Valums Uploader额外请求有效负载已添加到文件

Question

I'm trying to set up the Valums File Uploader ( https://github.com/valums/file-uploader ), using ASP.NET in VB. The file is currently uploading and storing where I want it to and appears to be working, however it appears that both Firefox and Chrome (I assume Safari as well) append some additional text to the actual CSV file that is being uploaded.

For example, this is what I see in a file uploaded through Firefox:

-----------------------------31203180683076
Content-Disposition: form-data; name="qqfile"; filename="test.csv"
Content-Type: application/vnd.ms-excel

/* ACTUAL CONTENTS OF FILE HERE */

-----------------------------31203180683076--

And similarly, Chrome:

------WebKitFormBoundarytB00bSQcafSOAnmq
Content-Disposition: form-data; name="qqfile"; filename="test.csv"
Content-Type: application/vnd.ms-excel

/* ACTUAL CONTENTS OF FILE HERE */

------WebKitFormBoundarytB00bSQcafSOAnmq--

If I view the network panel in Chrome I do see exactly what is posted above being sent in the Request Payload, however I would like to either remove that, or completely ignore it on the server when it goes to write the file. I thought I had found the solution when I added paramsInBody: false to the uploader, and it did remove some of the mess, but not all of it.

Below is the relevant code on the client-side:

function createUploader() {
    var uploader = new qq.FineUploader({
        element: document.getElementById('bootstrapped-fine-uploader'),
        request: {
            paramsInBody: false,
            endpoint: 'Uploader.ashx'
        },
        validation: {
            allowedExtensions: ['csv', 'txt']
        },
        text: {
            uploadButton: '<div><i class="icon-upload-alt icon-white"></i> Browse for files...</div>'
        },
        template: '<div class="span12"><div class="qq-uploader">' +
                  '<pre class="qq-upload-drop-area span12"><span>{dragZoneText}</span></pre>' +
                  '<div class="qq-upload-button btn btn-success" style="width: auto;">{uploadButtonText}</div>' +
                  '<span class="qq-drop-processing"><span class="qq-drop-processing-spinner"></span></span>' +
                  '<ul class="qq-upload-list" style="margin: 0; list-style-type: none; margin-top: 20px;"></ul>' +
                '</div></div>',
        classes: {
            success: 'alert alert-success',
            fail: 'alert alert-error'
        }
    });
}

And here is the relevant server-side handler:

Public Sub ProcessRequest(ByVal context As HttpContext) Implements IHttpHandler.ProcessRequest
    On Error GoTo upload_error

    Dim Request = context.Request
    Dim strm As Stream = Request.InputStream
    Dim br As BinaryReader = New BinaryReader(strm)
    Dim fileContents() As Byte = {}
    Const ChunkSize As Integer = 1024 * 1024

    ' We need to hand IE a little bit differently...
    If Request.Browser.Browser = "IE" Then
        Dim myfiles As System.Web.HttpFileCollection = System.Web.HttpContext.Current.Request.Files
        Dim postedFile As System.Web.HttpPostedFile = myfiles(0)
        If Not postedFile.FileName.Equals("") Then
            Dim fn As String = System.IO.Path.GetFileName(postedFile.FileName)
            br = New BinaryReader(postedFile.InputStream)
        End If
    End If

    ' Now have the binary reader on the IE file input Stream. Back to normal...
    Do While br.BaseStream.Position < br.BaseStream.Length - 1
        Dim b(ChunkSize - 1) As Byte
        Dim ReadLen As Integer = br.Read(b, 0, ChunkSize)
        Dim dummy() As Byte = fileContents.Concat(b).ToArray()
        fileContents = dummy
        dummy = Nothing
    Loop

    ' Or write it to the filesystem:
    Dim writeStream As FileStream = New FileStream("C:\TEMP\" & System.Guid.NewGuid.ToString() & ".csv", FileMode.Create)
    Dim bw As New BinaryWriter(writeStream)
    bw.Write(fileContents)
    bw.Close()

    ' it all worked ok so send back SUCCESS is true!
    context.Response.Write("{""success"":true}")
    Exit Sub

upload_error:
    context.Response.Write("{""error"":""An Error Occured""}")
End Sub

Any ideas on why it would be working this way? Thanks a lot.

Answer 1

I was able to fix the issue by removing the browser check in the VB code. Instead of checking for IE, I just let it run for all browsers.

While running a Debug I noticed that some of the stuff was pulled out that I wanted to be pulled out using the code inside that conditional, so I tried running it using Chrome and it ran through fine.

The code now looks like this for VB. All I had to do was comment out the conditional and leave the insides intact:

'Removed the If conditional and it worked.
'If Request.Browser.Browser = "IE" Then
    Dim myfiles As System.Web.HttpFileCollection = System.Web.HttpContext.Current.Request.Files
    Dim postedFile As System.Web.HttpPostedFile = myfiles(0)
    If Not postedFile.FileName.Equals("") Then
        Dim fn As String = System.IO.Path.GetFileName(postedFile.FileName)
        br = New BinaryReader(postedFile.InputStream)
    End If
'End If