C# - Xamarin forms add custom header PATCH

Question

I'm using a REST full API, which needs a PATCH header... So in xamarin, you only have getasync, postasync, putasync and send async...

But I have no clue on how to add /make a PATCH async method (or even do such a request)

This is the code I currently have to be send via a patch

Folder add_list_to_folder = new Folder()
                    {
                        // revision is required, so we take the current revision and add one to it.
                        revision = folder_to_be_updated.revision += 1,
                        list_ids = arr_of_lists
                    };

Now, I think that needs to get seialized, so like this:

response = await client.PostAsync(url,
                    new StringContent(
                        JsonConvert.SerializeObject(add_list_to_folder),
                        Encoding.UTF8, "application/json"));

But that is a post, so how can I make an PATCH request?

score 2 · Accepted Answer · edited Nov 23 '17 at 21:10

You should be able to send a completely custom request with the HttpClient. Since PATCH isn't a very common verb, there isn't a shorthand for it.

From the top of my head, try something like this:

var method = new HttpMethod("PATCH");

var request = new HttpRequestMessage(method, url) {
    Content = new StringContent(
                    JsonConvert.SerializeObject(add_list_to_folder),
                    Encoding.UTF8, "application/json")
};

var response = await client.SendAsync(request);

If you have to use it at several places, it might be just as neat to wrap it in an extension method, like:

public static async Task<HttpResponseMessage> PatchAsync(this HttpClient client, Uri requestUri, HttpContent httpContent)
{
    // TODO add some error handling
    var method = new HttpMethod("PATCH");

    var request = new HttpRequestMessage(method, requestUri) {
        Content = httpContent
    };

    return await client.SendAsync(request);
}

Now you should be able to call it directly on your HttpClient like the post or get methods, i.e.:

var client = new HttpClient();
client.PatchAsync(url, new StringContent(
                    JsonConvert.SerializeObject(add_list_to_folder),
                    Encoding.UTF8, "application/json"));

C# - Xamarin forms add custom header PATCH

1 Answers1