jquery $ 提交 onclick

js

<!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>无标题文档</title>
<script  language="javascript">
function $(id)
{
return document.getElementById(id);
}
function getvalue(obj)
{ var m=$(obj).value;
   alert(m);  
}
</script>
</head>

<body><input name="textfield" type="text" id="textfield" />
<input type="submit" name="button" id="button" value="提交"  onclick="getvalue('textfield')"/>

</body>
</html>