<html> <head> <meta http-equiv="content-type" content="text/html" charset="UTF-8"> <script type="text/javascript" > var picArr=new Array("1.jpg","2.jpg","3.jpg") ; var index=0; //展示下一张图片 function next(){ index++; if (index==picArr.length){ index=0; } document.getElementById("img1").src=picArr[index]; } //展示上一张图片 function precious(){ index--; if (index<0){ index=picArr.length-1; } document.getElementById("img1").src=picArr[index]; } </script> <body> <img id="img1"src="1.jpg" width="500" height="300"/><br/> <input type="button" value="下一张" onclick="next()"/> <input type="button" value="上一张" onclick="precious()"/> <body> </html>