var measures = new Array();
var values   = new Array();
var names    = new Array();
var namesng  = new Array();

measures[0]  = 'lb';
values[0]    = 453.592;
names[0]     = 'Pounds';
namesng[0]   = 'Pound';

measures[1]  = 'oz';
values[1]    = 28.3495;
names[1]     = 'Ounces';
namesng[1]   = 'Ounce';

measures[2]  = 'kg';
values[2]    = 1000;
names[2]     = 'Kilograms (kg)';
namesng[2]   = 'Kilogram (kg)';

measures[3]  = 'gr';
values[3]    = 1;
names[3]     = 'Grams (gr)';
namesng[3]   = 'Gram (gr)';

measures[4]  = 'mg';
values[4]    = 0.001;
names[4]     = 'Miligrams (mg)';
namesng[4]   = 'Miligram (mg)';

function convert(){
	var frm = document.getElementById("u_from");
	var to  = document.getElementById("u_to");
	var val = document.getElementById("m_from").value - 0;
	var resultbox = document.getElementById("result");	
	
	resultbox.innerHTML = '';
	
	if (frm.selectedIndex < 0){
		alert("Please select measure unit to convert from");
		frm.focus();
		return false;
	}
	
	if (to.selectedIndex < 0){
		alert("Please select measure unit to convert to");
		to.focus();
		return false;
	}
	
	var fromi = -1;
	var toi   = -1;
	for(var i=0; (fromi < 0 || toi < 0 )  && i < measures.length ; i++){
		if (measures[i] == frm.options[frm.selectedIndex].value){
			fromi = i;
		}
		if (measures[i] == to.options[to.selectedIndex].value){
			toi = i;
		}
	}
	
	if (fromi >= 0 && toi >= 0){
		var f1 = val * 	values[fromi];
		var t1 = f1 / values[toi];
		
		var rt = val + ' ' ;
		if (val == 1)
			rt += namesng[fromi];
		else
			rt += names[fromi];
		rt += ' = ' ;
		rt += t1 + ' ';
		if (t1 == 1)
			rt += namesng[toi];
		else
			rt += names[toi];
			
		resultbox.innerHTML = rt;
	}
	return false;
}