document.write ("<Script"+" ID='lgSubFrm' src=''></"+"script>");

  function UserLogon(){
     if (lgFrm.user.value.length<1 || lgFrm.user.value=="留学网用户ID"){alert("请填写正确的用户名");lgFrm.user.focus();return false;}
     if (lgFrm.Password.value.length<1){alert("请输入正确密码!");lgFrm.Password.focus();return false;}
     if (!clStr(lgFrm.user.value,"1234567890abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_")){alert("用户名中只能使用数字,英文及下划线,\n\r如果你注册中使用了其它字符或中文,请与管理员联系!");lgFrm.user.focus();return false;}
     if (lgFrm.logonType.value=='1'){
        lgFrm.action="http://www.liuxue.net:3000/WorldClient.dll?View=Main";
        lgFrm.target="_top";
        lgFrm.submit();
     }
     else {
       if (lgFrm.logonType.value=='0'){
        var tempTime=new Date();
        lgSubFrm.src="http://www.liuxue.net/serve/logon2004.asp?UserName="+lgFrm.user.value+"&pwd="+lgFrm.Password.value+"&Id="+tempTime;
       }
     }
  }
  function clStr(sStr,cStr){              //检测字符串sStr的字符,是否在cStr中,如全部都在返回true,否则返回false;
    for (var i=0;i<sStr.length;i++){
        var tempstr=sStr.substring(i,i+1);
        if (cStr.indexOf(tempstr,0)==-1) return false;
    } 
    return true;
  }
  document.write ("<form name=\"lgFrm\" action=\"\" method=\"post\">");
  document.write ("<td style=\"padding-left:4px;padding-right:4px\" align=\"center\" valign=\"middle\">");
  document.write ("  用户名:<input type=\"text\" name=\"user\" style=\"width:80\" value=\"留学网用户ID\" class=\"s01\" onfocus=\"javascript:this.value='';\">");
  document.write ("  密码:<input type=\"password\" name=\"Password\" style=\"width:80\" value=\"**********\" class=\"s01\" onfocus=\"javascript:this.value='';\">");
  document.write ("  <select name=\"logonType\" style=\"font-size:9pt;background-color:#F4F4F4\">");
  document.write ("    <option value=\"0\" selected>留学会员</option>");
  document.write ("    <option value=\"1\">免费邮箱</option>");
  document.write ("  </select>");
  document.write ("  <img type=\"image\" src=\"http://www.liuxue.net/images/submit.gif\" align=\"absmiddle\"  style=\"cursor:hand\" onclick=\"javascript:UserLogon();\">");
  document.write ("  <a href=\"http://www.liuxue.net/serve/reg.asp\" target=\"_top\"><img src=\"http://www.liuxue.net/images/login2.gif\" align=\"absmiddle\" border=\"0\"></a>");
  document.write ("</td>");
  document.write ("</form>");