Question

我想要做的是让用户键入一个数字，并根据他们键入的数字显示数组中的相应元素，但使用while循环并连接循环的结果。我尝试创建一个while循环，当变量大于或等于最小数组值时运行。但是我在尝试使所有这些事情发挥作用时遇到了很多问题。

  Name: <input type="text" id="myText" value="Mickey">
  <p id="demo"></p>
  <p>Click the button to change the value of the text field.</p>
     function myFunction() {
         var x = document.getElementById("myText");
         var currentVal = x.value;
         var jobs = ["Best Buy", "Staples", "Macys", "Dunkin Donuts", "Legal Aid"];
         var i = jobs.length - 1;
         while (jobs.length >= i) {
             document.getElementById("demo").innerHTML = jobs[i] + "&nbsp";
             break;
         }
     }

Answer 1

＆＃13;

public static double getBMIMetric()
{
    Scanner input = new Scanner(System.in);
    // Input Weight
    System.out.print("Enter your weight in kilograms: ");
    int weightKG = input.nextDouble();
    System.out.print("Enter your height in centimeters: ");
    int heightCM = input.nextInt();
    System.out.println();
    return weightKG/Math.pow(heightCM/100.0, 2);
}

public static void calculateMetricBMI()
{
    System.out.println("A body mass index of 20-25 is considered \"normal\"");
    double bmiMetric = getBMIMetric();
    System.out.print("Your BMI is " + bmiMetric);
}

＆＃13;

var input = document.getElementById("myText");
var demo  = document.getElementById("demo");
var jobs  = ["Best Buy","Staples","Macys","Dunkin Donuts","Legal Aid"];

function myFunction() {
  // Get val from array or fallback to empty String
  demo.innerHTML = jobs[this.value] || ""; 
}

input.addEventListener("input", myFunction);

＆＃13;

如果您希望用户输入要返回的项目数（从第一个数组键开始）：

＆＃13;

"What I want to do is have the user type a number
and based on the number they type it displays
the corresponding element"<br>


Type your Number: <input type="text" id="myText" value="">
<p id="demo"></p>

＆＃13;

var input = document.getElementById("myText");
var demo  = document.getElementById("demo");
var jobs  = ["Best Buy","Staples","Macys","Dunkin Donuts","Legal Aid"];

function myFunction() {
  // Get val from array or fallback to empty String
  demo.innerHTML = jobs.slice(0, this.value).join("<br>");
}

input.addEventListener("input", myFunction);

＆＃13;

Answer 2

我想要做的是让用户键入一个数字并基于它们键入的数字显示数组中的相应元素但是使用while循环并连接循环的结果。

尝试用input type="number"元素替换input type="text"元素; onchange事件;用+=运算符替换while循环以将.innerHTML元素与id demo连接起来，Array.prototype.splice()

＆＃13;

Name:
<input type="number" min="0" max="4" id="myText" value="Mickey">
<p id="demo"></p>
<p>Click the button to change the value of the text field.</p>
<script>
  var x = document.getElementById("myText"),
    demo = document.getElementById("demo"),
    jobs = ["Best Buy", "Staples", "Macys", "Dunkin Donuts", "Legal Aid"];

  function myFunction() {
    var val = jobs.splice(this.value, 1);
    demo.innerHTML += val + "&nbsp";
  }

  x.onchange = myFunction; x.focus();
  
</script>

＆＃13;

当用户选择哪个元素来查看Javascript时，如何遍历数组

2 个答案: