var msg='' var msgi; function scroll(objid) { var obj=document.getElementById(objid); var tmp=(obj.scrollLeft)++; if(obj.scrollLeft==tmp) { msgi++; obj.innerHTML=msgi==20?msg:obj.innerHTML + msg;//防止内容越积越多 } } document.write('
'); document.write(msg); document.write('
'); setInterval("scroll('announce')",30);