Javascript代码不起作用

Question

我的JavaScript代码不工作，它应该计算午餐菜单项的总价格并给出总结果，但是没有任何结果。该html工作正常，所以我只是在这里写javascript部分，它很短。我从字面上遵循指示来获得这段代码，所以我没有得到什么错误。谢谢:)

function calcTotal() 
{ 
    var itemTotal=0; 
    var items=document.getElementsByTagName("input"); 
    //collects them into a NodeList object, which has indices 

    for(var i=0;i<5;i++) 
    { 
     if(items[i].checked) 
     itemTotal+=(items[i].value*1); //the *1 turns it into a number 
    } 
    document.getElementById("total").innerHTML="Your order total is $"+itemTotal + ".00"; 
    var submitButton = document.getElementById("sButton"); 
    if(submitButton.addEventListener) 
    { 
     submitButton.addEventListener("click",calcTotal,false); 
    } 

    else if(submitButton.attachEvent) 
    { 
     submitButton.attachEvent("onclick", calcTotal); 
    } 
} 

Answer 1

好了，我们需要看到的HTML，但乍看之下，我会说这是因为您要设置事件的回调将不会被调用内部的事件绑定除非你设置了事件绑定。你必须设置那些拳头：

// First set up the event handling 
var submitButton = document.getElementById("sButton"); 

// In this case, you can just check window to see if it has the property 
if(window.addEventListener) { 
    submitButton.addEventListener("click",calcTotal,false); 
} else if(window.attachEvent) { 
    submitButton.attachEvent("onclick", calcTotal); 
} 

// And, have the callback separate 
function calcTotal() { 
    var itemTotal=0; 
    var items=document.getElementsByTagName("input"); 
    //collects them into a NodeList object, which has indices 

    for(var i=0;i<5;i++) { 
     if(items[i].checked) 
     itemTotal+=(items[i].value*1); //the *1 turns it into a number 
    } 

    document.getElementById("total").innerHTML="Your order total is $"+itemTotal + ".00"; 
}