[前端]JavaScript瀑布流

学习了极客学院JavaScript瀑布流实例，实现鼠标下拉图片自动加载效果，和百度图片效果类似http://image.baidu.com/channel/wallpaper。
[TOC]
- HTML

"en">

    "UTF-8">
    
    "stylesheet" type="text/css" href="css/style.css">
    <script type="text/javascript" src="js/app.js">script>


    <div id="container">
        <div class="box">
              <div class="box_img"> "images/1.jpg"  alt="">div>
        div>
        <div class="box">
              <div class="box_img"> "images/2.jpg"  alt="">div>
        div>
        <div class="box">
              <div class="box_img"> "images/3.jpg"  alt="">div>
        div>
        <div class="box">
              <div class="box_img"> "images/4.jpg"  alt="">div>
        div>
        <div class="box">
              <div class="box_img"> "images/5.jpg"  alt="">div>
        div>
    <div class="box">
              <div class="box_img"> "images/6.jpg"  alt="">div>
        div>
        <div class="box">
              <div class="box_img"> "images/7.jpg"  alt="">div>
        div>
        <div class="box">
              <div class="box_img"> "images/8.jpg"  alt="">div>
        div>
        <div class="box">
              <div class="box_img"> "images/9.jpg"  alt="">div>
        div>
        <div class="box">
              <div class="box_img"> "images/10.jpg"  alt="">div>
        div>

        <div class="box">
              <div class="box_img"> "images/1.jpg"  alt="">div>
        div>
        <div class="box">
              <div class="box_img"> "images/2.jpg"  alt="">div>
        div>
        <div class="box">
              <div class="box_img"> "images/3.jpg"  alt="">div>
        div>
        <div class="box">
              <div class="box_img"> "images/4.jpg"  alt="">div>
        div>
        <div class="box">
              <div class="box_img"> "images/5.jpg"  alt="">div>
        div>
    <div class="box">
              <div class="box_img"> "images/6.jpg"  alt="">div>
        div>
        <div class="box">
              <div class="box_img"> "images/7.jpg"  alt="">div>
        div>
        <div class="box">
              <div class="box_img"> "images/8.jpg"  alt="">div>
        div>
        <div class="box">
              <div class="box_img"> "images/9.jpg"  alt="">div>
        div>
        <div class="box">
              <div class="box_img"> "images/10.jpg"  alt="">div>
        div>
        <div class="box">
              <div class="box_img"> "images/1.jpg"  alt="">div>
        div>
        <div class="box">
              <div class="box_img"> "images/2.jpg"  alt="">div>
        div>
        <div class="box">
              <div class="box_img"> "images/3.jpg"  alt="">div>
        div>
        <div class="box">
              <div class="box_img"> "images/4.jpg"  alt="">div>
        div>
        <div class="box">
              <div class="box_img"> "images/5.jpg"  alt="">div>
        div>
    <div class="box">
              <div class="box_img"> "images/6.jpg"  alt="">div>
        div>
        <div class="box">
              <div class="box_img"> "images/7.jpg"  alt="">div>
        div>
        <div class="box">
              <div class="box_img"> "images/8.jpg"  alt="">div>
        div>
        <div class="box">
              <div class="box_img"> "images/9.jpg"  alt="">div>
        div>
        <div class="box">
              <div class="box_img"> "images/10.jpg"  alt="">div>
        div>


    div>

• CSS

*{
     margin: 0px;
     padding: 0px;
}

#container{
      position: relative;
}

.box{
      padding: 5px;
      float: left;
}
.box_img{
      padding: 5px;
      border: 1px solid #cccccc;
      box-shadow: 0 0 5px #ccc;
      border-radius: 5px;
}

.box_img img{
     width: 150px;
     height:auto;
}

• js

window.onload=function(){
      imgLocation("container","box");
      var imgData={
          "data":[
              {"src":"2.jpg"},
              {"src":"3.jpg"},
              {"src":"4.jpg"},
              {"src":"5.jpg"},
              {"src":"6.jpg"},
              {"src":"7.jpg"},
              {"src":"8.jpg"},
          ]
      };
      window.onscroll=function(){
        if (checkFlag()) {
            var cparent=document.getElementById("container");
            for (var i = 0; i < imgData.data.length; i++) {
                 var ccontent=document.createElement("div");
                 ccontent.className="box";
                 cparent.appendChild(ccontent);
                 var boximg=document.createElement("div");
                 boximg.className="box_img";
                 ccontent.appendChild(boximg);
                 var img=document.createElement("img");
                 img.src="images/"+imgData.data[i].src;
                 boximg.appendChild(img);
            } 
              imgLocation("container","box");
        }
      }
}

function checkFlag(){
      var cparent=document.getElementById("container");
      var ccontent=getChildnode(cparent,"box");
      var lastContentHeight=ccontent[ccontent.length-1].offsetTop;
      var scrollTop=document.documentElement.scrollTop||document.body.scrollTop;
      var pageHeight=document.documentElement.clientHeight||document.body.clientHeight;
      if (lastContentHeightreturn true;
      }
}
function imgLocation(parent,content){
         var cparent=document.getElementById(parent);
         var ccontent=getChildnode(cparent,content);
         var imgWidth=ccontent[0].offsetWidth;
         var cols=Math.floor(document.documentElement.clientWidth/imgWidth);
         cparent.style.cssText="width:"+imgWidth*cols+"px;margin:0 auto";

     //把第二排的左起第一张图片放到第一排高度最小的那张下面
         var imgHeightArr=[];
         for (var i = 0; i < ccontent.length; i++) {
                if (ielse{
                        var minHeight=Math.min.apply(null,imgHeightArr);
                        var minHeightIndex=getMinHeightLoc(imgHeightArr,minHeight);
                        console.log("minHeightIndex"+minHeightIndex);
            ccontent[i].style.position="absolute";
            ccontent[i].style.top=minHeight+"px";
            ccontent[i].style.left=ccontent[minHeightIndex].offsetLeft+"px";
            imgHeightArr[minHeightIndex]=imgHeightArr[minHeightIndex]+ccontent[i].offsetHeight;
                console.log(imgHeightArr[i]);
                console.log("高度最低:"+minHeight);
                }

       }

}

function getChildnode(parent,content){
     var contentArr=[];
     var allcontent=parent.getElementsByTagName("*");
   for (var i = 0; i < allcontent.length; i++) {
     if(allcontent[i].className==content){
           contentArr.push(allcontent[i]);
     }
   };

   return contentArr;
}

function getMinHeightLoc(imgHeightArr,minHeight){
      for(var i in imgHeightArr){
           if (imgHeightArr[i]==minHeight) {
              return i;
           }
      }
}

• 实现效果