Develop Reference

GraphQL request in C#

I'm a Unity developer tool and i want to post a GraphQL request with using System.Net.Http; (i don't want to use the GraphQL dll because there are compatibility problems).
But i have this error (got on the Debug.Log) :
POST body missing, invalid Content-Type, or JSON object has no keys.
My code :
static async Task<string> getEntityID(string path)
{
var values = new Dictionary<string, string>
{
{ "query", "query {topLevelEntityTypes {id}}" },
{ "variables", "{}" }
};
var content = new FormUrlEncodedContent(values);
var response = await client.PostAsync("http://localhost:4000/graphql", content);
var responseString = await response.Content.ReadAsStringAsync();
Debug.Log(responseString);
return responseString;
}
Thank you !

Solution by ProgrammingLlama :
static async Task<string> getEntityID(string path)
{
var myObject = new QueryJson();
myObject.query = "query {topLevelEntityTypes {id}}";
myObject.variables = "{}";
var response = await client.PostAsync("http://localhost:4000/graphql", new StringContent(Newtonsoft.Json.JsonConvert.SerializeObject(myObject), Encoding.UTF8, "application/json"));
var responseString = await response.Content.ReadAsStringAsync();
Debug.Log(responseString);
return responseString;
}
Class json
internal class QueryJson
{
public string query { get; set; }
public string variables { get; set; }
}

C#- http client response help request

I have the following code:
static async Task checkIMEI( double IMEI)
{
var client = new HttpClient();
var request = new HttpRequestMessage
{
Method = HttpMethod.Get,
RequestUri = new Uri("https://kelpom-imei-checker1.p.rapidapi.com/api?service=model&imei=" + IMEI.ToString() ),
Headers =
{
{ "X-RapidAPI-Host", "kelpom-imei-checker1.p.rapidapi.com" },
{ "X-RapidAPI-Key", "key" },
}
};
using (var response = await client.SendAsync(request))
{
response.EnsureSuccessStatusCode();
object result = await response.Content.ReadAsStringAsync();
MessageBox.Show("\n" + result);
}
}
Running this code I get the following
response
I would like to further break up this response and the individual data and assign it to a variable such as
string ModelNum= model_nb >> should show "SM-G891A"
String Brand = brand >> should show "Samsung Korea"
Your help would be appriciated.

first your Client is bad practice use this link HttpClientFactory Microsoft docs to refactor your client.
Then Create Class for your needed model for ex:
public class Mobile
{
public string ModelNum { get; set; }
public string Brand { get; set; }
}
then you should deserialize your result to your model:
var result = await response.Content.ReadAsStringAsync();
var model = JsonSerializer.Deserialize<Mobile>(result);

WebApi HttpPost not receiving the posted content from HttpClient

Web API:
I tried using [FormBody] and [FromForm] before the string stringcontent as well.
// POST api/<MAUserController>
[HttpPost("AuthenticateUser")]
public async Task<ActionResult<MAUser>> PostAsync(string stringcontent)
{
//stringcontent is null
}
Client Code:
List<KeyValuePair<string, string>> postParameters = new List<KeyValuePair<string, string>>();
postParameters.Add(new KeyValuePair<string, string>("Email", Email));
postParameters.Add(new KeyValuePair<string, string>("Password", Password));
var jsonString = JsonConvert.SerializeObject(postParameters);
var stringContent = new StringContent(jsonString, Encoding.UTF8, "application/json");
using (var httpClient = new HttpClient())
{
httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", tokenString);
//httpClient.DefaultRequestHeaders.Add("Email", Email);
//httpClient.DefaultRequestHeaders.Add("Password", Password);
using (var response = await httpClient.PostAsync(API_URL, stringContent))
{
if (response.IsSuccessStatusCode)
{
//Success code
}
else
{
//Handle unsuccessful here
}
}

You're posting structured data in JSON format from the client. So why is the API just trying to accept a plain string? That doesn't make a lot of sense.
You should make it accept a model object with the correct structure, instead. ASP.NET will take care of binding the JSON properties to the model properties. However, you should also simplify the postParameters in the client as well - you're over-complicating the structure.
e.g.
Client:
var postParameters = new { Email = "abc#example.com", Password = "xyz" };
Server:
public async Task<ActionResult<MAUser>> PostAsync([FromBody] UserCredentials credentials)
{
}
where UserCredentials is a DTO class like this:
public class UserCredentials
{
public string Email { get; set; }
public string Password { get; set; }
}

ok so when using content type you are basically telling the receiving API how to parse the request payload and so by telling it application/json the framework is trying to parse the payload from JSON to an object and assign it to your parameter ( not really since you need to add an attribute [FromBody] ) but it can not do it since you are expecting a string, so either change your content type or change your parameter type ( i would suggest your parameter type ) .

How do I retrieve and use data I get with Http GET Requests in c#

So I am trying to use GET requests with c# but nothing is really working out.
I wanted to use the site https://covid19.mathdro.id/api as a test to see if I can get the info out of there and use it in a windows form. But I can't seem to figure out how. The only guides I found weren't really that helpful and it just confused me more. Would anyone be able to help me out?
I have tried to use the HttpClient with JSON.net but I get confused in it.
Been trying for the past 2 hours since I never dealt with HTTP GET Requests in c# other than with Python.

Install the 'Newtonsoft.Json' nuget package.
async Task<JToken> GetREST(string uri)
{
using (var client = new HttpClient())
{
client.BaseAddress = new Uri(uri);
client.DefaultRequestHeaders.Accept.Clear();
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
// HTTP GET
HttpResponseMessage response = await client.GetAsync("");
if (response.IsSuccessStatusCode)
{
var jsonData = await response.Content.ReadAsStringAsync();
return JToken.Parse(jsonData);
}
}
return null;
}
async private void button1_Click(object sender, EventArgs e)
{
var jObj = await GetREST("https://covid19.mathdro.id/api");
var confirmed = jObj["confirmed"];
Console.WriteLine("Confirmed:" + confirmed["value"]);
var confirmedJSON = await GetREST(confirmed["detail"].ToString());
Console.WriteLine(confirmedJSON);
}

In addition to the accepted answer, you can always work with the data as objects by deserializing - I prefer this method over using JToken etc as it tends to be very easy to work with the objects (there's often less boilerplate to pull bits of data from the response).
public async Task<CovidData> GetCovidData(string uri)
{
using (var client = new HttpClient())
{
client.BaseAddress = new Uri(uri);
client.DefaultRequestHeaders.Accept.Clear();
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
HttpResponseMessage response = await client.GetAsync("");
if (response.IsSuccessStatusCode)
{
var jsonData = await response.Content.ReadAsStringAsync();
return JsonConvert.DeserializeObject<CovidData>(jsonData);
}
}
return null;
}
The objects you'd deserialize to would look like this:
public class CovidData
{
public ValueDetailPair Confirmed { get; set; }
public ValueDetailPair Recovered { get; set; }
public ValueDetailPair Deaths { get; set; }
}
public class ValueDetailPair
{
public int Value { get; set; }
// If you need the link to the detail it would be deserialized to this string member
public string Detail { get; set; }
}
It really does depend on preference and your use case though.
example:
var data = await GetCovidData("https://covid19.mathdro.id/api");
Console.WriteLine(data.Confirmed.Value);
Console.WriteLine(data.Confirmed.Detail);
Console.WriteLine(data.Recovered.Value);

How to post a long string containing XML to Web API

I'm trying to post a long string (containing XML) to my Web API controller, but I'm failing miserablely.
The following works if TextAsXml is short, but when TextAsXml is long it fails "Invalid URI: The Uri string is too long.", which is understandable.
// Client code
using (var client = new HttpClient())
{
var requestUri = "http://localhost:49528/api/some";
var content = new FormUrlEncodedContent(new[]
{
new KeyValuePair<string, string>("Author", "John Doe"),
new KeyValuePair<string, string>("TextAsXml", "<?xml version=\"1.0\" encoding=\"UTF-8\"?><note><to>Tove</to><from>Jani</from><heading>Reminder</heading><body>Don't forget me this weekend!</body></note>")
});
var response = client.PostAsync(requestUri, content).Result;
response.EnsureSuccessStatusCode();
}
// Controller code
public HttpResponseMessage Post(SomeModel someModel)
{
// ...
return Request.CreateResponse(HttpStatusCode.OK);
}
public class SomeModel
{
public string Author { get; set; }
public string TextAsXml { get; set; }
}
How do I get the above code to work when TextAsXml is long? I tried playing around with StringContent and MultipartContent, but couldn't get it to work.
// This results in 500 Internal server error.
using (var client = new HttpClient())
{
var requestUri = "http://localhost:49528/api/some";
var textAsXml = File.ReadAllText("Note.xml");
var content = new MultipartFormDataContent();
content.Add(new StringContent("John Doe"), "Author");
content.Add(new StringContent(textAsXml), "TextAsXml");
var response = client.PostAsync(requestUri, content).Result;
response.EnsureSuccessStatusCode();
}

Send the XML as content without Uri encoding.