What is the best way to upload files with ASP.NET MVC 2?
What is the best method for uploading files of variable size (either very large or very small to an ASP.NET MVC 2 application file system)?
This is what I understand so far:
It seems like there are two ways that people handle this. (Let's assume the files may be very large or very small)
(1) Handle the upload in a controller action via Request.Files
or HttpPostedFileBase
, which seems to have a drawback of taking a long time because ASP.NET loads the files into active memory.
or
(2) intercept the file upload early on with an HttpModule which somehow circumvents the performance issue. (I'm a little cloudy on how this works, but I've been using this post http://darrenjohnstone.net/2008/07/15/aspnet-file-upload-module-version-2-beta-1/ as a reference). The part I'm fuzzy about is at what point ASP.NET loads the submitted files to active memory, and how intercepting this in a module actually changes this behavior.
Since the second option is faster, it seems like the better option. But it seems like an application submitting an upload form will probably have some data associated with the file that needs to be persisted in a database. I don't want to make persistence calls in my HttpHandler or HttpModule, (because then I will have two very similar functionalities occurring in different places : the controller and the http handler).
I guess one work around would be to store the target file location in HttpContext.Items, but is this the best way?
One last concern about this is that I want to render an HttpResponse before the file is finished uploading. So, if 开发者_运维问答there is a big file, I will send the user a view with the value of the upload status, and make AJAX calls to keep the status updated. How do I render a result, while keeping the upload process going? Do I need to make an AsyncHandler or AsyncController? Do I need to manually grab another thread?
Thanks a lot guys. I know this is a lot of questions, and probably reflects a general lack of understanding about something. The funny thing about general lacks of understanding is that people who have them also tend to lack the understanding of what understanding they are lacking...so, if anyone can point me in the right direction on that note as well, I would appreciate it.
If I remember correctly from ASP.NET 2.0 large files are being flushed to disk, so even using HttpPostedFileBase there should not be any memory/performance problems. I am not sure asynccontrollers is an solutions here, asynccontrollers is for long running server processes. For an example off AsyncControllers see http://www.aaronstannard.com/post/2011/01/06/asynchonrous-controllers-ASPNET-mvc.aspx
I use this javascript tool
This is the controller (I double check cause IE has a strange behavior) :
<HttpPost()> _
Function UploadExcelPriceList(ByVal id As String) As System.String
Dim bResult As Boolean = False
Dim IsIE As Boolean = False
Dim sFileName As String = ""
If (Request.Files Is Nothing) OrElse (Request.Files.Count = 0) Then
If String.IsNullOrEmpty(Request.Params("qqfile")) Then
Return ("{success:false, error:'request file is empty'}")
Else
sFileName = Request.Params("qqfile").ToString
End If
Else
sFileName = Request.Files(0).FileName
IsIE = True
End If
If String.IsNullOrEmpty(sFileName) Then
Return ("{success:false, error:'request file is empty'}")
End If
Dim DocumentName As String = Id & Path.GetExtension(sFileName)
If IsIE Then
Try
Request.Files(0).SaveAs(Path.Combine(My.Settings.TempFolder, DocumentName))
Catch ex As Exception
Return ("{success:false, error:'" & ex.Message & "'}")
End Try
Else
Try
If (Request.InputStream IsNot Nothing) AndAlso (Request.InputStream.CanRead) AndAlso (Request.InputStream.Length > 0) Then
Using fileStream As FileStream = New FileStream(Path.Combine(My.Settings.TempFolder, DocumentName), FileMode.Create)
Dim FileBytes(Core.Convert.ToInt32(Request.InputStream.Length)) As Byte
Dim bytesRead As Int32 = 0
bytesRead = Request.InputStream.Read(FileBytes, 0, FileBytes.Length)
fileStream.Write(FileBytes, 0, bytesRead)
fileStream.Flush()
fileStream.Close()
bytesRead = Nothing
End Using
End If
Catch ex As Exception
Return ("{success:false, error:'" & ex.Message & "'}")
End Try
End If
Return ("{success:true, id: '" & Id & "'}")
End Function
I put this HTML in my View:
<div id="PopupExcelUploader" title="Carica Listino Excel">
<div id="uploaderFile"></div>
</div>
and this is the javascript:
function CreateFileUploader() {
var uploader = new qq.FileUploader({
element: $('#uploaderFile')[0],
template: '<div class="qq-uploader">' +
'<div class="qq-upload-drop-area"><span>Drop files here to upload</span></div>' +
'<div class="qq-upload-button ui-button ui-widget ui-corner-all ui-button-text-only ui-state-default">Seleziona il Listino Excel</div>' +
'<ul class="qq-upload-list"></ul>' +
'</div>',
hoverClass: 'ui-state-hover',
focusClass: 'ui-state-focus',
action: UploaderAction,
allowedExtensions: ['xls', 'xlsx'],
params: { id: ModelId },
onSubmit: function(file, ext) {
},
onComplete: function(id, fileName, responseJSON) {
if ((responseJSON.success == null) || (responseJSON.success == 'false')) {
$.jGrowl("Error!", { theme: 'MessageError', life: 3000 });
}
else {
documentUploaded = true;
$.jGrowl("Document uploaded successfully!", { theme: 'MessageOk', life: 1800 });
window.setTimeout(function() {
$("#PopupExcelUploader").dialog('close');
$("#PriceListDynamicGrid").trigger("reloadGrid");
}, 3000);
}
}
});
}
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