// VARIABLE DECLARATIONS
var digits = "0123456789";
var lowercaseLetters = "abcdefghijklmnopqrstuvwxyz"
var uppercaseLetters = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
// whitespace characters
var whitespace = " \t\n\r";

		function validate_required(field,alerttxt)
		{
		    with (field)
		    {
			if (isWhitespace (field))
  			{
				alert(alerttxt);
				field.focus();
				return false;
			} else {return true}
		    }
		}


		function validate_form(thisform)
		{
		    with (thisform)
		    {			
			if (!validate_required(Name, "Name is required!")) return false;
  			if (!validate_required(Company, "Company is required!")) return false;
  			if (!validate_required(Telephone, "Telephone is required!")) return false;
			if (!validate_required(Email, 'Email is required!')) return false;
			if (!validateEmail(Email, 'Email is invalid!')) return false;
								
		     }
		     return true;
		}

		function validateEmail  (field,alerttxt)   
		{ 			
  			//var email = /^[^@]+@[^@.]+\.[^@]*\w\w$/
			var email = /^[a-zA-Z][\w\.-]*[a-zA-Z0-9]@[a-zA-Z0-9][\w\.-]*[a-zA-Z0-9]\.[a-zA-Z][a-zA-Z\.]*[a-zA-Z]$/
  			if (!email.test(field.value)) {
    				alert(alerttxt);
				field.focus();
				field.select();
				return false;		
  			}else  {return true;}			
		};	

		// Returns true if string s is empty or whitespace characters only.
		function isWhitespace (s)
		{   var i;
    		    if (s==null || s.value.length == 0) return true;	
			
		   for (i=0; i< s.value.length; i++)
    		    {  			
        		var c = s.value.charAt(i);
			if (whitespace.indexOf(c) == -1) return false;
    		    }
    		    return true;
		}