Question

初学者使用javascript，遇到表单问题，用户输入5个整数然后进入数组然后计算总和使用google web dev工具获取事件监听器的错误。我离开了吗？

HTML

<article>
<h2> Enter five intergers then click add to calculate the sum </h2>
<h5>please do not include any letters</h5><br>
<br>Enter the 1st number: <input type="text" id="txt1" /><br>
<br>Enter the 2nd number: <input type="text" id="txt2" /><br>
<br>Enter the 3rd number: <input type="text" id="txt3" /><br>
<br>Enter the 4th number: <input type="text" id="txt4" /><br>
<br>Enter the 5th number: <input type="text" id="txt5" /><br>

<br><input type="button" onclick="call()" value="Add" id="sum" />
<br>
</article>

JAVASCRIPT

function add () {
var txt1  = document.getElementById("txt1");
var txt2  = document.getElementById("txt2");
var txt3  = document.getElementById("txt3");
var txt4  = document.getElementById("txt4");
var txt5  = document.getElementById("txt5");


var arr = [txt1,txt2,txt3,txt4,txt5];
var total=0;
for(var i in arr) { total += arr[i]; }
   if(isNaN(txt1)||isNaN(txt2)||isNaN(txt3)||isNaN(txt4)||isNaN(txt5)){
          alert("please enter a number");
     }
     else

        {

         var result=txt1+txt2+txt3+txt4+txt5;
         alert("The sum is " +result);
       }
       }
      // listener
      function createEventListener() {
         var submitButton = document.getElementById("sum");
         if (submitButton.addEventListener) {
           submitButton.addEventListener("click", add, false); 
         } else if (submitButton.attachEvent)  {
           submitButton.attachEvent("onclick", add);
         }
         document.getElementById('result').result = ""; 
         document.getElementById('sum').innerHTML = ""; 
      }

      if (window.addEventListener) {
         window.addEventListener("load", createEventListener, false);
      } else if (window.attachEvent) {
         window.attachEvent("onload", createEventListener);
      }

Answer 1

您的onclick正在调用您尚未定义的call（）。我认为你的意思是add（）

Answer 2

首先，它应该是add，而不是call：

<input type="button" onclick="add()" value="Add" id="sum" />

然后必须改变这些：

var txt1 = Number(document.getElementById("txt1").value);

计算用户输入整数的数组之和时遇到问题

2 个答案: