function checkStringInput (control, valname)
{
	if (control.value == "") {
		window.alert ("Please, enter a value for " + valname);
		control.focus();
		return false;
	}
	return true;
}

function checkNumericInput (control, valname)
{
	if (control.value == "") {
		window.alert ("Please, enter a value for " + valname);
		control.focus();
		return false;
	}
	if (isNaN(parseFloat (control.value))) {
		window.alert ("Please, enter a valid value for " + valname);
		control.value = "";
		control.focus();
		return false;
	}
	return true;
}

function checkIntInput (control, valname)
{
	if (control.value == "") {
		window.alert ("Please, enter a value for " + valname);
		control.focus();
		return false;
	}
	if (isNaN(parseInt (control.value))) {
		window.alert ("Please, enter a valid value for " + valname);
		control.value = "";
		control.focus();
		return false;
	}
	return true;
}

function checkEmailInput (control, valname) {
	if (control.value == "") {
		window.alert ("Please, enter a value for " + valname);
		control.focus();
		return false;
	}
	if (control.value.indexOf("@") == -1) {
		window.alert ("Please, enter a valid value for " + valname);
		control.value = "";
		control.focus();
		return false;
	}
	return true;
}