function clear_select_options(selectbox)
{
	var _select = document.getElementById(selectbox);
	
	if(_select.length > 0)
	{
		while(_select.hasChildNodes())
		{
			for(var i = 0; i < _select.childNodes.length; i++)
			{
				_select.removeChild(_select.firstChild);
			}
		}
	}
}

function set_selected_index(selectbox, default_value)
{
	if(selectbox.value)
	{
		//Is Not a drop down box, just set value
		selectbox.value = trim(default_value);
		return true;
	}
	else if(selectbox.length)
	{
		if(selectbox.length > 0)
		{
			for(var i = 0; i < selectbox.length; i++)
			{
				if(selectbox.options[i].value == default_value)
				{
					selectbox.selectedIndex = i;
				}
			}
		}
		return true;
	}
	else
	{
		return false;
	}
}

function addSelectOption(selectbox,text,value)
{
	if(text.length > 0)
	{
		var elOptNew = document.createElement('option');
		elOptNew.text = text;
		elOptNew.value = value;
		var elSel = selectbox;
	
		try {
			elSel.add(elOptNew, null); // standards compliant; doesn't work in IE
		}
		catch(ex) {
			elSel.add(elOptNew); // IE only
		}
	}
}

function change_table_cell_data(cell_id, new_data)
{
	if(document.getElementById(cell_id))
	{
		document.getElementById(cell_id).innerHTML = new_data;
	}
}

function create_drop_down_box_html(drop_down_name, box_size, data_array)
{
	var new_text = '<select id="' + drop_down_name + '" name="' + drop_down_name + '" class="normalfont" ' + box_size + '>';
	
	for(var i = 0; i < data_array.length; i++)
	{
		new_text += '<option value="' + data_array[i][1] + '">' + data_array[i][0] + '</option>';
	}
	
	new_text += '</select>';
	return new_text;
}

function hide_div_layer(div_layer_id)
{
	if(document.layers)	   //NN4+
	{
		document.getElementById(div_layer_id).visibility = "hide";
	}
	else if(document.getElementById)	  //gecko(NN6) + IE 5+
	{
		document.getElementById(div_layer_id).style.visibility = "hidden";
	}
	else if(document.all)	// IE 4
	{
		 document.getElementById(div_layer_id).style.visibility = "hidden";
	}
}

function show_div_layer(div_layer_id)
{
	if(document.getElementById(div_layer_id).style.visibility == 'hidden')
	{
		if(document.layers)	   //NN4+
		{
			document.getElementById(div_layer_id).visibility = "show";
		}
		else if(document.getElementById)	  //gecko(NN6) + IE 5+
		{
			document.getElementById(div_layer_id).style.visibility = "visible";
		}
		else if(document.all)	// IE 4
		{
			 document.getElementById(div_layer_id).style.visibility = "visible";
		}
	}
}

function trim(str)
{
   return str.replace(/^\s*|\s*$/g,"");
}