Javascript 提示框循环答案

【问题标题】：Javascript Prompt Box LoopsJavascript 提示框循环
【发布时间】：2017-07-30 23:32:16
【问题描述】：

这段代码有问题，但我不知道它是什么。该页面无法正常工作或无法正常工作。我需要一个提示输入密码并将尝试次数限制为 3 次的代码。第三次尝试后，它需要有一个警告框。我还没有添加警报框之后的内容。

<script>
var attempts = 3;
var answer = prompt("Password: ");
while (attempts != 0) 
{
    if (answer == "Psycho")
    {
        document.write("These are pictures of my kitten and     her things.");
    }
    else
    {
        answer = prompt("Password: ");
        attempts--;
    }
}
if (attempts = 0) 
{
    alert("Incorrect Password");
}
</script>

【问题讨论】：

= 是分配

标签： javascript loops if-statement while-loop prompt

【解决方案1】：

有几个选项可以修复您的代码。完成工作后您可以返回。

<script>
var attempts = 3;
var answer = prompt("Password: ");
while (attempts != 0) 
{
    if (answer == "Psycho")
    {
        document.write("These are pictures of my kitten and     her things.");
        return;
    }
    else
    {
        answer = prompt("Password: ");
        attempts--;
    }
}
if (attempts == 0) 
{
    alert("Incorrect Password");
}
</script>

或者，如果你失败了，我会早点回来

<script>
var attempts = 4;
var answer = prompt("Password: ");
while (attempts > 0 && answer != "Psycho") 
{
    answer = prompt("Password: ");
    attempts--;
}

if (attempts == 0) 
{
    alert("Incorrect Password");
}
else
{
    document.write("These are pictures of my kitten and     her things.");
}
</script>

【讨论】：

@epascarello doh！固定

【解决方案2】：

您有几个问题。您应该在用户输入提示后检查条目。否则不会检查最后一个条目。下一个问题是您没有退出循环。另一个问题是 = 是赋值，所以如果你赋值为零，而不是检查它是否为零。

var attempts = 3;
while (attempts > 0) {
  var answer = prompt("Password: ");
  if (answer == "Psycho") {
    document.write("These are pictures of my kitten and her things.");
    break;
  }
  attempts--;
}
if (attempts == 0) {
  alert("Incorrect Password");
}

【讨论】：