document.write('<a href="http://passport.youyouchina.com/reg">用户注册</a><a href="http://passport.youyouchina.com/lostpwd">忘记密码</a><form name="form_login" id="form_login"  enctype="application/x-www-form-urlencoded" action="http://passport.youyouchina.com/chklogin/" method="post" onsubmit="return loginchk(this);"><input type="hidden" name="fromurl" id="top_fromurl" value=""><label>用户名：</label><input type="text" name="username" id="l_username" /><label>密码：</label><input type="password" name="userpass" id="l_userpass" /><input type="image" src="http://images.youyouchina.com/public/0804/login.jpg" /></form><script type="text/javascript">document.getElementById("top_fromurl").value=document.location;function loginchk(formobj){var username = $("l_username").value.trim();var userpass = $("l_userpass").value.trim();if(strLen(username)<4 || strLen(username) >16){alert("请输入正确的用户名");return false;}if(strLen(userpass)<6 || strLen(userpass)>16){alert("请输入正确的密码");return false;}}</script>');