Question

我正在通过Beginning Javascript工作，但无法通过第2章完成练习2.练习是纠正这段代码

 <!DOCTYPE html>

<html lang="en">
<head>
    <title>Chapter 2, Finishing exercise 2</title>
</head>
<body>

    <script>
        var firstNumber = prompt("Enter the first number", "");
        var secondNumber = prompt("Enter the second number", "");
        var theTotal = firstNumber + secondNumber;

        document.write(firstNumber + " added to " + secondNumber + " equals " theTotal);

    </script>
</body>
</html>

我可以使用提醒显示正确的总数，但是当我删除评论时，它不再有效。

<!DOCTYPE html>

<html lang="en">
<head>
    <title>Chapter 2, Finishing exercise 2</title>
</head>
<body>
    <script>
        var firstNumber = prompt("Enter the first number", "");
        var secondNumber = prompt("Enter the second number", "");


        var intFirstNumber = parseInt(firstNumber, 10);
        var intSecondNumber = parseInt(secondNumber, 10);
        var theTotal = intFirstNumber + intSecondNumber;


        alert(theTotal);
        //document.write (intFirstNumber + " added to " + intSecondNumber + " equals " theTotal);

    </script>
</body>
</html>

我无法弄清楚我的document.write语句是错误的。任何提示？另外还有更优雅的方式来实现我正在做的事情吗？

Answer 1

namespace std和+：

之间需要另一个"equals"

theTotal

在这种情况下，document.write(firstNumber + " added to " + secondNumber + " equals " + theTotal);符号意味着连接（追加）之后的任何内容，以及之前发生的任何内容。

进一步阅读：

MDN documentation for string concatenation

开始Javascript第2章完成练习2

1 个答案: