如何使用JavaScript使上传图像功能而不复制图像

我尝试使用 javascript 制作上传图像文件功能，但我遇到了一些问题，当我删除(单击"X"(第一张图像并尝试重新上传另一张图像时，它将带有两个相同的图像，即它应该只出现一个，我需要只用 javascript 完成它，没有任何库，这是我下面的代码。

var container = document.querySelector('.image_container'); 
function upload(id,imageBox, deleteBtn){ 
 var inputTarget = document.getElementById(id); 
 var imageBox = document.getElementById(imageBox);
 var deleteBtn = document.getElementById(deleteBtn);
 var imagePrev = document.createElement('img');
  
  
inputTarget.addEventListener('change', function({target}){
    var file = target.files[0];
    var reader = new FileReader();
    reader.onload = function(e){ 
      deleteBtn.style.display = 'block';
      imageBox.style.display = 'none';
      imagePrev.src = e.target.result;
      imagePrev.className = id;
      container.appendChild(imagePrev);
    };
    reader.readAsDataURL(file);
  });
}
function deleteImg(id,imageBox,btnId){
  var targetInput = document.getElementById(id);
  var imageBox = document.getElementById(imageBox); 
  var imagePrev = document.querySelector('.'+id);
  var deleteBtn = document.querySelector('#'+btnId);
  imageBox.style.display = 'block';
  targetInput.value = "";
  deleteBtn.style.display = 'none';
  container.removeChild(imagePrev);
}

.image_container input[type="file"] {
    display: none;
}
.image_container #image_area1  {
    width: 100px;
    height: 100px;
    cursor: pointer;
    text-align: center;
    display: inline-block;
    line-height: 90px;
    background: rgb(211, 211, 211);
    border-radius: 3px;
    background-size: cover;           
    background-repeat: no-repeat;
    background-position: center center;
}
.image_container {
    display: inline-block;
}
button {
  display: block;
  margin: 20px 0;
}
#close_button {
  background: white;
    border-radius: 50px;
    width: 21px;
    height: 21px;
    text-align: center;
    position: absolute;
    top: 0;
    left: 0;
    cursor: pointer;
    display: none;
}

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width">
  <title></title>
</head>
<body>
<div class="image_container">
  <label>
    <input 
      type="file" 
      class="upload_button-first"
      id="target1"
      onclick="upload('target1','image_area1', 'close_button')">
    <span id="image_area1">upload image</span>   
  </label>
  <div id="close_button" onclick="deleteImg('target1','image_area1','close_button')">x</div>
</div>
</body>
</html>

您应该注册一次性事件，否则该事件将在您添加n图像时调用n次。

var handler = function(target) {
    var file = target.files[0];
    var reader = new FileReader();
    reader.onload = function(e) {
        deleteBtn.style.display = 'block';
        imageBox.style.display = 'none';
        imagePrev.src = e.target.result;
        imagePrev.className = id;
        container.appendChild(imagePrev);
    };
    reader.readAsDataURL(file);
    inputTarget.removeEventListener('change', handler);
};
inputTarget.addEventListener('change', handler);

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