无法取消选中复选框(HTML)

Question

我正在使用javaScript为表单上的自动完成函数，并在我的HTML文件中遇到了复选框的问题。基本想法是，用户应该能够在表单fieldset中填写其运输名称和邮政编码，然后如果他们签出"计费信息相同？"，则将称为填充计费的JS函数具有相同运输值的计费名称和邮政编码的现场集。复选框能够完成此操作，但我无法取消选中的方式清除计费信息。本质上，我无法取消选中我的复选框。我的代码如下：

function billingFunction(){
  var billName=document.getElementById("billingName");
  var shipName=document.getElementById("shippingName");
  var billZip=document.getElementById("billingZip");
  var shipZip=document.getElementById("shippingZip");
  var same=document.getElementById("same");
  if (same.checked=true){
    billName.value=shipName.value;
    billZip.value=shipZip.value;
  }
  else{
    billName.value="";
    billZip.value="";
  }
}

<form>
    <fieldset>
        <legend>Shipping Information</legend>
        <label for ="shippingName">Name:</label>
        <input type = "text" name = "shipName" id = "shippingName" required><br/>
        <label for = "shippingZip">Zip code:</label>
        <input type = "text" name = "shipZip" id = "shippingZip" pattern = "[0-9]{5}" required><br/>
    </fieldset>
    <input type="checkbox" id="same" name="same" onchange= "billingFunction()"/>
    <label for = "same">Is the Billing Information the Same?</label>
    <fieldset> 
        <legend>Billing Information</legend>
        <label for ="billingName">Name:</label>
        <input type = "text" name = "billName" id = "billingName" required><br/>
        <label for = "billingZip">Zip code:</label>
        <input type = "text" name = "billZip" id = "billingZip" pattern = "[0-9]{5}" required><br/>
    </fieldset>
        <input type = "submit" value = "Verify"/>
    </form>

Answer 1

您的if语句比较没有使用正确的平等检查，而是将检查属性分配为true。从：

更改您的代码

if (same.checked=true){ //This does assignment
   billName.value=shipName.value;
   billZip.value=shipZip.value;
}
else{
   billName.value="";
   billZip.value="";
}

：

if (same.checked === true){ //This does equality check
   billName.value=shipName.value;
   billZip.value=shipZip.value;
}
else{
   billName.value="";
   billZip.value="";
}

Answer 2

您将值分配给相同。修改：if(same.checked == true(或简单地if(same.checked(