I want to code an auto bot for an online game (tribalwars.net). I'm learning C# in school, but haven't covered networking yet.
Is it possible to make HTTP POSTs though C#? Can anyone provide an example?
Trivial with System.Net.WebClient:
using(WebClient client = new WebClient()) {
string responseString = client.UploadString(address, requestString);
}
There is also:
UploadData - binary (byte[])
UploadFile - from a file
UploadValues - name/value pairs (like a form)
You can use System.Net.HttpWebRequest:
Request
HttpWebRequest request= (HttpWebRequest)WebRequest.Create(url);
request.ContentType="application/x-www-form-urlencoded";
request.Method = "POST";
request.KeepAlive = true;
using (Stream requestStream = request.GetRequestStream())
{
requestStream.Write(BytePost,0,BytePost.Length);
requestStream.Close();
}
Response
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
using(StreamReader sr = new StreamReader(response.GetResponseStream()))
{
responseString = sr.ReadToEnd();
}
Here's a good example. You want to use the WebRequest class in C#, which will make this easy.
I understand this is old question, but posting this for someone looking for quick example on how to send Http Post request with json body in latest .NET (Core 5), using HttpClient (part of System.Net.Http namespace). Example:
//Initialise httpClient, preferably static in some common or util class.
public class Common
{
public static HttpClient HttpClient => new HttpClient
{
BaseAddress = new Uri("https://example.com")
};
}
public class User
{
//Function, where you want to post data to api
public void CreateUser(User user)
{
try
{
//Set path to api
var apiUrl = "/api/users";
//Initialize Json body to be sent with request. Import namespaces Newtonsoft.Json and Newtonsoft.Json.Linq, to use JsonConvert and JObject.
var jObj = JObject.Parse(JsonConvert.SerializeObject(user));
var jsonBody = new StringContent(jObj.ToString(), Encoding.UTF8, "application/json");
//Initialize the http request message, and attach json body to it
var request = new HttpRequestMessage(HttpMethod.Post, apiUrl)
{
Content = jsonBody
};
// If you want to send headers like auth token, keys, etc then attach it to request header
var apiKey = "qwerty";
request.Headers.Add("api-key", apiKey);
//Get the response
using var response = Common.HttpClient.Send(request);
//EnsureSuccessStatusCode() checks if response is successful, else will throw an exception
response.EnsureSuccessStatusCode();
}
catch (System.Exception ex)
{
//handle exception
}
}
}
Why is HttpClient static or recommended to be instantiated once per application:
HttpClient is intended to be instantiated once and re-used throughout
the life of an application. Instantiating an HttpClient class for
every request will exhaust the number of sockets available under heavy
loads. This will result in SocketException errors.
HttpClient class has async methods too. More info on HttpClient class: https://learn.microsoft.com/en-us/dotnet/api/system.net.http.httpclient?view=net-5.0
Related
I want to download data of this website into a json file but as I am quite new to coding with C# I cant manage to get the data. I want to get Data of https://discosweb.esoc.esa.int/api/objects the authorization via token works but I dont know how I can send a request so the server gives me a json back and I cant find a solution online. I cant give you a screenshot of the API because you have to be logged in to see it. Plz ask me for detailed information if you can help me. Thank you realy for trying.
The code I want to run is here.
class Program
{
static HttpClient client = new HttpClient();
static void Main(string[] args)
{
client.BaseAddress = new Uri("https://discosweb.esoc.esa.int");
client.DefaultRequestHeaders.Accept.Clear();
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/vnd.api+json"));
client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("my_token");
var httpRequest = (HttpWebRequest)WebRequest.Create(client.BaseAddress);
var httpResponse = (HttpWebResponse)httpRequest.GetResponse();
using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
{
var streamReaderResult = streamReader.ReadToEnd();
}
Console.WriteLine("Status https://discosweb.esoc.esa.int : " + httpResponse.StatusCode);
}
}
Try this
var url = "https://discosweb.esoc.esa.int/api/objects";
var httpRequest = (HttpWebRequest)WebRequest.Create(url);
httpRequest.Method = "POST";
httpRequest.Headers["Authorization"] = "Basic XXXx";
httpRequest.ContentType = "";
httpRequest.Headers["Content-Length"] = "0";
var httpResponse = (HttpWebResponse)httpRequest.GetResponse();
using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
{
var result = streamReader.ReadToEnd();
}
Console.WriteLine(httpResponse.StatusCode);
Where XXXx is user:password in base64.
Here is a basic implementation for making that API call to get the JSON result. You will need to parse that JSON into something other than a string but I'll assume you can handle that part.
This uses System.Net.HttpClient which is the modern HTTP api provided by .NET. Its operations are async so hopefully your code is or can be written to properly await async operations.
//Someplace convenient, create a shared HttpClient to avoid
//creating and disposing for each request.
HttpClient client = new HttpClient();
string data = await GetObjects(client);
//Example implementation
public async Task<string> GetObjects(HttpClient client)
{
string url = "https://discosweb.esoc.esa.int/api/objects";
using (HttpRequestMessage msg = new HttpRequestMessage(HttpMethod.Get, url))
{
msg.Headers.Authorization =
new System.Net.Http.Headers.AuthenticationHeaderValue("Bearer", "your personal access token here");
using (var result = await client.SendAsync(msg))
{
string content = await result.Content.ReadAsStringAsync();
return content;
}
}
}
While I may be a month late, I've actually developed an SDK for this particular API.
So, if you use this SDK it's pretty simple to do what you want. You can essentially forget about handling anything HTTP related, my SDK abstracts all of that away.
For example, to fetch Sputnik's data (which has an ID of 1) you'd run.
HttpClient innerClient = new();
innerClient.BaseAddress = "https://discosweb.esoc.esa.int/api/"
innerClient.DefaultRequestHeaders.Authorization = new("bearer", yourApiKey);
DiscosClient client = new();
DiscosObject sputnik = await client.GetSingle<DiscosObject>("1");
If you're using ASP.NET, there's a set of DI extensions that can actually set it all up for you, so you can skip the first three lines.
If you do choose to use it, please let me know, as it would be nice knowing my SDK is getting some use. If you have any issues, please just reach out through the GitHub issues page and I'll try to help!
I am completely new to this, I didn't even know about SOAP let alone WSDL before this, but here we go. My task is to parse some username information from a JSON API, and then send this information back via a SOAP message with WSDL.
I have the first part (for now I have the username just written in the console), I have all usernames.
Code so far:
static void Main(string[] args)
{
Uri apiUri = new Uri("https://xxxxxxxxxxxx.com/services/comex/v2/uman/users");
WebRequest webRequest = HttpWebRequest.Create(apiUri);
HttpWebRequest httpWebRequest = (HttpWebRequest)webRequest;
NetworkCredential networkCredentials = new NetworkCredential("xxxx", "xxxx");
CredentialCache myCredentialCache = new CredentialCache();
myCredentialCache.Add(apiUri, "Basic", networkCredentials);
httpWebRequest.PreAuthenticate = true;
httpWebRequest.Credentials = myCredentialCache;
WebResponse webResponse = webRequest.GetResponse();
Stream responseStream = webResponse.GetResponseStream();
StreamReader streamReader = new StreamReader(responseStream, Encoding.Default);
string serializedJson = streamReader.ReadToEnd();
DeserializedJson deserializedJson = JsonConvert.DeserializeObject<DeserializedJson>(serializedJson);
foreach (var row in deserializedJson.result)
{
Console.WriteLine(row.usern);
}
responseStream.Close();
webResponse.Close();
}
public class Result
{
public string usern { get; set; }
}
public class DeserializedJson
{
public List<Result> result { get; set; }
}
I have the WSDL file as a separate file, which I was able to add as a service reference to my project.
I am provided with a url "https://xxxxxxxx.com/Services/Wdx/Wdx.svc/apikey" and an API-key. I am really unsure what to do with these information.
Do I send a SOAP request and include the api key in the body? What about the data package, how do I include the 4 usernames as an XML?
I'm really looking for some general information, while I'm browsing dozens of other sources about how SOAP works as well, but it's really tough to wrap my head around in such a short time (1 day)
Any advice is highly appreciated.
I have an api
http://cbastest.cadvilpos.com/module/posmodule/customapi
with parameters
{
"action":4,
"device_token": "3e8ea119a90ee6d2",
"key":"9475962085b3a1b8c475d52.95782804",
"shop":1,
"language":1
}
This is working fine in postman. But when I try to connect from c# project its showing an error {"success":0,"error":"Missing the action parameter."}. Please give a working C# code to get the json result.
The code I tried:
var request = (HttpWebRequest)WebRequest.Create("http://cbastest.cadvilpos.com/module/posmodule/customapi");
var postData = "{ 'action':'4', 'device_token':'3e8ea119a90ee6d2','key':'9475962085b3a1b8c475d52.95782804','shop':'1','language':'1'}";
var data = Encoding.ASCII.GetBytes(postData);
request.Method = "POST";
request.ContentType = "application/json";
request.ContentLength = data.Length;
using (var stream = request.GetRequestStream())
{
stream.Write(data, 0, data.Length);
}
var response2 = (HttpWebResponse)request.GetResponse();
var responseString = new StreamReader(response2.GetResponseStream()).ReadToEnd();
You don't need to use a raw HttpWebRequest object to make an HTTP call. HttpClient was introduced in 2012 to allow easy asynchronous HTTP calls.
You could do something as simple as :
var content=new StringContent(postData,Encoding.UTF8, "application/json");
HttpResponseMessage response=await httpClient.PostAsync(url,content);
//Now process the response
if (response.IsSuccessCode)
{
var body=await response.Content.ReadAsStringAsync();
var responseDTO=JsonConvert.DeserializeObject<MyDTO>(body);
}
Instead of building a JSON string by hand you could use a strongly typed class or an anonymous object and serialize it to JSON with JSON.NET :
var data=new {
action=4,
device_token="3e8ea119a90ee6d2",
key = "9475962085b3a1b8c475d52.95782804",
shop=1,
language=1
};
var postData=JsonConvert.SerializeObject(data);
var content=new StringContent(postData,Encoding.UTF8, "application/json");
var response=await httpClient.PostAsync(url,content);
...
You can read a response body in one go as a string, using ReadAsStringAsync or you can get the response stream with ReadAsStreamAsync. You could copy the response data directly to another stream, eg a file or memory stream with HttpContent.CopyToAsync
Check Call a Web API from a .NET Client for more examples. Despite the title, the examples work to call any HTTP/REST API.
The Microsoft.AspNet.WebApi.Client package mentioned in that article is another thing that applies to any call, not just calls to ASP.NET Web API. The extension method PostAsJsonAsync for example, combines serializing and posting a request to a url. Using it, posting the action DTO could be reduced to a single line:
var data=new {
action=4,
device_token="3e8ea119a90ee6d2",
key = "9475962085b3a1b8c475d52.95782804",
shop=1,
language=1
};
var response=await httpClient.PostAsJsonAsync(url,data);
There is a button in Postman that will generate code for the currently defined request. The link is here:
And this is what the code looks like. You'll need to pull in RestSharp from Nuget
Currently trying to do a Get request as part of a c# program. The request works fine on Postman as it uses a header for authorization. However I cannot get the code working for the program to use this header correctly in its Get request. I've had a good look around and tried various bits of code I've found but haven't managed to resolve it so any help would be appreciated!
public string Connect()
{
using (WebClient wc = new WebClient())
{
string URI = "myURL.com";
wc.Headers.Add("Content-Type", "text");
wc.Headers[HttpRequestHeader.Authorization] = "Bearer OEMwNjI2ODQtMTc3OC00RkIxLTgyN0YtNzEzRkE5NzY3RTc3";//this is the entry code/key
string HtmlResult = wc.DownloadString(URI);
return HtmlResult;
}
}
Above is one method inside the class.
Below is another attempt which is an extension method that gets passed the URL:
public static string GetXml(this string destinationUrl)
{
HttpWebRequest request =
(HttpWebRequest)WebRequest.Create(destinationUrl);
request.Method = "GET";
request.Headers[HttpRequestHeader.Authorization] = "Bearer
OEMwNjI2ODQtMTc3OC00RkIxLTgyN0YtNzEzRkE5NzY3RTc3";
HttpWebResponse response;
response = (HttpWebResponse)request.GetResponse();
if (response.StatusCode == HttpStatusCode.OK)
{
Stream responseStream = response.GetResponseStream();
string responseStr = new
StreamReader(responseStream).ReadToEnd();
return responseStr;
}
else
{
Console.Write(String.Format("{0}({1})",
response.StatusDescription, response.StatusCode));
}
return null;
}
Might I recommend the very handy RestSharp package (find it on Nuget).
It turns your current code into something like
public string Connect()
{
var client = new RestClient();
var request = new RestRequest("myURL.com", Method.GET);
request.AddParameter("Authorization", "Bearer OEMwNjI2ODQtMTc3OC00RkIxLTgyN0YtNzEzRkE5NzY3RTc3");
var response = client.Execute(request);
return response.Content;
}
It's much more succinct and easier to use (in my opinion) and thus lessens the likelihood of passing in or using incorrect methods.
If you're still having issues getting data back/connecting. Then using PostMan click Code in the upper right of PostMan and select the C# (RestSharp) option. Whatever is generated there matches exactly what PostMan is sending. Copy that over and you should get data back that matches your PostMan request.
I am beginner and creating winform application. In which i have to use API for Simple CRUD operation. My client had shared API with me and asked to send data in form of JSON.
API : http://blabla.com/blabla/api/login-valida
KEY : "HelloWorld"
Value : { "email": "user#gmail.com","password": "123456","time": "2015-09-22 10:15:20"}
Response : Login_id
How can i convert data to JSON, call API using POST method and get response?
EDIT
Somewhere on stackoverflow i found this solution
public static void POST(string url, string jsonContent)
{
url="blabla.com/api/blala" + url;
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(baseURL);
request.Method = "POST";
System.Text.UTF8Encoding encoding = new System.Text.UTF8Encoding();
Byte[] byteArray = encoding.GetBytes(jsonContent);
request.ContentLength = byteArray.Length;
request.ContentType = #"application/json";
using (Stream dataStream = request.GetRequestStream())
{
dataStream.Write(byteArray, 0, byteArray.Length);
}
long length = 0;
try
{
using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
{
length = response.ContentLength;
}
}
catch
{
throw;
}
}
//on my login button click
private void btnLogin_Click(object sender, EventArgs e)
{
CallAPI.POST("login-validate", "{ \"email\":" + txtUserName.Text + " ,\"password\":" + txtPassword.Text + ",\"time\": " + DateTime.Now.ToString("yyyy-MM-dd h:mm tt") + "}");
}
I got exception that says "The remote server returned an error: (404) Not Found."
You can take a look at the following docs tutorial:
Call a Web API From a .NET Client
But as an answer, here I will share a quick and short a step by step guide about how to call and consume web API in Windows forms:
Install Package - Install the Microsoft.AspNet.WebApi.Client NuGet package (Web API Client Libraries).
Open Tools menu → NuGet Package Manager → Package Manager Console → In the Package Manager Console window, type the following command:
Install-Package Microsoft.AspNet.WebApi.Client
You can install package by right click on project and choosing Manage NuGet Packages as well.
Set up HttpClient - Create an instance of HttpClient and set up its BaseAddress and DefaultRequestHeaders. For example:
// In the class
static HttpClient client = new HttpClient();
// Put the following code where you want to initialize the class
// It can be the static constructor or a one-time initializer
client.BaseAddress = new Uri("http://localhost:4354/api/");
client.DefaultRequestHeaders.Accept.Clear();
client.DefaultRequestHeaders.Accept.Add(
new MediaTypeWithQualityHeaderValue("application/json"));
Send Request - To send the requests, you can use the following methods of the HttpClient:
GET: GetAsync, GetStringAsync, GetByteArrayAsync, GetStreamAsync
POST: PostAsync, PostAsJsonAsync, PostAsXmlAsync
PUT: PutAsync, PutAsJsonAsync, PutAsXmlAsync
DELETE: DeleteAsync
Another HTTP method: Send
Note: To set the URL of the request for the methods, keep in mind, since you have specified the base URL when you defined the client, then here for these methods, just pass path, route values and query strings, for example:
// Assuming http://localhost:4354/api/ as BaseAddress
var response = await client.GetAsync("products");
or
// Assuming http://localhost:4354/api/ as BaseAddress
var product = new Product() { Name = "P1", Price = 100, Category = "C1" };
var response = await client.PostAsJsonAsync("products", product);
Get the Response
To get the response, if you have used methods like GetStringAsync, then you have the response as string and it's enough to parse the response. If the response is a Json content which you know, you can easily use JsonConvert class of Newtonsoft.Json package to parse it. For example:
// Assuming http://localhost:4354/api/ as BaseAddress
var response = await client.GetStringAsync("product");
var data = JsonConvert.DeserializeObject<List<Product>>(response);
this.productBindingSource.DataSource = data;
If you have used methods like GetAsync or PostAsJsonAsync and you have an HttpResponseMessage then you can use ReadAsAsync, ReadAsByteArrayAsync, ReadAsStreamAsync, `ReadAsStringAsync, for example:
// Assuming http://localhost:4354/api/ as BaseAddress
var response = await client.GetAsync("products");
var data = await response.Content.ReadAsAsync<IEnumerable<Product>>();
this.productBindingSource.DataSource = data;
Performance Tip
HttpClient is a type that is meant to be created once and then shared. So don't try to put it in a using block every time that you want to use it. Instead, create an instance of the class and share it through a static member. To read more about this, take a look at Improper Instantiation antipattern
Design Tip
Try to avoid mixing the Web API related code with your application logic. For example let's say you have a product Web API service. Then to use it, first define an IProductServieClient interface, then as an implementation put all the WEB API logic inside the ProductWebAPIClientService which you implement to contain codes to interact with WEB API. Your application should rely on IProductServieClient. (SOLID Principles, Dependency Inversion).
Just use the following library.
https://www.nuget.org/packages/RestSharp
GitHub Project: https://github.com/restsharp/RestSharp
Sample Code::
public Customer GetCustomerDetailsByCustomerId(int id)
{
var client = new RestClient("http://localhost:3000/Api/GetCustomerDetailsByCustomerId/" + id);
var request = new RestRequest(Method.GET);
request.AddHeader("X-Token-Key", "dsds-sdsdsds-swrwerfd-dfdfd");
IRestResponse response = client.Execute(request);
var content = response.Content; // raw content as string
dynamic json = JsonConvert.DeserializeObject(content);
JObject customerObjJson = json.CustomerObj;
var customerObj = customerObjJson.ToObject<Customer>();
return customerObj;
}
Use Json.Net to convert data into JSON
Use WebClient to POST data
Use This code:
var client = new HttpClient();
client.BaseAddress = new Uri("http://www.mywebsite.com");
var request = new HttpRequestMessage(HttpMethod.Post, "/path/to/post/to");
var keyValues = new List<KeyValuePair<string, string>>();
keyValues.Add(new KeyValuePair<string, string>("site", "http://www.google.com"));
keyValues.Add(new KeyValuePair<string, string>("content", "This is some content"));
request.Content = new FormUrlEncodedContent(keyValues);
var response = await client.SendAsync(request);
Here is another example using an online REST service (https://northwind.vercel.app) which allows interaction with Northwind API.
This example uses HttpClient and JsonConvert to get or post data. Here is a very quick example:
Install Newtonsoft.Json nuget package. And add the following using statements to your form:
using System.Net.Http;
using Newtonsoft.Json
Define an instance of the HttpClient, at class level:
private static HttpClient client = new HttpClient();
To send a GET request, for example getting list of all data:
var url = "https://northwind.vercel.app/api/categories";
var response = await client.GetAsync(url);
if (response.StatusCode == System.Net.HttpStatusCode.OK)
{
var content = await response.Content.ReadAsStringAsync();
var categories = JsonConvert.DeserializeObject<List<Category>>(content);
dataGridView1.DataSource = categories;
}
You can also use other overloads of Get, like GetStringAsync, GetStreamAsync, and etc. But GetAsync is a more generic method allowing you to get the status code as well.
To send a POST request, for example posting a new data:
var url = "https://northwind.vercel.app/api/categories";
var data = new Category() { Name = "Lorem", Description = "Ipsum" };
var jsonData = Newtonsoft.Json.JsonConvert.SerializeObject(data);
var requestContent = new StringContent(jsonData, Encoding.Unicode, "application/json");
var response = await client.PostAsync(url, requestContent);
if (response.StatusCode == System.Net.HttpStatusCode.Created)
{
var content = await response.Content.ReadAsStringAsync();
var createdCategory = JsonConvert.DeserializeObject<Category>(content);
MessageBox.Show(createdCategory.Id.ToString())
}
To learn more and see some best practices or see an example without JsonConvert, see my other post.