Calling a web API from Blazor WebAssembly

Making calls to the web API from the Blazor app involves the same steps as doing so from Postman. We start by defining the endpoint to call, prepare the data to send with the request if needed, submit the request, and, finally, receive and process the response.

.NET has a built-in class called HttpClient, which is a rich class that provides all the functionality and configuration needed to send any type of request (GET, POST, PUT, PATCH, DELETE, and more) to a given web API.

Understanding FetchData component logic

All Blazor WebAssembly projects have a default page called FetchData in the Pages folder. The logic of this page is to make a GET request to download the content of a JSON file that lives in the wwwroot folder, and that content also represents weather forecast data. So, let’s analyze the code of the FetchData component so that we understand it better:

@page "/fetchdata"@inject HttpClient Http
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