本节内容：
js进度条效果的实现方法
一，js进度条方法一:
Loading.js
//频率
var frequency = 50;
//步长
var step = 3;
//背景颜色
var loadingBgcolor = "#ffffff";
//宽度
var loadingWidth = 354;
/*
*参数说明:
*content：显示内容，可以为空；
*imageURL：将引用JS文件的路径设置即可；
*left：进度条显示位置left
*top：进度条显示位置top
*/
function Loading(content, imageURL, left, top)
{
imageURL = imageURL + "Loading.jpg";
LoadTable(content, imageURL, left, top);
showimage.style.display="";
window.setInterval("RefAct();", frequency);
}
function RefAct()
{
imgAct.width += step;
if(imgAct.width > loadingWidth-4)
{
imgAct.width = 0;
}
}
function LoadTable(content, imageURL, left, top)
{
var strLoading;
strLoading = "";
strLoading += "<div id="showimage" style="DISPLAY:none;Z-INDEX:100;LEFT:" + left+ "px;POSITION:absolute;TOP:" + top+ "px;" align="center">";
strLoading += "<TABLE id="Table1" cellSpacing="0" cellPadding="0" width="" + loadingWidth + "" border="0" bgcolor="" + loadingBgcolor+ "">";
if(content != "")
{
strLoading += "<tr>";
strLoading += "<td align="center">";
strLoading += "<font size="4" face="Courier New, Courier, mono"><strong>" + content + "</strong></font>";
strLoading += "</td>";
strLoading += "</tr>";
strLoading += "<TR>";
}
strLoading += "<TD class="Loading" height="8">";
strLoading += "<IMG id="imgAct" height="8" alt="" src="" + imageURL + "" width="0">";
strLoading += "</TD>";
strLoading += "</TR>";
strLoading += "</TABLE>";
strLoading += "</div>";
document.getElementById("loading_div").innerHTML = strLoading;
}
使用页：
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>Untitled Document</title>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<script src="LoadingJS/Loading.js" type="text/javascript"></script>
</head>
<body>
<input type="button" name="Button" value="Button" onclick="Loading('显示标签内容', 'LoadingJS/', 20, 100)">
<div id="loading_div" ></div>
</body>
</html>
二，js进度条方法2：
js实现进度显示功能
progress.js类文件：
$ = function (id) {
return document.getElementById(id);
}
//文本转JSON字符串
String.prototype.toJson = function () {
if (this == ) {
return null;
}
else {
try {
return eval(( + this.replace(/rn/g, rn) + ));
}
catch (err) {
}
}
};
//字符格式化方法
String.prototype.format = function () {
var newStr = this;
var reg = null;
for (var i = 0; i < arguments.length; i++) {
reg = RegExp('{' + (i) + '}', 'gm');
newStr = newStr.replace(reg, arguments[i]);
}
return newStr;
};
//进度条类
function Progress(objId) {
//window.setInterval对象
this.interval = null;
//进度条对象ID
this.id = objId;
//当前进度 起始进度为0
this.progress = 0;
//进度条显示进度的DIV ID
this.progressId = inner + this.id;
//进度条边框ID
this.progressFrameId = frame + this.id;
//进度条类参数配置
this.config = {
//宽度
width: 150,
//高度
height: 20,
//左边距
left: 0,
//顶部边距
top: 0,
//进度颜色
progressColor: red,
//边框颜色
borderColor: #ccc,
//边框宽度
borderHeight: 2,
//进度完成后间隔N秒后隐藏进度条 0为立即隐藏
hiddenSplit:2000
};
}
//进度条类初始化方法
Progress.prototype.init = function () {
//新建进度条边框DIV
var progressdiv = document.createElement(div);
//边框DIV样式
var progressdiv_css_text = position:absolute;width:{0}px;height:{1}px;left:{2}px;top:{3}px;border:{4} {5}px solid;.format
(
this.config.width,
this.config.height,
this.config.left,
this.config.top,
this.config.borderColor,
this.config.borderHeight
);
//重置进度为0
this.progress = 0;
//设置边框ID
progressdiv.id = this.progressFrameId;
//设置边框样式
progressdiv.style.cssText = progressdiv_css_text;
//设置进度条HTML
progressdiv.innerHTML = '
'.format(this.progressId, this.config.height, this.config.progressColor);
//加入body中
document.body.appendChild(progressdiv);
};
//进度条隐藏函数
Progress.prototype.hiddenProgress = function () {
document.body.removeChild(document.getElementById(this.progressFrameId));
window.clearInterval(this.interval);
}
//进度结束时触发的函数
Progress.prototype.complete = function () {
window.clearInterval(this.interval);
this.interval = window.setTimeout(this.id+.hiddenProgress();,this.config.hiddenSplit);
if (this.completeCallBack) {
this.completeCallBack();
}
}
//进度每次运行后的回调函数
Progress.prototype.callback = function () {
var progressDiv = document.getElementById(this.progressId);
var progressFrameDiv = document.getElementById(this.progressFrameId);
progressDiv.innerHTML = (this.progress*100)+ %;
progressFrameDiv.title = 上传进度: + (this.progress*100) + %;
progressDiv.style.width = (this.progress*100) + %;
if (this.progress >= 1) {
this.complete();
progressDiv.innerHTML = 文件上传成功!;
}
}
//进度条运行函数。需要用户自己实现
Progress.prototype.run = function () {
alert(请实现 + this.id + .run方法以实现异步进度请求，回发回请调回调 + this.id + .callback方法。);
window.clearInterval(this.interval);
}
//启动进度
Progress.prototype.start = function () {
this.init();
this.interval = window.setInterval(this.id + .run(), 1000);
}
2）、图片加载进度实时显示进度条：