Question

我在codepen上练习，出于某种原因，hte javascript代码中的AddtoInput函数似乎没有运行/编译。不确定它是否与html中的onclick有关，它很简单所以我不这么认为..

HTML代码

  <div id = "container">
    <div id="header">Calculator</div>
    <div id = "calculator">
      <div id="top">
        <div class="clear" onclick='Clear()'> C </div>
        <div class="screen">
          <input id="screen" type="text" placeholder="Let's do some math!"/></div>
      </div>
      <div class = "squares">
          <span onclick = "AddtoInput(1)">1</span>
          <span type="button" onclick="AddtoInput(2)">2</span>
          <span type="button" onclick='AddtoInput(3)'>3</span>
          <span class="operator add" onclick='oper(+)'>+</span>
          <span type="button" onclick="AddtoInput(4)">4</span>
          <span type="button" onclick="AddtoInput(5)">5</span>
          <span type="button" onclick="AddtoInput(6)">6</span>
          <span class="operator sub" onclick='oper(-)'>-</span>
          <span type="button" onclick="AddtoInput(7)">7</span>
          <span  onclick="AddtoInput(8)">8</span>
          <span type="button" onclick="AddtoInput(9)">9</span>
          <span class="operator" onclick='oper(/)'>÷</span>
          <span type="button" onclick="AddtoInput(0)">0</span>
          <span>.</span>
          <span class="equal" onclick='calc()'>=</span>
          <span class="operator" onclick='oper(*)'>x</span>
      <div>
     </div> 

   </div>

Javascript代码：

var operators = ['+', '-', '*', '/'];
var StringOper = '';
var InString = 0;
var InString2 = 0;
var elem = document.getElementById("screen");

function AddtoInput(num) {
  window.alert("I am In!!");
  InString = InString*10;
  InString = InString + num;
  elem.value = InString;
}

function Clear(){
  window.alert("I am In clear");
  InString = 0;
  elem.value = InString;
}

function oper(operator) {
  for (var i= 0,i<4;i++){
    if(operators[i] == operator)
      StringOper = operator;
  }
}

 function calc (){

 }

Answer 1

问题出在你的for循环中。

将其重写为：

function oper(operator) {
  for (var i = 0; i < 4; i++){
    if(operators[i] == operator)
      StringOper = operator;
  }
}

它应该有用。

问题是您在初始化和条件<之间的for语句中使用了逗号而不是分号 /强>

查看MDN document on for loops了解详情。

HTML onclick / JS功能不起作用

1 个答案: