Question

我目前正在用Javascript编写一个简单的程序。我无法弄清楚为什么程序无法正常工作。用户应该能够猜出一个数字，程序会告诉用户是否需要猜测更高或更低。现在，它甚至没有给我第一个提示。感谢您的帮助。

<html>
  <head>
  </head>
  <body>
    <script>
      //Guessing Game
      function guessingGame() {
        var userNumber = prompt("Pick a number 1 through 1000!", "Type your number here");
        var computerNumber = Math.floor(Math.random() * 1000 + 1);
        var tries = 0;
        var done = false;
        while (done === false) {
          if (userNumber < computerNumber) {
            document.write("Your number was too low.");
            tries = tries + 1;
            userNumber = prompt("Please guess again", "Type your number here");
          } else if (userNumber > computerNumber) {
            document.write("Your number was too high.");
            tries = tries + 1;
            userNumber = prompt("Please guess again", "Type your number here");
          } else {
            document.write("Great Job!!! You guessed the number in " + tries + " tries!" );
            done = true;
          }
        }
      }
      guessingGame();
    </script>
  </body>
</html>

Answer 1

document.write("Great Job!!! You guessed the number in " + tries " tries!" );

此行在+之后缺少tries。语法错误通常会导致整个JavaScript块被丢弃，因此无法运行。

if (userNumber < computerNumber) {

您还应该避免在JavaScript代码中使用未转义的<，因为它与HTML无法很好地混合。写下

if (userNumber &lt; computerNumber) {

或put the entire script into a CDATA section允许使用未转义的尖括号。

<script>
// <![CDATA[

    /* code here, can use '<' freely */

// ]]>
</script>

Answer 2

您忘记了行中的其他连接+：

document.write("Great Job!!! You guessed the number in " + tries " tries!" );

应该是

document.write("Great Job!!! You guessed the number in " + tries + " tries!" );

jsFiddle 上的固定示例。

Javascript程序无法正常工作

2 个答案: