JavaScript函数不使用输入标记的onchange属性

sai*_*arm 0 html javascript internet-explorer google-chrome

我一直试图复制Duncan Donut示例HEAD FIRST JAVASCRIPT,但该函数subTotal()永远不会被onchange事件触发,当我查看HTML REFERENCE时,我没有在列表中找到任何onchange事件.

Duncan.html

    <html>
    <head><title>Duncan Online Donut's Service</title></head>
    <script type="text/javascript">

        function subTotal(){
            document.write("working");
            const TAXRATE = 0.095;
            const DONUTRATE = 0.5;
            var tax = 0;
            var subTotal = 0;
            var total = 0;
            var cakedonut = parseInt(document.getElementById("cakedonut").value);
            var glazedonut = parseInt(document.getElementById("glazedonut").value);

            if(isNaN(cakedonut))
                cakedonut = 0;
            if(isNaN(glazedonut))
                glazedounut = 0;

            subTotal = (cakedonut + glazedonut)* DONUTRATE ;
            tax = subTotal * TAXRATE ;
            total = subTotal + tax ;
            document.getElementById("subTotal").value = "$" + subTotal.toFixed(2);
            document.getElementById("tax").value = "$" + tax.toFixed(2);
            document.getElementById("total").value = "$" + total.toFixed(2);    
        }
    </script>
    <body>
        <h1><b><i>Duncan Online Donut's Service</i></b></h1>
        <form>
            Name : <input id="name" type="text" name="name"/><br><br>
            #no of cake donuts : <input id="cakedonut" type="text" name="cakedonut" onchange="subTotal()"/><br><br>
            #no of glazed donuts : <input id="glazedonut" type="text" name="glazedonut" onchange="subTotal("/><br><br>
            subTotal : <input id="subTotal" type="text" name="subTotal" /><br><br>
            tax : <input id="tax" type="text" name="tax" /><br><br>
            Total : <input id="total" type="text" name="total"/><br><br>
            <input type="submit"/><br><br>
        </form>
    </body>
</html>
Run Code Online (Sandbox Code Playgroud)

jsFiddle http://jsfiddle.net/o6vhzfcy/1/

以上是我的代码.我试过这个IE and Chrome但是徒劳无功.提前致谢.

Dip*_*ndu 6

问题是您已经定义了一个变量和一个具有相同名称subTotal的函数,并且变量声明覆盖了函数定义.将函数名称更改为任何说它将起作用的subTotal1.

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