如果第一个提示不是 TRUE，则显示第二个提示答案

【问题标题】：Display second prompt if the first prompt is not TRUE如果第一个提示不是 TRUE，则显示第二个提示
【发布时间】：2022-02-12 16:22:08
【问题描述】：

当我尝试显示新提示时遇到问题，我使用循环，但它会同时显示我的提示。这是我的代码，我真的需要帮助

<body>
<p id="age" style="font-weight: bold"></p>
<button onclick=" notify()">Try it</button>
<script>
function notify(){
var age = document.getElementById("age").value;
var age = prompt("Enter Your birth year:");// This is the first prompt 
const year = new Date().getFullYear();
if (age != null) { 
          document.getElementById("age").innerHTML =
            "Your " + age + " is so beautiful"; // If user enter birth year < current year will display this
        }
  do {
     age = prompt("Re-enter your birth year:"); // Ortherwise, this will display and they need to enter until birth year < current year
    } while (age > year && age != null);
        var tuoi = year - age;// This is just calculate user'age, for example if the user enter 2000 will display user'age is 22
        document.getElementById("age").innerHTML =
          "Tuổi " + tuoi + " này đẹp đó";
}
</script>
</body>

【问题讨论】：

标签： javascript html css

【解决方案1】：

您的代码有几个问题，并且做了一些对我来说完全没有意义的事情，但我认为您想要这样的事情：

<body>
  <p id="age" style="font-weight: bold"></p>
  <button onclick=" notify()">Try it</button>
  <script>
    function notify() {
      const year = new Date().getFullYear();
      var birth_year = parseInt(prompt("Enter Your birth year:")); // This is the first prompt
      
      if (!isNaN(birth_year) && birth_year < year) {
        document.getElementById("age").innerHTML =
          "Your " + birth_year + " is so beautiful"; // If user enter birth year < current year will display this
      } else {
        do {
          birth_year = parseInt(prompt("Enter Your birth year:")); // Ortherwise, this will display and they need to enter until birth year < current year
        } while (isNaN(parseInt(birth_year)) || birth_year >= year);
        var tuoi = year - age; // This is just calculate user'age, for example if the user enter 2000 will display user'age is 22
        document.getElementById("age").innerHTML =
          "Tuổi " + birth_year + " này đẹp đó";
      }
    }

  </script>
</body>

【讨论】：

【解决方案2】：

你只是忘记了你的 if 条件的一部分。

将if (age != null) 更改为if (age != null && age < year)，它将按您的预期工作。如果年龄 == 年，请不要忘记大小写。

【讨论】：