C# 调用Web Api通用方法

1.通用方法

public class GetDataByWebApi
{
    /// <summary>
    /// 通过web api获取数据的方法
    /// </summary>
    /// <param name="url">api的url</param>
    /// <param name="method">请求类型,默认是get</param>
    /// <param name="postData">post请求所携带的数据</param>
    /// <returns></returns>
    public static string RequestData(string url, string method = "Get", string postData = null)
    {
        try
        {
            method = method.ToUpper();
            //设置安全通信协议   我方公司服务器有些强制使用tls1.2的安全通信协议,所以至少包含SecurityProtocolType.Tls12   如果沒有SecurityProtocolType.Tls12设置会报错:HttpWebRequest底层连接已关闭:传送时发生意外错误
            ServicePointManager.SecurityProtocol =
                SecurityProtocolType.Ssl3 | SecurityProtocolType.Tls |
                SecurityProtocolType.Tls11 | SecurityProtocolType.Tls12;

            //创建请求实例
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);

            //设置请求类型
            request.Method = method;
            //设置请求消息主体的编码方法
            request.ContentType = "application/json";

            //POST方式處理
            if (method == "POST")
            {
                //test t = test.T;
                //t.gaga("哟西");

                //用UTF8字符集对post请求携带的数据进行编码,可防止中文乱码
                byte[] byteArray = Encoding.UTF8.GetBytes(postData);
                //指定客户端post请求携带的数据的长度
                request.ContentLength = byteArray.Length;

                //创建一个tream,用于写入post请求所携带的数据(该数据写入了请求体)
                Stream stream = request.GetRequestStream();
                stream.Write(byteArray, 0, byteArray.Length);
                stream.Close();
            }

            //获取请求的响应实例
            HttpWebResponse response = (HttpWebResponse)request.GetResponse();
            //获取读取流实体,用来以UTF8字符集读取响应流中的数据
            StreamReader myStreamReader = new StreamReader(response.GetResponseStream(), /*Encoding.UTF8*/Encoding.Default);
            //进行数据读取
            string retString = myStreamReader.ReadToEnd();
            myStreamReader.Close();
            return retString;
        }
        catch (Exception ex)
        {
            //拋出異常
            //throw ex;
            return ex.Message;
        }
    }
}

注：需要引用Newtonsoft.Json.dll下的Newtonsoft.Json;

2.模拟发送自定义类数据

（1）自定义类

/// <summary>
/// 请求参数
/// </summary>
public class ASK
{
    /// <summary>
    /// 自定义数据体
    /// </summary>
    public Dictionary<object, object> data { get; set; }
    /// <summary>
    /// 功能名
    /// </summary>
    public string fun { get; set; }
    /// <summary>
    /// 消息id,服务端接收后会原样返回，websocket连接可用用来异步转同步用。http模式直接填0
    /// </summary>
    public string msgid { get; set; }

    public ASK(Dictionary<object, object> data, string fun, string msgid)
    {
        this.data = data;
        this.fun = fun;
        this.msgid = msgid;
    }

    public ASK()
    {

    }
}

（2）模拟发送

/// <summary>
/// http请求方式调用web api
/// </summary>
/// <param name="ask">请求参数</param>
/// <returns>返回调用结果</returns>
public string HttpApi(ASK ask)
{
    if (ask != null)
    {
        string jsonstr = JsonConvert.SerializeObject(ask);
        string result = GetDataByWebApi.RequestData("http://127.0.0.1:9912/api", "POST", jsonstr);
        return result;
    }
    else { return ""; }
}

public void PostSend()
{
    ASK D = new ASK() { data = new Dictionary<object, object>(), fun = "get_device_list", msgid = "0" };
    string jsonstr = JsonConvert.SerializeObject(D);
    string result = GetDataByWebApi.RequestData("http://127.0.0.1:9912/api", "POST", jsonstr);//post方式发送
　　//string result = GetDataByWebApi.RequestData("http://127.0.0.1:9912/api?fun=get_device_list");//Get方式发送
    MessageBox.Show(result);
}