FileUploadCompleteEventArgs.CallbackData Property

Gets or sets a string that contains specific information (if any) to be passed from the server side to the client.

Namespace: DevExpress.Web

Assembly: DevExpress.Web.v23.2.dll

NuGet Package: DevExpress.Web

Declaration

C#

public string CallbackData { get; set; }

VB.NET

Public Property CallbackData As String

Property Value

Type	Description
String	A String value representing callback data.

Remarks

Use the CallbackData property to define specific information which has been collected on the server side, and should be passed to the client for further processing within the ASPxClientUploadControl.FileUploadComplete client event.

The example below demonstrates how to upload an image to the server and display the uploaded image on a web page:

<script type="text/javascript">
    function OnFileUploadComplete(s, e) {
        document.getElementById('image').src = e.callbackData;
    }
</script>
<form id="form1" runat="server">
    <div>
        <dx:ASPxUploadControl ID="Upload" runat="server" ShowUploadButton="True" OnFileUploadComplete="Upload_FileUploadComplete">
            <ValidationSettings AllowedFileExtensions=".jpg,.jpeg,.jpe,.gif">
            </ValidationSettings>
            <ClientSideEvents FileUploadComplete="OnFileUploadComplete" />
        </dx:ASPxUploadControl>
        <br />
        <img src="Images/DefaultImage.jpg" id="image" alt="Please load image" />
    </div>
</form>

protected void Upload_FileUploadComplete(object sender, FileUploadCompleteEventArgs e)
{
    e.CallbackData = String.Format("Images\\Picture{0}.jpg", DateTime.Now.ToString("yyyy-MM-dd hh-mm-ss"));
    string path = Page.MapPath("~/") + e.CallbackData;
    e.UploadedFile.SaveAs(path);
}

View Example: Upload Control for ASP.NET Web Forms - How to upload an image and display it on a web page

Related GitHub Examples

The following code snippets (auto-collected from DevExpress Examples) contain references to the CallbackData property.

Note

The algorithm used to collect these code examples remains a work in progress. Accordingly, the links and snippets below may produce inaccurate results. If you encounter an issue with code examples below, please use the feedback form on this page to report the issue.

C#

asp-net-mvc-grid-upload-excel-file-using-upload-control-and-display-data-in-grid/CS/T449148/Controllers/HomeController.cs#L58

e.UploadedFile.SaveAs(resultFilePath);
e.CallbackData = resultFilePath;

asp-net-mvc-grid-upload-and-display-excel-file/CS/UploadControlApplication/Controllers/HomeController.cs#L50

{
    e.CallbackData = urlResolver.ResolveClientUrl(resultFilePath);
}

asp-net-mvc-grid-use-upload-control-in-batch-edit-mode/CS/Sample/Controllers/HomeController.cs#L32

var name = e.UploadedFile.FileName;
e.CallbackData = name;

VB.NET

asp-net-mvc-grid-upload-excel-file-using-upload-control-and-display-data-in-grid/VB/T449148_VB/Controllers/HomeController.vb#L45

    e.UploadedFile.SaveAs(resultFilePath)
    e.CallbackData = resultFilePath
End If

asp-net-mvc-grid-upload-and-display-excel-file/VB/UploadControlApplication/Controllers/HomeController.vb#L36

If urlResolver IsNot Nothing Then
    e.CallbackData = urlResolver.ResolveClientUrl(resultFilePath)
End If

asp-net-mvc-grid-use-upload-control-in-batch-edit-mode/VB/Sample/Controllers/HomeController.vb#L34

Dim name = e.UploadedFile.FileName
e.CallbackData = name