如何在调用 C# 时在 web API 中添加参数

Question

I have given below the sample code, I am calling web API but I am struggling to pass the parameter in the console application.

C# code:

HttpClient client = new HttpClient();
var responseTask = client.GetAsync("<web api name>");
responseTask.Wait();

HttpRequestMessage rm = new HttpRequestMessage();
var headers = rm.Headers;

client.DefaultRequestHeaders.Add("client_id", "1234xv");
client.DefaultRequestHeaders.Add("client_secret", "7dfdfsd");

if (responseTask.IsCompleted)
{
    var result = responseTask.Result;

    if (result.IsSuccessStatusCode)
    {
        var messageTask = result.Content.ReadAsStringAsync();
        messageTask.Wait();                    
        Console.WriteLine("Message from Web API:" + messageTask.Result);                  
        Console.ReadLine();
    }
}

Answer 1

You were making the GET call much early, even before adding the parameters to the HTTP headers. You need to add the params and then call the GetAsync(). See the modified code below,

using (HttpClient client = new HttpClient())
{
   client.DefaultRequestHeaders.Add("client_id", "1234xv");
   client.DefaultRequestHeaders.Add("client_secret", "7dfdfsd");

   var responseTask = client.GetAsync("http://your api url");
   responseTask.Wait();
   if (responseTask.IsCompleted)
   {
      var result = responseTask.Result;
      if (result.IsSuccessStatusCode)
      {
          var messageTask = result.Content.ReadAsStringAsync();
          messageTask.Wait();
          Console.WriteLine("Message from Web API:" + messageTask.Result);
          Console.ReadLine();
      }
   }
}