I'm creating a WPF desktop client for work, and need to get data from a website using it's API.

This websites API requires a POST request in order to get data instead of a GET. This is a security feature as far as I can tell.

I cannot figure out how to format my request as most documentation is for application/json requests, but I need to POST my request using application/x-www-form-urlencoded .

The API will then respond in JSON format with the requested data which I will need to parse and use.

Here is what the websites limited documentation says:

API Request Format Our REST API is based on open standards, so you can use any web development language to access the API.

To make a request, you'll make an HTTPS POST to the applicable endpoint URL.

For example: https://app.agencybloc.com/api/v1/individuals/search

No parameters should be in the URL or querystring. The body of the request must contain the security credentials, as well as the method-specific parameters.

Note: The responses from the API are in JSON format as described in the method descriptions, but you do not POST JSON-formatted requests. They must be in application/x-www-form-urlencoded format per the above.

Here is what I need to POST to the site:

Host: https://app.agencybloc.com/api/v1/individuals/search
Cache-Control: no-cache
Content-Type: application/x-www-form-urlencoded

sid=mySID&key=myKey&updatedDTM=09/20/2021

And here is my code so far.

    public class tdate
    {
        public string updatedDTM { get; set; }
    }

    public class APIHelper
    {

        public void Main(string[] args)
        {

            HttpClient client = new HttpClient();

            HttpContent content = new FormUrlEncodedContent(
                new List<KeyValuePair<string, string>>()
                );

            content.Headers.ContentType = new MediaTypeHeaderValue("application/x--www-form-urlencoded");
            content.Headers.ContentType.CharSet = "UTF-8";
            content = "sid=mySID&key=myKey&updatedDTM=09/20/2021";
            client.DefaultRequestHeaders.ExpectContinue = false;
            client.BaseAddress = new Uri(https://app.agencybloc.com/api/v1/individuals/search/); 

        }
    }

I feel like I'm way off here. I have no clue how to even finish the POST request properly. I can't seem to find any definitive documentation, and none of the other questions about this topic make sense to me (as a relative newb in C#).

for the rest of the project I will have to parse the JSON response and make a second POST request using that data for even more data.

Let me know if I need to provide any more of my code, or any other details.

Thank you for any help.

EDIT: Got this to work.

Here's the Method:

public static HttpResponseMessage BlocCall()
        {

            HttpClient client = new HttpClient();

            var dict = new Dictionary<string, string>();
            dict.Add("sid", "MyID");
            dict.Add("key", "MyKey");
            dict.Add("lastName", "Heine");

            var req = new HttpRequestMessage(HttpMethod.Post, "https://app.agencybloc.com/api/v1/individuals/search/") { Content = new FormUrlEncodedContent(dict) };
            var res = client.SendAsync(req).Result;
            
            Newtonsoft.Json.JsonConvert.SerializeObject(res, Formatting.Indented);
            Trace.WriteLine(res);
            return res;
        }

And here is where it is called on Button Click:

private void Button_Click(object sender, RoutedEventArgs e)
        {
            APIHelper.BlocCall();
      
        }

CodePudding user response：

You can check something similar to this.

        HttpClient client = new HttpClient();

        var dict = new Dictionary<string, string>();
        dict.Add("sid", "mySID");
        dict.Add("key", "myKey");
        dict.Add("updatedDTM", "09/20/2021");

        var req = new HttpRequestMessage(HttpMethod.Post, "https://app.agencybloc.com/api/v1/individuals/search/") { Content = new FormUrlEncodedContent(dict) };
        var res =  client.SendAsync(req).Result;