asp.net core分块上传文件示例

2019-05-25 23:11:51于海丽

写完asp.net多文件上传后,感觉这种上传还是有很多缺陷,于是。。。(省略一万字,不废话)。这里我没用传统的asp.net,而选择了开源的asp.net core,原因很简单,.net core是.net新的开始,更是.net和.net开发者的未来,希望.net发展越来越好(大家的工资越来越高(●ˇ∀ˇ●))。

1.前端的实现:

1).html: 

<html>
<head>
  <meta name="viewport" content="width=device-width" />
  <title>Index</title>
  <link href="/lib/bootstrap/dist/css/bootstrap.css" rel="external nofollow" rel="stylesheet" />
  <script src="/lib/jquery/dist/jquery.js"></script>
  <script src="/lib/bootstrap/dist/js/bootstrap.js"></script>
  <script src="/js/UploadJs.js"></script>
</head>
<body>
  <div class="row" style="margin-top:20%">
    <div class="col-lg-4"></div>
    <div class="col-lg-4">
      <input type="text" value="请选择文件" size="20" name="upfile" id="upfile" style="border:1px dotted #ccc">
      <input type="button" value="浏览" onclick="path.click()" style="border:1px solid #ccc;background:#fff">
      <input type="file" id="path" style="display:none" multiple="multiple" onchange="upfile.value=this.value">
      <br />
      <span id="output">0%</span>
      <button type="button" id="file" onclick="UploadStart()" style="border:1px solid #ccc;background:#fff">开始上传</button>
    </div>
    <div class="col-lg-4"></div>
  </div>
</body>
</html>

2).javascript:

var UploadPath = "";
//开始上传
function UploadStart() {
  var file = $("#path")[0].files[0];
  AjaxFile(file, 0);
}
function AjaxFile(file, i) {
  var name = file.name, //文件名
  size = file.size, //总大小shardSize = 2 * 1024 * 1024, 
  shardSize = 2 * 1024 * 1024,//以2MB为一个分片
  shardCount = Math.ceil(size / shardSize); //总片数
  if (i >= shardCount) {
    return;
  }
  //计算每一片的起始与结束位置
  var start = i * shardSize,
  end = Math.min(size, start + shardSize);
  //构造一个表单,FormData是HTML5新增的
  var form = new FormData();
  form.append("data", file.slice(start, end)); //slice方法用于切出文件的一部分
  form.append("lastModified", file.lastModified);
  form.append("fileName", name);
  form.append("total", shardCount); //总片数
  form.append("index", i + 1); //当前是第几片
  UploadPath = file.lastModified
  //Ajax提交文件
  $.ajax({
    url: "/Upload/UploadFile",
    type: "POST",
    data: form,
    async: true, //异步
    processData: false, //很重要,告诉jquery不要对form进行处理
    contentType: false, //很重要,指定为false才能形成正确的Content-Type
    success: function (result) {
      if (result != null) {
        i = result.number++;
        var num = Math.ceil(i * 100 / shardCount);
        $("#output").text(num + '%');
        AjaxFile(file, i);
        if (result.mergeOk) {
          var filepath = $("#path");
          filepath.after(filepath.clone().val(""));
          filepath.remove();//清空input file
          $('#upfile').val('请选择文件');
          alert("success!!!");
        }
      }
    }
  });
}