JavaScript

超轻量级php框架startmvc

JavaScript实现的DOM绘制柱状图效果示例

更新时间:2020-07-20 00:42:01 作者:startmvc
本文实例讲述了JavaScript实现的DOM绘制柱状图效果。分享给大家供大家参考,具体如下:<!

本文实例讲述了JavaScript实现的DOM绘制柱状图效果。分享给大家供大家参考,具体如下:


<!DOCTYPE html>
<html>
 <head>
 <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
 <title>www.jb51.net JavaScript DOM绘制柱状图</title>
 <style>
 #chart-wrap{ 
 width:910px; 
 height:240px;
 border:solid 1px #B3B3DC;
 position:relative; 
 top:40px; 
 left:20px;
 } 
 </style>
 </head>
 <body>
 <div id="chart-wrap"></div>
 <script>
 function renderChart(data) {
 var cw = document.getElementById("chart-wrap"); 
 cw.innerHTML = ""; 
 var max = 0; 
 for (var index in data) {
 if (data[index] > max)
 max = data[index];
 }
 var percent = 180 / max; 
 var i = 0;
 for (var index in data) { 
 var bar = document.createElement("div"); 
 bar.id = index + "_" + data[index]; 
 bar.style.height = Math.round(percent * data[index]) + "px"; 
 bar.style.width = "40px";
 bar.style.left = (i * 40) + 165 + "px"; 
 bar.style.marginLeft = (i * 20) + "px"; 
 bar.style.position = "absolute"; 
 bar.style.background = "none repeat scroll 0 0 pink";
 bar.style.overflow = "hidden";
 bar.setAttribute("title", index + ":" + data[index]);
 bar.style.display = "block"; 
 bar.style.top = 200 - Math.round(percent * data[index]) + "px"; 
 cw.appendChild(bar); 
 var axis = document.createElement("div"); 
 axis.id = "axis_" + i; 
 axis.style.width = "40px"; 
 axis.style.left = (i * 40) + 165 + "px"; 
 axis.style.marginLeft = (i * 20) + "px";
 axis.style.textAlign = "center"; 
 axis.style.position = "absolute"; 
 axis.style.top = "205px"; 
 axis.innerHTML = '<span style="font-size:12px; color:grey;"> ' + i + '</span>'; 
 cw.appendChild(axis); 
 i++;
 } 
 for (var i = 0; i < 5; i++) { 
 var ayis = document.createElement("div"); 
 ayis.style.width = "30px"; 
 ayis.style.position = "absolute"; 
 ayis.style.top = (36 * i) + (20 - 6) + "px"; 
 ayis.style.left = "140px"; 
 ayis.innerHTML = '<span style="font-size:12px; color:grey;"> ' + Math.round(max - (max / 5) * i) + '</span>'; 
 cw.appendChild(ayis); 
 var line = document.createElement("div"); 
 line.setAttribute("style", "width:580px; left:165px; border-top:1px dotted grey; height:1px; line-height:1px; display:block; overflow:hidden; position:absolute; "); 
 line.style.top = (36 * i) + 20 + "px"; 
 cw.appendChild(line); 
 } 
 }
 var data = [10,60,50,30,40,80,20,70,100,90];
 renderChart(data);
 </script>
 </body>
</html>

运行效果如下:

JavaScript DOM 绘制柱状图