Tag Helper Basics

The core-upload Tag Helper renders a complete upload component. Use asp-* attributes to configure behavior declaratively.

What you should see: the Tag Helper form of the control: attributes on one element instead of a JavaScript configuration block, rendering the same uploader.

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<core-upload asp-upload-url="/api/upload/upload"
 asp-multiple="true"
 asp-progress="true"
 asp-drop-zone="true">
</core-upload>

Server-rendered configuration

The tag helper turns Razor attributes into the client configuration, so the options live in your view alongside the rest of the markup rather than in a script block. Values can come from the model, which is what makes per-user or per-record limits straightforward.

It still produces plain JavaScript

What ships to the browser is the same component the JavaScript API configures directly, so nothing is hidden from you: view source and the emitted CoreUpload.create(...) call shows exactly which options the attributes produced. That is also the quickest way to check whether an attribute did what you expected.