function trim(txt_value)
{
	return (txt_value.replace(/^\s|\s*$/g,""));
}


function validateEmail(elementValue)
{   
   var emailPattern = /^[a-zA-Z0-9._-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,4}$/;   
   return emailPattern.test(elementValue);   
}  



function validatephone(var_value)
{
	count=0;
	for(var i=0;i<var_value.length;i++)
	{
		if((var_value.charAt(i)>='a' && var_value.charAt(i)<='z') || (var_value.charAt(i)>='A' && var_value.charAt(i)<='Z'))
		{
			return false;
		}
	}
	return true;
}


function validate_contact_form()
{
	if (trim(document.contact_form.txt_name.value)=="")
	{
		alert("Please enter your name.");
		document.contact_form.txt_name.focus();
		return false;
	}
	else if(trim(document.contact_form.txt_email_address.value)=="")
	{
		alert("Please enter your email.");
		document.contact_form.txt_email_address.focus();
		return false;		
	} 
	else if(!validateEmail(trim(document.contact_form.txt_email_address.value)))
	{
		alert("Please enter your valid email.");
		document.contact_form.txt_email_address.focus();
		return false;		
	}
	else if(trim(document.contact_form.txt_phone.value)=="")
	{
		alert("Please enter telephone number.");
		document.contact_form.txt_phone.focus();
		return false;		
	}
	else if(!validatephone(trim(document.contact_form.txt_phone.value)))
	{
		alert("Please enter valid telephone number.");
		document.contact_form.txt_phone.focus();
		return false;		
	}
	else if(trim(document.contact_form.txt_area_message.value)=="")
	{
		alert("Please enter message.");
		document.contact_form.txt_area_message.focus();
		return false;		
	} 
	 
	else
	{
		return true;
	}
}