js를 사용하여 양식에 여러 파일 업로드를 구현하는 예제 코드

<!--文件上传-->
 <form id="uploadForm" enctype="multipart/form-data">
 <p class="row" style="margin-top: 20px;">
  <p class="form-group col-md-12" id="file">   
   <input type="hidden" name="_csrf-application"
     value="<?= $csrf ?>">
   <p class="form-group field-uploadform-excelfiles" style="margin-left: 30px;">
    <label class="control-label btn btn-primary"
      for="uploadform-excelfiles">选择文件</label>
    <input type="file" id="uploadform-excelfiles" name="UploadForm[excelFiles][]"
      multiple class="attachment-upload" accept=".xlsx">
    <input type="button" id="fileUpload" value="上传文件" class="btn btn-success" style="margin-left: 15px;">
    <p class="help-block"></p>
    <p id="fileName"></p>
   </p>

  </p>
 </p>
 <table role="presentation" class="table"><tbody id="files"></tbody></table> 
</form>

 var fileList;
 var allFile = [];
 //FormData对象初始化
 var form = document.getElementById("upload-form");
 var formData = new FormData(form);
 $("#uploadform-excelfiles").on('change', function (e) {
  //获取表单数据并传入formData中
  var norm = $("#norm").val();
  var major = $("#major").val();
  var type = $("#type").val();
  formData.set("norm",norm);
  formData.set("major",major);
  formData.set("type",type);

  var fileError = 0;
  fileList = e.currentTarget.files;
  $.each(fileList, function (index, item) {
   var fileName = item.name;
   var fileEnd = fileName.substring(fileName.indexOf("."));
   //上传文件格式判断
   if (fileEnd == ".xlsx") {
    allFile.push(item);
    $(&#39;#files&#39;).append( &#39;<tr style="padding-top: 7px;">&#39; +
         &#39;<td>&#39;+fileName+&#39;</td>&#39; +
         &#39;<td>&#39;+(item.size / 1024).toFixed(2)+&#39;K</td>&#39; +
         &#39;<td><input type="button" class="btn btn-danger delete" value="删除"></td>&#39; +
         &#39;</tr>&#39;);
    //追加文件
    formData.append(&#39;UploadForm[excelFiles][]&#39;,item);
   } else {
    fileError++;
   }
  });
  if (fileError > 0) {
   alert("只能上传 “.xlsx” 格式的文件!");
   document.getElementById("upload-form").reset();
   return;
  }

  var fileCount = $(&#39;#files&#39;).find(&#39;tr&#39;).length;
  $(&#39;#fileName&#39;).html(&#39;共上传 &#39; + fileCount + &#39; 个文件&#39;);

 });

$('#files').on('click','.delete',function (e) {
  var saveFile = [];
  var norm = $("#norm").val();
  var major = $("#major").val();
  var type = $("#type").val();
  var deleteName = e.target.parentNode.previousElementSibling.previousElementSibling.textContent;
  var deleteIndex;
  //将不删除的放入数组中
  $.each(allFile,function (index, item) {
   if(item.name == deleteName){
     deleteIndex = index;
   }else {
    saveFile.push(item);
   }
  });
  allFile.splice(deleteIndex,1);
  //表单数据重置
  formData.set("norm",norm);
  formData.set("major",major);
  formData.set("type",type);
  formData.delete('UploadForm[excelFiles][]');
  //将不删除的数组追加的formData中
  $.each(saveFile,function (index, item) {
   formData.append('UploadForm[excelFiles][]',item);
  });

  e.target.parentNode.parentNode.remove();
  var fileCount = $('#files').find('tr').length;
  $('#fileName').html('共上传 ' + fileCount + ' 个文件');

 });