function addByValue(elementId, optionValue, optionText) {                        
    var el = document.getElementById(elementId);
       
    newoption = new Option(optionText, optionValue, false, false);
    el.options[el.length] = newoption;
}


function removeByValue(elementId, value) {
    var el = document.getElementById(elementId);

    for (var x = 0; x < el.length; x++) {
        if (el.options[x].value == value) {
        	el.options[x] = null;
        	break;
        }
    }
}


function setSelectedValue(elementId, value) {
    var el = document.getElementById(elementId);
    
    for(var i = 0; i < el.length; i++) {
		if (el.options[i].value == value) {
			el.selectedIndex = i;
			break;
		}
	}
} 


function getSelectedValue(elementId) {
	var el = document.getElementById(elementId);
	
	return el.options[el.selectedIndex].value;
}


function removeAllOptions(elementId) {
    var el = document.getElementById(elementId);
    
    for (x = el.length; x >= 0; x--) {
        el.options[x] = null;
    }
}


function getRadioValue(elementName) {
	el = document.getElementsByName(elementName);

	for(var i = 0; i < el.length; i++) {
		if(el[i].checked)
			return el[i].value;
	}
}


function getCheckBoxList(elementName) {
    var el = document.getElementsByName(elementName);
    var o = [];

	for(var i = 0; i < el.length; i++) {
		if(el[i].checked) {
			o.push(el[i].value);
		}
	}
	
	return o.join(',');
}