window.setInterval("Time()",1);

    	function Time()

		{

			var date = new Date();//当前时间函数

			var n = date.getFullYear();//年

			var y = date.getMonth()+1;//月注意+1

			var r = date.getDate();//日

			var x = date.getHours();//时

			var f = date.getMinutes();//分

			var m = date.getSeconds();//秒

			var h = date.getMilliseconds() //获取毫秒

			var str = "当前时间："+n+"年"+y+"月"+r+"日"+x+":"+f+":"+m+":"+h;//字符串拼接

			document.getElementById("date").innerHTML = str;//效果和/*date=document.getElementById("date");
                        date.innerHTML = str*/一样

		}

    <head>

        <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />

        <title>无标题文档</title>

        <style type="text/css">

        	*{

				margin:0px auto;

				padding:0px;

				}

			#wai{

				width:500px;

				height:500px;

				}

			#zuo{

				float:left;

				width:200px;

				height:500px;

				}

			#zhong{

				float:left;

				width:100px;

				height:500px;

				}

			#you{

				float:left;

				width:200px;

				height:500px;

				}

        </style>

    </head>

    <body>

        <div id="wai">

        	<div id="zuo">

            	<select multiple="multiple" id="znr" style="width:200px; height:200px;">

                	<option value="山东">山东</option>

                    <option value="淄博">淄博</option>

                    <option value="张店">张店</option>

                </select>

            </div>

            <div id="zhong">

            	<div style="margin-left:25px; margin-top:20px;"><input type="button" value=">>" style="width:50px;"  /></div>

                <div style="margin-left:25px; margin-top:20px;"><input type="button" value=">" style="width:50px;" /></div>

            </div>

            <div id="you">

            	<select id="ynr" multiple="multiple" style="width:200px; height:200px;">

                </select>

            </div>

        </div>

    </body>

<div style="margin-left:25px; margin-top:20px;"><input type="button" value=">>" style="width:50px;" onclick="Moveall()" /></div>

<div style="margin-left:25px; margin-top:20px;"><input type="button" value=">" style="width:50px;" onclick="Moveone()"/></div>

		function Moveone()

		{

			var left = document.getElementById("znr");//获取id的元素

			var right = document.getElementById("ynr");

			var lz = left.value;//获取value属性

			var str;//定义变量

			str ="<option value='"+lz+"'>"+lz+"</option>";//字符串拼接

			var bs=0;//随便设置

			for(var i=0;i<right.childNodes.length;i++)

			{

				if(right.childNodes.item(i).text == lz)

				//right.childNodes.item(i).text=select下子元素里每个索引对应的文本

				{

					bs = 1;//只要不等于0就行

				}

			}

			if(bs==0)

			{

				right.innerHTML = right.innerHTML+str;//

			}

		}

		function Moveall()

		{

			var left = document.getElementById("znr");

			var right = document.getElementById("ynr");

			right.innerHTML = left.innerHTML;

		}