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 verify_formemail(formfield) {
	if ((formfield.value == null) || (formfield.value == "") || isblank(formfield.value)) {
		alert("Der Inhalt von \"" + formfield.name + "\" ist keine email-Adresse!");
		formfield.focus();
		return true;
	} else {
		var substremail = formfield.value.split("@");
		if (substremail.length > 1)
  		{
			var index = substremail[1].indexOf(".");
			if (index == -1)
			{
				formfield.focus();
				alert("Der Inhalt von \"" + formfield.name + "\" ist keine email-Adresse!");
				return true;
			} else {
				return false;
			}
		} else {
			formfield.focus();
			alert("Der Inhalt von \"" + formfield.name + "\" ist keine email-Adresse!");
			return true;
		}	
	}
	return false;
}


function verify_formtext(formfield) {
	if ((formfield.value == null) || (formfield.value == "") || isblank(formfield.value)) {
		alert("Das Textfeld \"" + formfield.name + "\" darf nicht leer sein!");
		formfield.focus();
		return true;
	}
	return false;
}

function verify_formtextarea(formfield) {
	if ((formfield.value == null) || (formfield.value == "") || isblank(formfield.value)) {
		alert("Der Textbereich \"" + formfield.name + "\" darf nicht leer sein!");
		formfield.focus();
		return true;
	}
	return false;
}

function verify_formselect(formfield) {
	if ((formfield.value == null) || (formfield.value == "0")) {
		alert("Bitte selektieren Sie in der Auswahlbox \"" + formfield.name + "\" eine Option!");
		formfield.focus();
		return true;
	}	
	return false;
}