C#发送POST,GET,DELETE请求API，并接受返回值

发送POST请求

/// <summary>
/// API发送POST请求
/// </summary>
/// <param name="url">请求的API地址</param>
/// <param name="parametersJson">POST过去的参数（JSON格式）字符串</param>
/// <returns></returns>
public static string ApiPost(string url, string parametersJson)
{
    HttpClient client = new HttpClient();
    client.BaseAddress = new Uri(System.Configuration.ConfigurationManager.AppSettings["ApiHttp"]);
    // 为JSON格式添加一个Accept报头
    client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
    //需要传递的参数（参数封装成JSON）
    HttpContent content = new StringContent(parametersJson)
    {
        Headers = { ContentType = new MediaTypeHeaderValue("application/json") }
    };
 
    HttpResponseMessage response = client.PostAsync(url, content).Result;
    response.EnsureSuccessStatusCode();
    return response.Content.ReadAsStringAsync().Result;
} 

发送GET请求

/// <summary>
/// API发送GET请求，返回Json
/// </summary>
/// <param name="url"></param>
/// <returns>如果未成功返回空</returns>
public static string ApiGet(string url)
{
    HttpClient client = new HttpClient();
    client.BaseAddress = new Uri(System.Configuration.ConfigurationManager.AppSettings["ApiHttp"]);
    // 为JSON格式添加一个Accept报头
    client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
    HttpResponseMessage response = client.GetAsync(url).Result;
    if (response.IsSuccessStatusCode)
    {
        return response.Content.ReadAsStringAsync().Result;
    }
    return "";
} 

发送DELETE请求

/// <summary>
///  API发送DELETE请求，返回状态：200成功，201失败
/// </summary>
/// <param name="url"></param>
/// <returns></returns>
public static string ApiDelete(string url)
{
    HttpClient client = new HttpClient();
    client.BaseAddress = new Uri(System.Configuration.ConfigurationManager.AppSettings["ApiHttp"]);
    // 为JSON格式添加一个Accept报头
    client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
    HttpResponseMessage response = client.DeleteAsync(url).Result;
    if (response.IsSuccessStatusCode)
    {
        return response.Content.ReadAsStringAsync().Result;
    }
    return "";
}