Javascript 上传图片可以'；检测不到按钮的变化

下面是我上传图片的代码。我有个问题

情景

当我上传一张图片，然后它完成按钮改变它没有点击

第二种方法与上传图片时按钮按下但不改变图片时的

#1

完全相反

我的目标是上传图片后，我想要上传图片的大小

（例如40kb）

正如您在代码中看到的，我有按钮更改代码和onComplete函数代码。但是在onComplete函数中，

文件的值为空

JS

jQuery(document).ready(function () {
var btnUploadDrvr = $("#btnUpload201Doc");
var hidFilenameDrvr = $("#EmpDocimg");
var extension;
$("#btnUpload201Doc").change(function (e) {
    alert(e.target.files[0].size);
    //e.target.files[0];
});
InitAjaxUpload(btnUploadDrvr, hidFilenameDrvr);

function InitAjaxUpload(btnUpload, imgHolder) {
    new AjaxUpload(btnUpload, {
        action: '../UploadDownload/UploadLocalPic',
        data: '',
        name: 'uploadfile',
        onSubmit: function (file, ext) {
            debugger;
            extension = ext[0];
            if (!(ext && /^(jpg|png|jpeg|gif|pdf|PDF)$/.test(ext))) {
                // extension is not allowed 
                //status.text('Only JPG, PNG, GIF, PDF files are allowed');
                alert("Only JPG, PNG, GIF, PDF files are allowed.");
                return false;
            }
        },
        onComplete: function (file, response) {
            debugger;
            $("#btnSave201Doc")[0].files[0].size;
    });
}
});

控制器

   public void UploadLocalPic()
    {

        HttpPostedFileBase file = Request.Files[0];// as HttpPostedFileBase;


        string nm = file.FileName;
        string contentType = "";
        MemoryStream ws = new MemoryStream();
        var imageBytes = ws.ToArray();


        if (file != null && file.ContentLength > 0)
        {
            // extract only the fielname
            var fileName = Path.GetFileName(file.FileName);
            string filename = Convert.ToString((DateTime.Now.Month) + Convert.ToString(DateTime.Now.Day) + Convert.ToString(DateTime.Now.Year) + Convert.ToString(DateTime.Now.Hour) + Convert.ToString(DateTime.Now.Minute) + Convert.ToString(DateTime.Now.Second) + Convert.ToString(DateTime.Now.Millisecond)) + fileName;
            var len = file.ContentLength;
            var type = file.ContentType;
            Stream strm = file.InputStream;

            MemoryStream writeStream = new MemoryStream();
            Int32 chunksize = 2048;
            //variable declaration of byte array with the size of chunksize
            Byte[] buffer = new Byte[chunksize];

            //Write to a memorystream from stream
            do
            {
                Int32 bytesRead = strm.Read(buffer, 0, chunksize);
                if (bytesRead == 0)
                {
                    break;
                }
                writeStream.Write(buffer, 0, bytesRead);
            } while (true);
            imageBytes = writeStream.ToArray();
            string ext1 = Getextension(nm);
            string ext = ext1.ToLower();
            contentType = "image/png";

            //content type is based on the file extension
            if ((ext == "jpeg") || (ext == "png"))
            {
                contentType = "image/png";
            }
            else if (ext == "txt")
            {
                contentType = "text/html";
            }
            else if (ext == "pdf")
            {
                contentType = "application/pdf";
            }
            var by = imageBytes;
        }
        var data = Convert.ToBase64String(imageBytes);
        HttpContext.Response.Write(data);
    }

HTML

< input id="btnUpload201Doc" type="file" value="Browse..." class="button" disabled="disabled" style="width: 72px" />