C#：API呼び出し

前提

リクエスト仕様

POSTメソッドのJSON形式

レスポンス仕様

JSON形式で返却

API呼び出し

レスポンスのjson文字列は個々のModelに格納するのもいいけど、そのまま使うならJObjectが良いかなと思ったり…

GetResponse

public JObject GetResponse(string apiUrl, string jsonParameter)
{
    JObject response = null;
    try
    {
        HttpWebRequest request = (HttpWebRequest)WebRequest.Create(apiUrl);
        request.Method = "POST";
        request.ContentType = "application/json;";
        // カスタムヘッダーが必要の場合(認証トークンとか)
        request.Headers.Add("custom-api-param", "value");

        using (var streamWriter = new StreamWriter(request.GetRequestStream()))
        {
            streamWriter.Write(jsonParameter);
        }

        var httpResponse = (HttpWebResponse)request.GetResponse();

        // HttpStatusCodeの判断が必要なら
        if(httpResponse.StatusCode != HttpStatusCode.OK)
        {
            throw new Exception("API呼び出しに失敗しました。");
        }

        using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
        {
            response = JObject.Parse(streamReader.ReadToEnd());
        }

        // ex) response["status"]:"success"
    }
    catch (WebException wex)
    {
        // 200以外の場合
        if (wex.Response != null)
        {
            using (var errorResponse = (HttpWebResponse)wex.Response)
            {
                using (var reader = new StreamReader(errorResponse.GetResponseStream()))
                {
                    response = JObject.Parse(reader.ReadToEnd());
                }
            }
        }
    }
    
    return response;
}

API呼び出し

var apiUrl = "http://apiurl/v1/getHogepoyo"
var jsonParameter = new JavaScriptSerializer().Serialize(new
{
    name = "Name",
    email = "EmailAddress",
    password = "Password",
    detail_info = new {
            info1 = "info1",
            info2 = "info2"}
    });

JObject response = GetResponse(apiUrl, jsonParameter);