How to post data using HttpClient? - c#

I have got this HttpClient from Nuget.
When I want to get data I do it this way:
var response = await httpClient.GetAsync(url);
var data = await response.Content.ReadAsStringAsync();
But the problem is that I don't know how to post data?
I have to send a post request and send these values inside it: comment="hello world" and questionId = 1. these can be a class's properties, I don't know.
Update I don't know how to add those values to HttpContent as post method needs it. httClient.Post(string, HttpContent);

You need to use:
await client.PostAsync(uri, content);
Something like that:
var comment = "hello world";
var questionId = 1;
var formContent = new FormUrlEncodedContent(new[]
{
new KeyValuePair<string, string>("comment", comment),
new KeyValuePair<string, string>("questionId", questionId)
});
var myHttpClient = new HttpClient();
var response = await myHttpClient.PostAsync(uri.ToString(), formContent);
And if you need to get the response after post, you should use:
var stringContent = await response.Content.ReadAsStringAsync();

Try to use this:
using (var handler = new HttpClientHandler() { CookieContainer = new CookieContainer() })
{
using (var client = new HttpClient(handler) { BaseAddress = new Uri("site.com") })
{
//add parameters on request
var body = new List<KeyValuePair<string, string>>
{
new KeyValuePair<string, string>("test", "test"),
new KeyValuePair<string, string>("test1", "test1")
};
HttpRequestMessage request = new HttpRequestMessage(HttpMethod.Post, "site.com");
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/x-www-form-urlencoded; charset=UTF-8"));
client.DefaultRequestHeaders.Add("Upgrade-Insecure-Requests", "1");
client.DefaultRequestHeaders.Add("X-Requested-With", "XMLHttpRequest");
client.DefaultRequestHeaders.Add("X-MicrosoftAjax", "Delta=true");
//client.DefaultRequestHeaders.Add("Accept", "*/*");
client.Timeout = TimeSpan.FromMilliseconds(10000);
var res = await client.PostAsync("", new FormUrlEncodedContent(body));
if (res.IsSuccessStatusCode)
{
var exec = await res.Content.ReadAsStringAsync();
Console.WriteLine(exec);
}
}
}

Use UploadStringAsync method:
WebClient webClient = new WebClient();
webClient.UploadStringCompleted += (s, e) =>
{
if (e.Error != null)
{
//handle your error here
}
else
{
//post was successful, so do what you need to do here
}
};
webClient.UploadStringAsync(new Uri(yourUri), UriKind.Absolute), "POST", yourParameters);

Related

Postman form-data: How to program it inside a HttpRequestMessage?

I am doing a request through postman to a specific url but I set the form-data type in order to get data to the site like this:
Now I want to program this request inside C# but everything I tried so far is returning a 400 Bad Request response. This is what I tried:
public async Task<CheckAccessTokenModel> CheckAccessTokenAsync(string accessToken)
{
string uriString = "someurl";
var uri = new Uri(uriString);
try
{
using(var httpClient = new HttpClient())
{
var request = new HttpRequestMessage
{
Method = HttpMethod.Post,
RequestUri = uri
};
var ClientId = ConfigurationAccessor.Configuration["WebCredentials:ClientId"];
var Secret = ConfigurationAccessor.Configuration["WebCredentials:Secret"];
var authString = Convert.ToBase64String(Encoding.UTF8.GetBytes($"{ClientId}:{Secret}"));
request.Headers.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("Basic", authString);
MultipartFormDataContent content = new MultipartFormDataContent();
content.Add(new StringContent("token"), accessToken);
request.Content = content;
var response = await httpClient.SendAsync(request);
var checkTokenResponseData = await response.Content.ReadAsStringAsync();
//return new CheckAccessTokenModel { Active = true, Exp = 1647431224233 };
return JsonConvert.DeserializeObject<CheckAccessTokenModel>(checkTokenResponseData);
}
}
catch
{
return null;
}
}
I am doing it with the MultipartFormDataContent Object as suggested by many others here but it still won't work.
What can be the problem here?
EDIT: Wrong picture replaced
You can simply
request.Content = new StringContent($"token={accessToken}");
With form data I think it's something like this:
var data = new Dictionary<string, string>
{
{"token", acccessToken}
};
using var content = new FormUrlEncodedContent(data);
request.Content = content;

How to send a json file with HttpClient in C#?

I'm trying send a JSON file with postman and it's working. But when I'm trying to send the same contents via HttpClient it's not working.
System.IO.File.WriteAllText(dirName + "\\importproduct.json", jsonitems);
var fileByteArray = File.ReadAllBytes(dirName + "\\importproduct.json");
using (var _client = new HttpClient())
{
using (var content = new MultipartFormDataContent())
{
content.Add(new StreamContent(new MemoryStream(fileByteArray)), "file");
var url = $"{firmInfo.ServiceUrl}/product/api/products/import";
_client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", bearer_token.id_token);
var response = _client.PostAsJsonAsync(url, content).Result;
var result = response.Content.ReadAsStringAsync().Result;
}
}
PostMan:
Instead of using PostAsJsonAsync(); method you should use PostAsync(); So your code should be looking something like that
using (var _client = new HttpClient())
{
using (var content = new MultipartFormDataContent())
{
content.Add(new StreamContent(new MemoryStream(fileByteArray)), "file");
var url = $"{firmInfo.ServiceUrl}/product/api/products/import";
_client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", bearer_token.id_token);
var response = _client.PostAsync(url, content).Result;
var result = response.Content.ReadAsStringAsync().Result;
}
}
PostAsJsonAsync method is a generic method, it expects as the second parameter the object that will be serialized and sent in the POST body.
var obj = JsonConvert.DeserializeObject<SomeModelClass>(jsonString);
var response = await _client.PostAsJsonAsync(url, obj).Result;
This is based on efecetir's post above. It works for me. BTW, I also upvoted his post.
My issue was I needed to set the content type at the content-based level.
var fileByteArray = File.ReadAllBytes(filePath);
HttpContent bytesContent = new ByteArrayContent(fileByteArray);
using (var httpClient = new HttpClient())
using (var formData = new MultipartFormDataContent())
{
var RequestUri = new Uri($"http://whatever.com/");
//client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", bearer_token.id_token);
formData.Headers.Add("super-secret-key", "blah");
bytesContent.Headers.ContentType = System.Net.Http.Headers.MediaTypeHeaderValue.Parse("application/json");
//httpClient.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json")); //("multipart/form-data")); // Not needed
formData.Add(bytesContent, "file", "blah.json");
var response = httpClient.PostAsync(RequestUri, formData).Result;
return await HandleResponse(response);
}
Thanks for your comments.
I fixed it and convert my codes as below. Now it's working and much more clean.
HttpContent bytesContent = new ByteArrayContent(fileByteArray);
using (var client = new HttpClient())
using (var formData = new MultipartFormDataContent())
{
var url = $"{firmInfo.ServiceUrl}/product/api/products/import";
client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", bearer_token.id_token);
formData.Add(bytesContent, "file", "importproduct.json");
var response = client.PostAsync(url, formData).Result;
var result = response.Content.ReadAsStringAsync().Result;
}
Here's code I'm using to post form information and a file
using (var httpClient = new HttpClient())
{
var surveyBytes = ConvertToByteArray(surveyResponse);
httpClient.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
var byteArrayContent = new ByteArrayContent(surveyBytes);
byteArrayContent.Headers.ContentType = MediaTypeHeaderValue.Parse("text/csv");
var url = $"{firmInfo.ServiceUrl}/product/api/products/import";
var response = await httpClient.PostAsync(url , new MultipartFormDataContent
{
{byteArrayContent, "\"file\"", dirName + "\\importproduct.json"}
});
return response;
}
This is for .net 4.5.

How to POST using HTTPclient content type = application/x-www-form-urlencoded

I am currently developing a wp8.1 application C#, i have managed to perform a POST method in json to my api by creating a json object (bm) from textbox.texts.
here is my code below. How do i take the same textbox.text and POST them as a content type = application/x-www-form-urlencoded. whats the code for that?
Profile bm = new Profile();
bm.first_name = Names.Text;
bm.surname = surname.Text;
string json = JsonConvert.SerializeObject(bm);
MessageDialog messageDialog = new MessageDialog(json);//Text should not be empty
await messageDialog.ShowAsync();
HttpClient client = new HttpClient();
client.DefaultRequestHeaders.Clear();
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
client.DefaultRequestHeaders.TryAddWithoutValidation("Content-Type", "application/json");
byte[] messageBytes = Encoding.UTF8.GetBytes(json);
var content = new ByteArrayContent(messageBytes);
content.Headers.ContentType = new MediaTypeHeaderValue("application/json");
var response = client.PostAsync("myapiurl", content).Result;
var nvc = new List<KeyValuePair<string, string>>();
nvc.Add(new KeyValuePair<string, string>("Input1", "TEST2"));
nvc.Add(new KeyValuePair<string, string>("Input2", "TEST2"));
var client = new HttpClient();
var req = new HttpRequestMessage(HttpMethod.Post, url) { Content = new FormUrlEncodedContent(nvc) };
var res = await client.SendAsync(req);
Or
var dict = new Dictionary<string, string>();
dict.Add("Input1", "TEST2");
dict.Add("Input2", "TEST2");
var client = new HttpClient();
var req = new HttpRequestMessage(HttpMethod.Post, url) { Content = new FormUrlEncodedContent(dict) };
var res = await client.SendAsync(req);
var params= new Dictionary<string, string>();
var url ="Please enter URLhere";
params.Add("key1", "value1");
params.Add("key2", "value2");
using (HttpClient client = new HttpClient())
{
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
HttpResponseMessage response = client.PostAsync(url, new FormUrlEncodedContent(params)).Result;
var token = response.Content.ReadAsStringAsync().Result;
}
//Get response as expected
The best solution for me is:
// Add key/value
var dict = new Dictionary<string, string>();
dict.Add("Content-Type", "application/x-www-form-urlencoded");
// Execute post method
using (var response = httpClient.PostAsync(path, new FormUrlEncodedContent(dict))){}
Another variant to POST this content type and which does not use a dictionary would be:
StringContent postData = new StringContent(JSON_CONTENT, Encoding.UTF8, "application/x-www-form-urlencoded");
using (HttpResponseMessage result = httpClient.PostAsync(url, postData).Result)
{
string resultJson = result.Content.ReadAsStringAsync().Result;
}

How to send a file and form data with HttpClient in C#

How can I send a file and form data with the HttpClient?
I have two ways to send a file or form data. But I want to send both like an HTML form. How can I do that? Thanks.
This is my code:
if (openFileDialog1.ShowDialog() == DialogResult.OK)
{
var client = new HttpClient();
var requestContent = new MultipartFormDataContent();
filename = openFileDialog1.FileName;
array = File.ReadAllBytes(filename);
var imageContent = new ByteArrayContent(array);
imageContent.Headers.ContentType = MediaTypeHeaderValue.Parse("audio/*");
requestContent.Add(imageContent, "audio", "audio.wav");
var values = new Dictionary<string, string>
{
{ "token", "b53b99534a137a71513548091271c44c" },
};
var content = new FormUrlEncodedContent(values);
requestContent.Add(content);
var response = await client.PostAsync("localhost", requestContent);
var responseString = await response.Content.ReadAsStringAsync();
txtbox.Text = responseString.ToString();
}
Here's code I'm using to post form information and a csv file
using (var httpClient = new HttpClient())
{
var surveyBytes = ConvertToByteArray(surveyResponse);
httpClient.DefaultRequestHeaders.Add("X-API-TOKEN", _apiToken);
httpClient.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
var byteArrayContent = new ByteArrayContent(surveyBytes);
byteArrayContent.Headers.ContentType = MediaTypeHeaderValue.Parse("text/csv");
var response = await httpClient.PostAsync(_importUrl, new MultipartFormDataContent
{
{new StringContent(surveyId), "\"surveyId\""},
{byteArrayContent, "\"file\"", "\"feedback.csv\""}
});
return response;
}
This is for .net 4.5.
Note the \" in the MultipartFormDataContent. There is a bug in MultipartFormDataContent.
In 4.5.1 MultipartFormDataContent wraps the data with the correct quotes.
Update: This link to the bug no longer works since the have retired Microsoft Connect.
Here's code I'm using a method to send file and data from console to API
static async Task uploaddocAsync()
{
MultipartFormDataContent form = new MultipartFormDataContent();
Dictionary<string, string> parameters = new Dictionary<string, string>();
//parameters.Add("username", user.Username);
//parameters.Add("FullName", FullName);
HttpContent DictionaryItems = new FormUrlEncodedContent(parameters);
form.Add(DictionaryItems, "model");
try
{
var stream = new FileStream(#"D:\10th.jpeg", FileMode.Open);
HttpClient client = new HttpClient();
client.BaseAddress = new Uri(#"http:\\xyz.in");
HttpContent content = new StringContent("");
content.Headers.ContentDisposition = new ContentDispositionHeaderValue("form-data")
{
Name = "uploadedFile1",
FileName = "uploadedFile1"
};
content = new StreamContent(stream);
form.Add(content, "uploadedFile1");
client.DefaultRequestHeaders.Add("Authorization", "Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.dsfdsfdsfdsfsdfkhjhjkhjk.vD056hXETFMXYxOaLZRwV7Ny1vj-tZySAWq6oybBr2w");
var response = client.PostAsync(#"\api\UploadDocuments\", form).Result;
var k = response.Content.ReadAsStringAsync().Result;
}
catch (Exception ex)
{
}
}

Post an image with HTTPClient but also some parameters on windows phone

I want to do a MultipartFormDataContent request. But I also want to pass a lot of params with it. When I'm just doing a post I do this:
public async Task<Webservice> inviteMembrs(List<KeyValuePair<string, string>> values)
{
String strUrl = String.Format("http://*****.com/nl/webservice/abc123/members/invite");
var http = new HttpClient();
var request = new HttpRequestMessage(HttpMethod.Post, new Uri(strUrl));
request.Content = new HttpFormUrlEncodedContent(values);
var result = await http.SendRequestAsync(request);
var data = new Webservice { Status = result.StatusCode };
if (result.StatusCode == Windows.Web.Http.HttpStatusCode.Ok && result.Content != null)
{
data.Data = await result.Content.ReadAsStringAsync();
Debug.WriteLine(data.Data);
}
return data;
}
This works perfect. But now I also want to pass an image with it.
I found a lot of examples but always without extra params.
Anyone can help?
Try the following code:
HttpClient httpClient = new HttpClient();
MultipartFormDataContent content = new MultipartFormDataContent();
content.Add(new StringContent(parameter), "name");
content.Add(new StreamContent(stream), "param", "filename");
HttpResponseMessage httpResponseMessage = await httpClient.PostAsync(address, content);

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