_query(node,split[0]);
}else{
elem = elem.concat( _getDom(elemStr) );
}
}
return elem;
}
/* 弹窗功能构造函数
-----------------------*/
function LGY_photoBox(option){
this.opt = option;
this.oTarget = typeof option.target == 'object'?option.target:selector(option.target);
if(!this.oTarget) return;
this.nLen = this.oTarget.length; //总个数
this.aBigimg_src = []; //大图数据数组
this.aTitle = []; //标题数据数组
this.nIndex = 0; //索引
this.nImgWidth = 0; //动态获取图片的宽
this.nImgHeight = 0; //动态获取图片的高
this.nDelay = 0.2;
this.intit();
}
LGY_photoBox.prototype = {
intit:function(){
var _that = this;
this.getData();
for(var n=0;n<this.nLen;n++){
this.oTarget[n].index = n;
this.oTarget[n].onclick = function(e){
_that.createCover();
var e = _that.tools.getEvent(e),
target = _that.tools.getTarget(e);
// 设置浏页面没有滚动条出现
_that.tools.setCss(document.documentElement,{'height':'100%','overflow-y':'hidden','overflow-x':'hidden'});
// 获取当时索引
_that.nIndex = this.index;
//首次判断
_that.firstLoad(_that.aBigimg_src[_that.nIndex],function(){
//插入结构
_that.createBoxDom();
//关闭
_that.tools.getId('gy_photoBox_close').onclick = function(){
_that.removeBox();
}
// 判断左右按钮显示
_that.btnIsShow();
// 上一张
_that.btnPrev();
// 下一张
_that.btnNext();
// 加载图片
_that.imgChange(_that.aBigimg_src[_that.nIndex]);
});
// 重置窗口大小
_that.windowResize();
// 键盘事件
_that.keyEvent();
//阻止跳转
return false;
}
}
},
createBoxDom:function(){
var doc = document,
exHtml = '',
boxHtml = doc.createElement('div');
boxHtml.id = 'gy_photoBox';
doc.body.appendChild(boxHtml);
if(typeof this.opt.appendHTML == 'string'){
exHtml = this.opt.appendHTML;
}
boxHtml.innerHTML = '<div id="gy_photoBox_prev"></div>'+
'<div id="gy_photoBox_next"></div>'+
'<span id="gy_photoBox_close"></span>'+
'<div id="gy_photoBox_head">'+exHtml+'</div>'+
'<div id="gy_photoBox_main">'+
'<img id="gy_photoBox_img_loading" src="http://www.pconline.com.cn/blank.gif" />'+
'<img id="gy_photoBox_img" />'+
'<div id="gy_photoBox_infor">'+
'<span id="gy_photoBox_num">'+
'<strong id="gy_photoBox_index"></strong>'+
'/'+this.nLen+
'</span>'+
'<p id="gy_photoBox_title"></p>'+
'</div>'+
'</div>';
},
createCover:function(){
// 创建覆盖层
var doc = document,
coverHtml = doc.createElement('div');
coverHtml.id = 'gy_photoBox_cover';
doc.body.appendChild(coverHtml);
//设置覆盖层的样式
this.tools.setCss(this.tools.getId('gy_photoBox_cover'),{'height':(doc.body.scrollTop || doc.documentElement.scrollTop)+(doc.documentElement.clientHeight)+'px'});
},
setBoxCss:function(){
var doc = document,
nScrollTop = doc.body.scrollTop || doc.documentElement.scrollTop,
nWindow_h = doc.documentElement.clientHeight,
eBox_head_h = this.tools.getId('gy_photoBox_head').clientHeight,
eBox = this.tools.getId('gy_photoBox'),
eBoxPadding = 10,
hold_h = nWindow_h - eBoxPadding - 50 - eBox_head_h,
width = this.nImgWidth ,
height = this.nImgHeight;
// alert('nWindow_h:'+nWindow_h+'-'+'eBoxPadding:'+eBoxPadding+'-'+'eBox_head_h:'+eBox_head_h);
// 图片大小超过可见范围，进行缩放
if(this.nImgHeight>hold_h){
height = hold_h,
width = Math.ceil(this.nImgWidth*(height/this.nImgHeight));
}
//设置盒子在整个页面居中
this.tools.setCss(eBox,{'width':width+'px',
'height':eBox_head_h + height + 'px',
'margin-left':-(width+eBoxPadding)/2+'px',
'top':nScrollTop+(nWindow_h-height-eBoxPadding)/2+'px'});
this.tools.setCss(this.tools.getId('gy_photoBox_main'),{'width':width+'px','height':height + 'px'});
//设置覆盖层的样式
this.tools.setCss(this.tools.getId('gy_photoBox_cover'),{'height':nScrollTop+doc.documentElement.clientHeight+'px'});
},
removeBox:function(){
var doc = document;
if(this.tools.getId('gy_photoBox')){
doc.body.removeChild(this.tools.getId('gy_photoBox'));
}
if(this.tools.getId('gy_photoBox_cover')){
document.body.removeChild(this.tools.getId('gy_photoBox_cover'));
}
this.tools.setCss(document.documentElement,{'height':'auto','overflow-y':'auto','_overflow-y':'scroll','overflow-x':'auto'});
},
getData:function(){
for(var n=0;n<this.nLen;n++){
var src = this.oTarget[n].getAttribute('href'),
title = this.oTarget[n].getAttribute('title');
this.aBigimg_src.push(src);
if(!title) title = '';
this.aTitle.push(title);
}
},
btnIsShow:function(){
this.tools.setCss(this.tools.getId('gy_photoBox_prev'),{'display':'block'});
this.tools.setCss(this.tools.getId('gy_photoBox_next'),{'display':'block'});
if(this.nIndex == 0) this.tools.setCss(this.tools.getId('gy_photoBox_prev'),{'display':'none'});
if(this.nIndex == (this.nLen-1)) this.tools.setCss(this.tools.getId('gy_photoBox_next'),{'display':'none'});
},
imgChange:function(){
var _that = this,
_src = this.aBigimg_src[this.nIndex],
eLoadingTips = this.tools.getId('gy_photoBox_img_loading'),
eImg = this.tools.getId('gy_photoBox_img'),
eTitle = this.tools.getId('gy_photoBox_title'),
eInfor = this.tools.getId('gy_photoBox_infor');
// 显示loading图片
this.tools.setCss(eLoadingTips,{'display':'block'});
this.tools.setCss(eInfor,{'display':'none'});
// 判断左右按钮显示
this.btnIsShow();
// 图片加载处理
this.imgLoading({
'src':_src,
'success':function(){
_that.tools.setCss(eLoadingTips,{'display':'none'});
_that.tools.setCss(eInfor,{'display':'block'});
// 设置真实图片路径，标题，当前页码
eImg.src = _src;
eTitle.innerHTML = _that.aTitle[_that.nIndex];
_that.tools.getId('gy_photoBox_index').innerHTML = (_that.nIndex+1);
// 设置样式
_that.setBoxCss();
// 弹窗呈现
_that.tools.setCss(_that.tools.getId('gy_photoBox'),{'visibility':'visible'});
if(_that.tools.getId('gy_photoBox_firstLoad')){
document.body.removeChild(_that.tools.getId('gy_photoBox_firstLoad'));
}
// 每次切换执行的回调函数
if(typeof _that.opt.onChange == 'function'){
_that.opt.onChange({'src':_src,'index':_that.nIndex,'title':_that.aTitle[_that.nIndex]});
}
},
'error':function(){
setTimeout(function(){
_that.tools.setCss(eLoadingTips,{'display':'none'});
},200);
eImg.src = 'gyPhotoBox/error.png';
eTitle.innerHTML = '暂无相关图片';
_that.nImgWidth = 400;
_that.nImgHeight = 300;
_that.setBoxCss();
_that.tools.setCss(_that.tools.getId('gy_photoBox'),{'visibility':'visible'});
if(_that.tools.getId('gy_photoBox_firstLoad')){
document.body.removeChild(_that.tools.getId('gy_photoBox_firstLoad'));
}
}
});
},
btnPrev:function(){
var _that = this;
this.tools.getId('gy_photoBox_prev').onclick = function(){
_that.nIndex--;
_that.imgChange();
}
},
btnNext:function(){
var _that = this;
this.tools.getId('gy_photoBox_next').onclick = function(){
_that.nIndex++;
_that.imgChange();
}
},
keyEvent:function(){
var _that = this;
document.onkeydown = function(e){
var e = e || window.event;
switch(e.keyCode){
case 37:{
if(_that.nIndex != 0&&_that.tools.getId('gy_photoBox_prev')){
_that.nIndex--;
_that.imgChange();
}
};break;
case 39 :{
if(_that.nIndex != (_that.nLen-1)&&_that.tools.getId('gy_photoBox_next')){
_that.nIndex++;
_that.imgChange();
}
};break;
case 27:{
_that.removeBox();
};break;
}
}
},
/*
@ src [String] 图片的地址
@ success [Function] 图片加载成功的回调函数
@ error [Function] 图片加载失败的回调函数
*/
imgLoading:function(opt){
var _img = new Image(),
_that = this;
_img.onload = function(){
_that.nImgWidth = this.width;
_that.nImgHeight = this.height;
if(typeof opt.success == 'function'){
setTimeout(function(){
opt.success();
},300);
}
}
_img.onerror = function(){
if(typeof opt.error){
opt.error();
}
}
// 注意：要放在onload事件下面，否则ie会出现BUG
_img.src = opt.src;
},
firstLoad:function(src,callback){
var _that = this,
html = document.createElement('div');
html.id = 'gy_photoBox_firstLoad';
document.body.appendChild(html);
this.tools.setCss(this.tools.getId('gy_photoBox_firstLoad'),{'top':(document.body.scrollTop || document.documentElement.scrollTop)+(document.documentElement.clientHeight/2) +'px'});
if(typeof callback == 'function') {
callback();
}
},
windowResize:function(){
var _that = this,
_timer = null;
// 函数节流
window.onresize = function(){
clearTimeout(_timer);
_timer = setTimeout(function(){
if( _that.tools.getId('gy_photoBox')){
_that.setBoxCss();
}
},100);
}
},
tools:function(){
return{
getEvent:function(e){
return e || window.event;
},
getTarget:function(e){
return e.target || e.srcElement;
},
preventDefault:function(e){
e.preventDefault?e.preventDefault():e.returnValue = false;
},
getId:function(id){
return document.getElementById(id);
},
getCss:function(node,value){
return node.currentStyle?node.currentStyle[value]:getComputedStyle(node,null)[value];
},
setCss:function(node,val){
for(var v in val){
node.style.cssText += ';'+ v +':'+val[v];
}
}
}
}()
}
window.LGY_photoBox = LGY_photoBox;
})();
最终效果图：
