贴上代码HTML----------------------------------------------------------------<div id="tv_headline">监控画面<a onclick="changeshow();" href="javascript:void(0);" class="righttop" id="a1">以文本方式浏览</a></div>
<div id="tv"><img border="0" width="600" height="488" src="control/MakeImage.aspx" id="makeimage" usemap="#map" /></div>script---------------------------------------------------------------function changeshow(){
   if(showintext == 0){
       document.getElementById('tv').innerHTML = '<iframe src=about:blank width=600 height=488px frameborder=0 name=showmessageintext></iframe>';
       document.frames['showmessageintext'].location.href='text.html';
       document.getElementById('a1').innerText = '以图象方式浏览';
       showintext=1;
       }
    else{
       document.getElementById('tv').innerHTML = '<img src=control/MakeImage.aspx' width=600 height=488 border=0 id="makeimage" usemap=#Map>';
       document.getElementById('a1').innerText = '以文本方式浏览';
       showintext=0;
        }
}