C# Change content-disposition with webclient

Question

I would like to upload a file on a specific website with C# and the WebClient class. I have this code :

 Console.Write("\nPlease enter the URI to post data to : ");

            String uriString = "http://www.noelshack.com/api.php";
          //  String uriString = "http://127.0.0.1/upload.php";


            WebClient myWebClient = new WebClient();
            string fileName = lst_path[0];
            byte[] responseArray = myWebClient.UploadFile(uriString,"POST", fileName);

            MessageBox.Show("\nretour:" + System.Text.Encoding.ASCII.GetString(responseArray));

But the problem, on the website the name of the file input is "fichier" and webclient send "file" as name .

I would like it to send :

Content-Disposition: form-data; name="fichier"; filename="csharp.jpg" instead of : Content-Disposition: form-data; name="file"; filename="csharp.jpg"

I didn't find how to modify this filed, some help please ?

Answer 1

If you have .NET 4.5+, you can use the HttpClient class to do an asynchronous post:

async Task<string> UploadFileAsync(string[] lst_path)
{
    string uriString = "http://www.noelshack.com/api.php";
    string fileName = lst_path[0];
    using (HttpClient client = new HttpClient())
    using (FileStream fs = new FileStream(fileName, FileMode.Open, FileAccess.Read))
    using (MultipartFormDataContent form = new MultipartFormDataContent())
    using (StreamContent sc = new StreamContent(fs))
    {
        form.Add(sc, "fichier", fileName);
        HttpResponseMessage response = await client.PostAsync(uriString, form);
        response.EnsureSuccessStatusCode();
        return await response.Content.ReadAsStringAsync();
    }
}