function check_submit( myf )
{
	var x = "";
	var i;
	var xx_flag =1;
	var xx;

	//check email

	x += check_mail( myf.elements["E_mail"].value ,"Email address "+myf.elements["E_mail"].value);
	
	if( x== "" ) return true;
	else
	{
		alert(x);
		return false;
	}
}

function checkEmailFormat ( email )
{
   var len = email.length;
   var ck =0;
   if(len==0)
      return(-1);
   /*for(var i=0;i<len;i++)
   {  var c= email.charAt(i);
      if(!((c>="A"&&c<="Z")||(c>="a"&&c<="z")||(c>="0"&&c<="9")||(c=="-")||(c=="_")||(c==".")||(c=="@")))
         return (-3);
   }*/
   if((email.indexOf("@")==-1)||(email.indexOf("@")==0)||(email.indexOf("@")==(len-1)))
      return(-4);
   if((email.indexOf("@")!=-1)&&(email.substring(email.indexOf("@")+1,len).indexOf("@")!=-1))
      return(-4);
   //if((email.indexOf(".")==-1)||(email.indexOf(".")==0)||(email.lastIndexOf(".")==(len-1)))
   if((email.indexOf(".")==-1)||(email.lastIndexOf(".")==(len-1)))
      return(-5);
   return (0);
}

function check_mail( email , cname )
{
   var ck= checkEmailFormat(email);

   if(ck==-1)
   {
      return "Please input " + cname + " \n";
   }
   else if(ck==-3)
   {
      return cname + "琌计,璣ゅダの'-','_'单才腹,ㄤ才腹常ぃㄏノ !\n";
   }
   else if ((ck==-4) ||(ck==-5))
   {
      return cname + " illegal !\n";
   }
   
   return "";
}