function calculate()
{	
    var careaIndex=document.formmaths.carea.selectedIndex;
	if (careaIndex==0)
	{
	    alert("請下拉選擇取件公司的區域!"); 
		document.formmaths.carea.focus();
		return false;
	}  
   var dareaIndex=document.formmaths.darea.selectedIndex;
	if (dareaIndex==0)
	{
	    alert("請下拉選擇送件公司的區域!"); 
		document.formmaths.darea.focus();
		return false;
	}  
    var amount=document.formmaths.amount.value;
	if (amount<=0)
	{
		alert("件數不能小于零！");
		document.formmaths.amount.focus();
		document.formmaths.amount.select();
		return false;
	}
	var weight=document.formmaths.weight.value;
	if (weight<0)
	{
		alert("重量要大于零！");
		document.formmaths.weight.focus();
		document.formmaths.weight.select();
		return false;
	}
	return true;
}
function ecalculate()
{	
    var careaIndex=document.formmaths.carea.selectedIndex;
	if (careaIndex==0)
	{
	    alert("請下拉選擇取件公司的區域!"); 
		document.formmaths.carea.focus();
		return false;
	}  
   var dareaIndex=document.formmaths.darea.selectedIndex;
	if (dareaIndex==0)
	{
	    alert("請下拉選擇送件公司的區域!"); 
		document.formmaths.darea.focus();
		return false;
	}  
    var amount=document.formmaths.amount.value;
	if (amount<=0)
	{
		alert("件數不能小于零！");
		document.formmaths.amount.focus();
		document.formmaths.amount.select();
		return false;
	}
	var weight=document.formmaths.weight.value;
	if (weight<0)
	{
		alert("重量要大于零！");
		document.formmaths.weight.focus();
		document.formmaths.weight.select();
		return false;
	}
	return true;
}