function isblank(s)
{
    for(var i = 0; i < s.length; i++) {
        var c = s.charAt(i);
        if ((c != ' ') && (c != '\n') && (c != '\t')) return false;
    }
    return true;
}
function isValidEmail(e)
{
	exp="^[a-zA-Z0-9._-]+@[a-zA-Z0-9-]+\.[a-zA-Z]{2,4}(\.[a-zA-Z]{2,3})?(\.[a-zA-Z]{2,3})?$";
	emailregexp = new RegExp(exp);
	result = e.match(emailregexp);
	if (result != null)
	{
		return true;
	}
	else
	{
		return false;
	}
}

function isValidNumber(numval)
{
	if (numval==""){return false;}
	var myRegExp = new RegExp("^[+()/#*-_]?[0-9]?[+()/#*-_]*[/.]?[0-9]*$");
	return myRegExp.test(numval);
}

function CheckExtension(fld)
{
    if (valid_extensions.test(fld.value)) return true;
    alert('The selected file is of the wrong type.');
    fld.select();
    fld.focus();
    return false;
}