About calling web api

Question

How to call web api, such as Window.alert and FileReader, in Razor components using c# instead of js?
Further, is it possible to thoroughly use c # instead of js in Blazor projects?

Answer 1

Hi @李畋岷 ,

How to call web api, such as Window.alert and FileReader, in Razor components using c# instead of js?

To the Window.Alert, if you want to show the alert, confirm or prompt dialog in Asp.net core Blazor application, you need to use the JSRuntime instance.

Refer to the following sample code:

The result is like this:

More detail information, refer to Call JavaScript functions from .NET methods in ASP.NET Core Blazor.

For the FileReader, if you want to upload file in Asp.net core Blazor application, you can use the InputFile component to read browser file data into .NET code, see ASP.NET Core Blazor file uploads.

Further, is it possible to thoroughly use c # instead of js in Blazor projects?

Not sure which effect you want to achieve, but you can check the ASP.NET Core Blazor event handling, if using the event handling can achieve the same behavior, then there is no need to use JS.

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Best regards,
Dillion

Answer 2

Blazor code either runs on the server, or in the WASM sandbox depending on project type. This means it has no direct access to the browser dom, files, or network. JavaScript interop is required.

You can code only in C#, if you can find blazor wrappers for the JavaScript interop you need to call. These would typically be 3rd party nuget packages.