How to build a query string for a URL in C#?

Question

A common task when calling web resources from a code is building a query string to including all the necessary parameters. While by all means no rocket science, there are so

Answer 1

Flurl [disclosure: I'm the author] supports building query strings via anonymous objects (among other ways):

var url = "http://www.some-api.com".SetQueryParams(new
{
    api_key = ConfigurationManager.AppSettings["SomeApiKey"],
    max_results = 20,
    q = "Don't worry, I'll get encoded!"
});

The optional Flurl.Http companion lib allows you to do HTTP calls right off the same fluent call chain, extending it into a full-blown REST client:

T result = await "https://api.mysite.com"
    .AppendPathSegment("person")
    .SetQueryParams(new { ap_key = "my-key" })
    .WithOAuthBearerToken("MyToken")
    .PostJsonAsync(new { first_name = firstName, last_name = lastName })
    .ReceiveJson();

The full package is available on NuGet:

PM> Install-Package Flurl.Http

or just the stand-alone URL builder:

PM> Install-Package Flurl