Single File Upload

The simplest upload scenario: select one file and upload it. Restrict to specific file types and set a maximum size using tag helper attributes.

What you should see: pick a file and press the upload button — the queue row fills to 100% and turns green once the server has stored it.

Drag & drop files here, or paste from clipboard

<core-upload asp-upload-url="/api/upload/upload"
 asp-extensions=".jpg,.png,.gif,.pdf"
 asp-max-size="10MB"
 asp-progress="true">
</core-upload>

The ordinary case

One request per file, a size cap, an extension list. For a form attachment of a few megabytes this is the right shape — chunking adds server-side work that buys nothing at that size.

Two signals that it is time to move on

Files large enough that a dropped connection means starting over, or a body-size limit somewhere between the browser and your handler that you cannot raise. Both point at asp-chunked, and neither is worth pre-empting before it happens.