Question

我是一个新手自学如何通过udemy.com使用课程编写代码。我正在学习Javascript，作为一个项目，我们被指示创建一个简单的Javascript游戏。基本上你输入一个你认为计算机正在思考的数字。到目前为止，当您输入正确的数字并单击提交时，将出现一个框，表明＆＃34;耶！这就是我举起的手指的数量！＆＃34;或者如果它不正确，它将说明＆＃34;抱歉这不正确，我的号码是......＆＃34;

问题是我无法弄清楚如何添加额外的if语句。例如，我试图提醒一条消息，说明你需要输入一个数字＆＃34; o;当用户单击提交按钮而不在框中输入数字或字母时。当他们猜到0的正确数字时，警告信息将显示＆＃34;那是对的，我没有手指！＆＃34;

以下是允许我正确执行上面列出的两条指令的代码：

<p>How many fingers am I holding up?</p>
<input id="answer"/>
<button id="myButton"><strong>Submit</strong></button> 
<script type="text/javascript">
document.getElementById("myButton").onclick=function() {
    var x=Math.random();
    x=6*x;
    x=Math.floor(x); //use floor to get whole number

    if (x==document.getElementById("answer").value) {
        alert("Yay! That's exactly how many fingers I'm holding up!"); 
    } else {
        alert("Sorry that's not correct! My number was" + x );
    }
}
</script>

我在这里做错了什么？

提前致谢！

Answer 1

var x = Math.random();
x = 6*x;
x = Math.floor(x); //use floor to get whole number
var y = document.getElementById("answer").value;

if(y == null){
    alert("Please enter a number");
}else{
    if (x == y) {
        if(x == 0){
            alert("Yay! I'm not holding any fingers up!"); 

        }else{
            alert("Yay! That's exactly how many fingers I'm holding up!"); 
        }
    } else {    
        alert("Sorry that's not correct! My number was" + x );
    }
}

Answer 2

这是一个修改过的脚本，问题在于.value属性。请修改你的缩进。

请点击此链接查看完整代码JS fiddle

document.getElementById("myButton").onclick = function() {
  var x = Math.random();
  var y = document.getElementById("answer");
  x = 6 * x;
  x = Math.floor(x); //use floor to get whole number

  if (y.value === "") {
    alert("Oops, you need to enter a number!");
  } else if (x == y.value) {
    if (x == 0) {
      alert("That's right, I have no fingers up!");
    } else {
      alert("Yay! That's exactly how many fingers I'm holding up!");
    }
  } else {
    alert("Sorry that's not correct! My number was " + x);
  }
}

为简单的javascript游戏添加更多If语句

2 个答案: