File drag and drop is broken in MS Edge Creator's Edition. Reproducible in the following demo:

http://demos.telerik.com/aspnet-ajax/asyncupload/examples/draganddrop/defaultcs.aspx

RadAsyncUpload "Drop Files here" element remains visible when dragging a file quickly over and out of the DragZone

Replicable in File Upload with Drag and Drop live demo.

Drag a file quickly through the DragZone without dropping it. The "Drop Files Here" element is shown but doesn't get hidden when the mouse leaves the DragZone (ondragleave).

Upgrading to UI for ASP.NET AJAX Q2 2015 (2015.2.729.45) sets requestLimits maxAllowedContentLength in web.config to 

<requestLimits maxAllowedContentLength="0" /> <!--8MB Max upload-->

resulting in errors like "PRM_ServerError" on postbacks.

Hello,

I have a problem with postback on RadAsyncUpload in my project.

So, I created a simple project, with your example (https://docs.telerik.com/devtools/aspnet-ajax/controls/asyncupload/how-to/how-to-persist-uploaded-files) and the problem remains.

if I define PostbackTriggers on the aspx page, after the post back, I can see the files uploaded on the page, but the UploadedFiles.Count in code behind returns zero.

<telerik:RadAsyncUpload runat="server" ID="RadAsyncUpload1" PostbackTriggers="Button3,Button4"></telerik:RadAsyncUpload>

if I define PostbackTriggers on the aspx.vb page, after the post back I can't see the files uploaded on the page, but the UploadedFiles.Count in code behind returns 1.

RadAsyncUpload1.PostbackTriggers = New String() {Button1.ClientID, Button2.ClientID}

So, there is no way to, after the postback, present the uploaded files in page and values in  RadAsyncUpload.UploadedFiles.

Please, check the attach files.

Best Regards,

Mauro Santos

This issue is observed only in R1 2020. The solution is to not disable the FileAPI.

Reproduction steps:

<script>
    Telerik.Web.UI.RadAsyncUpload.Modules.FileApi.isAvailable = function () { return false; };
    Telerik.Web.UI.RadAsyncUpload.Modules.Flash.isAvailable = function () { return false; };
    Telerik.Web.UI.RadAsyncUpload.Modules.Silverlight.isAvailable = function () { return false; };
</script>
<telerik:RadAsyncUpload runat="server" ID="RadAsyncUpload1" ></telerik:RadAsyncUpload>

Documentation says Firefox should be ok with LastModifiedDate, but it's not.  It's consistently being set to 1/1/0001 12:00:00 AM, which is not useful.

Happens in any RadAsyncUpload example if you look at the value for LastModifiedDate in the AsyncUploadedFile objects.

Works fine in Chrome, Edge.  Fails in Firefox for Mac or Windows.

The drop zone and the custom drop zones are shifted below their expected positions in Edge 40.

Check the following video demonstration https://www.screencast.com/t/2m8SxR8jbwb.

The problem is reproducible in the http://demos.telerik.com/aspnet-ajax/asyncupload/examples/draganddrop/defaultcs.aspx demo.

Workaround: 

function encodeRowContent() {
    var asyncUpload = $find('<%= RadAsync_FileUpload.ClientID%>');
    var $ = $telerik.$;
    asyncUpload._updateRowContent = function (row, inputValue) {
        var $progress,
            $content = $("<span class='ruUploadProgress'>" + $telerik.htmlEncode(this._getFileName(inputValue)) + "</span>");

        $(row).removeClass("ruSelectWrap")
                .addClass("ruFileLI ruUploading")
                .prepend("<span class='radIcon'></span>");

        if (this._isManualUpload())
            $content.addClass("ruUploadOnHold");

        if (this._enableInlineProgress) {
            $progress = $('<span class="ruFileProgressWrap"><span class="ruFileProgress"></span></span>');
            $content.append($progress);
        }

        $('.ruFakeInput, .ruBrowse', row).remove();
        $(".ruFileWrap", row).append($content); // Replace fake input
    }
}

Sys.Application.add_load(encodeRowContent);

Workaround - Toggle drop zone visibility or enable/disable it, using AsyncUpload OnClientFileUploaded and OnClientFileUploadRemoved events:

<div class="dropfile" style="height: 20px; width: 120px; background-color: red; display: block">
</div>
<telerik:RadAsyncUpload ID="fimFileImport" runat="server" DropZones=".dropfile" MaxFileInputsCount="1"
	RenderMode="Lightweight" OnClientFileUploaded="OnClientFileUploaded" OnClientFileUploadRemoved="OnClientFileUploadRemoved" >
</telerik:RadAsyncUpload>

<script type="text/javascript">
	function OnClientFileUploaded(sender, args) {

		var maxFileCount = sender.get_maxFileCount();
		var uploadedFilesLength = sender.getUploadedFiles().length;
		
		if (maxFileCount === uploadedFilesLength) {
			$telerik.$('.dropfile').hide();
		}
	}

	function OnClientFileUploadRemoved(sender, args) {

		var maxFileCount = sender.get_maxFileCount();
		var uploadedFilesLength = sender.getUploadedFiles().length;

		if (maxFileCount > uploadedFilesLength) {
			$telerik.$('.dropfile').show();
		}
	}
</script>