<!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=utf-8" /><title>無(wú)標(biāo)題文檔</title></head><body>????<center>????????<form>????????????name<input type="text" id='name'/>????????????<br />????????????key ? ?<input type="text" id='key'/>????????????<br />????????????<br />????????????<input type="button" value="submit" id='sub' onclick="check()"/>????????????<input type="reset" value="clear" id='clr'/>????????</form></center><script type="text/javascript">var name=document.getElementById('name');var key=document.getElementById('key');function check(){ if (name.value==""){ alert("please input your name!"); } if (key.value==""){ alert("input your key!"); } }</script></body></html>
這段代碼為什么name為空不彈出
慕用9244143
2017-04-02 11:45:03
