如何在更新/编辑表单期间显示所选的上载文件？

Question

我有一个包含多个文件上传字段的表单，我已经成功在/ upload文件夹中上传了多个文件。 但是现在当我编辑表单时，我想将以前上传的文件显示为选定的文件，在这里我可以更改文件，添加新文件或删除文件。

   echo form_open_multipart(site_url()."lead/update/$lead->id"); 
        ?>
          <div class="box-body">
             <div class="form-group">
              <label for="InputFirstName">First name</label>

              <input type="text" class="form-control" id="InputFirstName" name="InputFirstName" placeholder="Enter first name" value="<?php echo $lead->fname; ?>">

            </div>
             <div class="form-group">
              <label for="InputLastName">Last name</label>
              <input type="text" class="form-control" id="InputLastName" name="InputLastName" placeholder="Enter last name" value="<?php echo $lead->lname; ?>">
            </div>
            <div class="form-group">
              <label for="InputEmail1">Email address</label>
              <input type="email" class="form-control" id="InputEmail1" name="InputEmail1" placeholder="Enter email" value="<?php echo $lead->email; ?>">
              <?php echo form_error('InputEmail1', '<span class="help-block">', '</span>'); ?>

            </div>

             <div class="form-group">
              <label for="InputContact">Contact number</label>
              <input type="text" class="form-control" id="InputContact" name="InputContact" placeholder="Enter contact number" value="<?php echo $lead->phone; ?>">

            </div>

            <div class="form-group">

                <label for="InputSource">Source</lable>
                <select name="source" id="InputSource" class="form-control">
                  <option value="Email"<?php if($lead->source=='Email') echo 'selected="selected"';?>>Email</option>
                  <option value="Phone"<?php if($lead->source=='Phone') echo 'selected="selected"';?>>Phone</option>
                  <option value="Website"<?php if($lead->source=='Website') echo 'selected="selected"';?>>Website</option>
                </select>

            </div>

            <div class="form-group">
              <label for="InputStatus">Status</label>
              <select name="status" id="InputStatus" class="form-control">
                <option value="Draft"<?php if($lead->status=='Draft') echo 'selected="selected"';?>>Draft</option>
                <option value="In Progress" <?php if($lead->status=='In Progress') echo 'selected="selected"';?>>In Progress</option>
                <option value="Responsible Assigned" <?php if($lead->status=='Responsible Assigned') echo 'selected="selected"';?>>Responsible Assigned</option>
              </select>


            </div>

            <div class="form-group">
              <label for="exampleInputFile">Add Attachments</label>
              <input type="file" id="files" name="files[]">
              <div class="contents"></div>
              <div>
                <a href="javascript:void(0);" class="add">Add more</a>
              </div>
            </div>
          </div>
           <!-- /.box-body -->

          <div class="box-footer">
            <?php echo form_submit(array('value'=>'Submit', 'class'=>'btn btn-primary btn_add', 'name'=>'SAVE')); ?>
          </div>
          <?php echo form_close(); ?>

这是我的代码