我正在学习初级Javascript,但无法通过第二章完成练习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alert获得正确的总数,但是当我删除注释时,它不再工作。
<!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>
我不知道我的文件怎么办。写的陈述是错误的。有提示吗?此外,是否有更优雅的方式来实现我正在做的事情?
在"equals"
和theTotal
之间需要另一个+
:
document.write(firstNumber + " added to " + secondNumber + " equals " + theTotal);
在此上下文中,+
符号表示将它后面的内容连接(追加)到它前面的内容。
进一步阅读:
字符串连接的MDN文档。