帮忙看一下js的进度条代码

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<title>无标题文档</title>
<html>
<head><SCRIPT type="text/javascript">
       var id;
   function begin(){
   var bar;
   var bar2=10;
   var i=1;
    function get(){ if(i%2==1){
bar="亲爱的读者";
}else{
bar="你们好";
}
i++;
document.getElementById("bar").innertext=bar;
if(document.getElementById("bar2").style.width=bar2+"px"){
bar2=10;
}else{
bar2+=5;
}
document.getElementByid("bar2").style.width=bar2+"px";
}
id=setinterval(get,1000);
}</SCRIPT> 
<style type="text/css">
#bar2{width:10px;
height:20px;
background:#ccc;
}
</style>
</head>
<body><hr/>
<button onclick="begin();">开始</button>
<div id="bar2"></div></body>
</html>
我实在是  搞不懂 哪里 错了...刚开始 学习js 看着书 写代码 没一个能运行了...我就服了///.

解决方案 »

  1.   

    <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
    <html xmlns="http://www.w3.org/1999/xhtml">
    <head>
    <meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
    <title>无标题文档</title>
    <html>
    <head> 
    <style type="text/css">
    #bar2{width:10px;
    height:20px;
    background:#ccc;
    }
    </style>
    </head>
    <body><hr/>
    <button onclick="begin()">开始</button>
    <div id="bar2" style="width:10px;"></div>
    <SCRIPT type="text/javascript">
      var id;
      var bar;
    var bar2=10;
    var i=1;
    function begin(){


    id=setInterval('_get()',1000);
    }function _get(){
    if(i%2==1){
    bar="亲爱的读者";
    }else{
    bar="你们好";
    }
    i++;
    document.getElementById("bar2").innerHTML=bar;
    if(document.getElementById("bar2").style.width=bar2+"px"){
    bar2=10;
    }else{
    bar2+=5;
    }
    document.getElementById("bar2").style.width=bar2+"px";
    }</SCRIPT> 
    </body>
    </html>
      

  2.   

    <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
    <head><SCRIPT type="text/javascript">
        var id;
        function begin() {
            var bar;
            var bar2 = 10;
            var i = 1;
            function get() {            if (i % 2 == 1) {
                    bar = "亲爱的读者";
                } else {
                    bar = "你们好";
                }
                i++;
                document.getElementById("bar2").innerHTML = bar;
                if (document.getElementById("bar2").style.width = bar2 + "px") {
                    bar2 = 10;
                } else {
                    bar2 += 5;
                }
                document.getElementById("bar2").style.width = bar2 + "px";
            }
            return setInterval(get, 1000);
        }</SCRIPT>  
    <style type="text/css">
    #bar2{width:10px;
    height:20px;
    background:#ccc;
    }
    </style>
    </head>
    <body><button onclick="begin();">开始</button>
    <div id="bar2"></div></body>
    </html>
    一堆错误。。难道你都不自己运行的吗？！
      

  3.   

     if (document.getElementById("bar2").style.width = bar2 + "px") {
      这个判断实现看不懂什么意思！！！   还有取当前运行的样式要用 iE用currentStyle  firxfox window.getComputedStyle(div,null).width; //return   300px