function email_check(form)
{  
  var check_at="false";
  var check_p="false";
  var checkOK = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-@ _ -.";
  var checkStr = form.value;
  var allValid = true;
  for (i = 0;  i < checkStr.length;  i++)
  {
    ch = checkStr.charAt(i);
    if (checkOK.indexOf(ch)==-1)
    {
       allValid = false ;
       break;
    }
	switch (ch)
	{
		case "@":check_at="true";
			 break;
		case ".":check_p="true";
		     break;
    }
  }
  if(check_p=="false" || check_at=="false")
  {
	alert("Please enter a valid email address.");
	form.focus();
	form.select();
  }	

  if (!allValid)
  {
    alert("Please enter only letter, digit and \"@ _ -.\" characters in the \"Email\" field.");
    form.focus();
    return (false);
  }
}  

function per_email_check(form)
{  
  var check_at="false";
  var check_p="false";
  var checkOK = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-@ _ -.";
  var checkStr = form.value;
  var allValid = true;
  for (i = 0;  i < checkStr.length;  i++)
  {
    ch = checkStr.charAt(i);
    if (checkOK.indexOf(ch)==-1)
    {
       allValid = false ;
       break;
    }
	switch (ch)
	{
		case "@":check_at="true";
			 break;
		case ".":check_p="true";
		     break;
    }
  }
  if(check_p=="false" || check_at=="false")
  {
	alert(" لطفا آدرس پست الكترونيكي معتبر وارد نماييد.	");
	form.focus();
	form.select();
  }	
  if (!allValid)
  {
    alert(" لطفا فقط حرف، رقم و @ و- و_ و . وارد نماييد. ");
    form.focus();
    return (false);
  }
} 

function check_string(form)
{
  var checkOK = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz ";
  var checkStr = form.value;
  var allValid = true;
  for (i = 0;  i < checkStr.length;  i++)
  {
    ch = checkStr.charAt(i);
    if (checkOK.indexOf(ch)==-1)
    {
       allValid = false ;
       break;
    }
  }
  if (!allValid)
  {
    alert("Please enter only letter. ");
    form.focus();
    return (false);
  }
}

function check_enstr(form)
{
  var checkOK = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz1234567890_";
  var checkStr = form.value;
  var allValid = true;
  for (i = 0;  i < checkStr.length;  i++)
  {
    ch = checkStr.charAt(i);
    if (checkOK.indexOf(ch)==-1)
    {
       allValid = false ;
       break;
    }
  }
  if (!allValid)
  {
    alert("       لطفا فقط حروف و اعداد و ـ وارد نماييد  ");
    form.focus();
    return (false);
  }
}
function check_number(form)
{
	var check="true";
	var value=form.value;
	var len=value.length;
	var i,n
	for (i=0; i<len; i++)
	{
		n=value.charAt(i)
		if (n != '1' && n != "2" && n != "3" && n != "4" && n != "5" && n != '6' && n != "7" && n != "8" && n != "9" && n != "0" && n != ".")
			check="false";
	}
	if (check=="false")
	{
		alert("Numbers only!");
		form.focus();
		form.select();
	}	
	return check;
}


function check_blank(form)
{
	var check="true";
	var value=form.value;
	var len=value.length;
	var i,n;
	for (i=0; i<len; i++)
	{
		if (value.charAt(i) == '"' || value.charAt(i) == "'")
			check="false";
	}
	if (check=="false")
	{
		alert("String Can't Contain Double Quote \" or single Quote \' ");
		form.focus();
		form.select();
		return check;
	}

	
	if (value=="")
	{
		check="false";
		alert("This Field can't be blank. ");
		form.focus();
		form.select();
		return check;
	}
	else
	{
		for (i=0; i<len; i++)
		{
			if (value.charAt(i) == '"' || value.charAt(i) == "'")
				check="false";
		}
		if (check=="false")
		{
			alert("String Can't Contain Double Quote \" or single Quote \' ");
			form.focus();
			form.select();
		}
		return check;
		}
}

function check_quote(form)
{
	var check="true";
	var value=form.value;
	var len=value.length;
	var i,n;
	for (i=0; i<len; i++)
	{
		if (value.charAt(i) == '"' || value.charAt(i) == "'")
			check="false";
	}
	if (check=="false")
	{
		alert("String Can't Contain Double Quote \" or single Quote \' ");
		form.focus();
		form.select();
		return check;
	}
}


function compare_elem(form1,form2)
{
  var check="true";
  var value1=form1.value;
  var value2=form2.value;
  if(value1!=value2)
	 {
	 check="false";
	 alert("You didn't confirm correctly.Try again!")
			 
	 }
	 return check;
}
		
function check_email(form)
{
  var check="true";
  var check_at="false";
  var check_p="false";
  var check_cama="true";
  var value=form.value;
  var len=value.length;
  var i=0,n="";
  while (i<len)
  {
	n=value.charAt(i);
	switch (n)
	{
		case "@":check_at="true";
				 break;
		case ".":check_p="true";
			     break;
		case ",":check_cama="false";
				 break;				
	}
    i++;				
  }	
  if(check_p=="false" || check_at=="false" || check_cama=="false")
  {
	check="false";
	alert("Please enter a valid email address.");
	form.focus();
	form.select();
  }	
  else
	check="true";
  return check;	
}