Legacy Uploader

Uploader is the main compatibility wrapper for older 4.x single-file and multi-file upload pages.

It is built on top of AjaxFileUpload, so the runtime is modern even though the public API is legacy-friendly.

Typical markup

<%@ Register Assembly="AjaxUploader" Namespace="CuteWebUI" TagPrefix="CuteWebUI" %>

<CuteWebUI:Uploader ID="Uploader1" runat="server"
    InsertText="Upload files"
    MultipleFilesUpload="true"
    ManualStartUpload="false"
    ShowProgressBar="true"
    ShowQueueTable="true"
    OnFileUploaded="Uploader1_FileUploaded"
    OnUploadCompleted="Uploader1_UploadCompleted">
    <ValidateOption AllowedFileExtensions="jpg,png,pdf,zip" MaxSizeKB="10240" />
</CuteWebUI:Uploader>

Typical code-behind

protected void Uploader1_FileUploaded(object sender, CuteWebUI.UploaderEventArgs e)
{
    var targetFolder = Server.MapPath("~/App_Data/Processed");
    System.IO.Directory.CreateDirectory(targetFolder);

    e.CopyTo(System.IO.Path.Combine(targetFolder, e.FileName));
}

protected void Uploader1_UploadCompleted(object sender, CuteWebUI.UploaderEventArgs[] files)
{
    lblStatus.Text = "Uploaded " + files.Length + " file(s).";
}

Most-used members

Legacy member	What it does
InsertText	Browse button caption
MultipleFilesUpload	Enables multi-file selection
ManualStartUpload	Switches between automatic and manual upload start
ShowProgressBar	Shows the progress UI
ShowQueueTable	Shows the uploaded file queue
MaxFilesLimit	Limits the number of selected files
ValidateOption	Holds size, extension, MIME, and regex validation rules
FileUploaded	Fires for each uploaded file
UploadCompleted	Fires after the current batch completes

Automatic postback (4.x parity)

Like the 4.x control, Uploader posts back automatically when the upload batch finishes, so FileUploaded and UploadCompleted fire on the server with no submit button and no extra wiring. This is on by default for the legacy control. If a normal submit button already drives your form and you do not want the automatic postback, set AutoPostBack="false" in the markup.

Important compatibility note

Properties such as UploadType, FlashLoadMode, and other plugin-era flags are kept for source compatibility. They still compile, but the v5 runtime remains HTML5-based.

When to modernize

If you are building a new page instead of upgrading an old one, prefer AjaxFileUpload.