通过HttpClient来调用Web Api接口

/// <summary>
/// HttpClient实现Post请求(异步)
/// </summary>
static async void dooPost()
{
    string url = "http://localhost:52824/api/register";
     //设置HttpClientHandler的AutomaticDecompression
    var handler = new HttpClientHandler() { AutomaticDecompression = DecompressionMethods.GZip };
    //创建HttpClient（注意传入HttpClientHandler）
    using (var http = new HttpClient(handler))
    {
        //使用FormUrlEncodedContent做HttpContent
        var content = new FormUrlEncodedContent(new Dictionary<string, string>()
        {    {"Id","6"},
             {"Name","添加zzl"},
             {"Info", "添加动作"}//键名必须为空
         });  

        //await异步等待回应  

        var response = await http.PostAsync(url, content);
        //确保HTTP成功状态值
        response.EnsureSuccessStatusCode();
        //await异步读取最后的JSON（注意此时gzip已经被自动解压缩了，因为上面的AutomaticDecompression = DecompressionMethods.GZip）
        Console.WriteLine(await response.Content.ReadAsStringAsync());
    }  

}
/// <summary>
/// HttpClient实现Get请求(异步)
/// </summary>
static async void dooGet()
{
    string url = "http://localhost:52824/api/register?id=1";
    //创建HttpClient（注意传入HttpClientHandler）
    var handler = new HttpClientHandler() { AutomaticDecompression = DecompressionMethods.GZip };  

    using (var http = new HttpClient(handler))
    {
        //await异步等待回应
        var response = await http.GetAsync(url);
        //确保HTTP成功状态值
        response.EnsureSuccessStatusCode();  

        //await异步读取最后的JSON（注意此时gzip已经被自动解压缩了，因为上面的AutomaticDecompression = DecompressionMethods.GZip）
        Console.WriteLine(await response.Content.ReadAsStringAsync());
    }
}
/// <summary>
/// HttpClient实现Put请求(异步)
/// </summary>
static async void dooPut()
{
    var userId = 1;
    string url = "http://localhost:52824/api/register?userid=" + userId;  

    //设置HttpClientHandler的AutomaticDecompression
    var handler = new HttpClientHandler() { AutomaticDecompression = DecompressionMethods.GZip };
    //创建HttpClient（注意传入HttpClientHandler）
    using (var http = new HttpClient(handler))
    {
        //使用FormUrlEncodedContent做HttpContent
        var content = new FormUrlEncodedContent(new Dictionary<string, string>()
        {
           {"Name","修改zzl"},
           {"Info", "Put修改动作"}//键名必须为空
        });  

        //await异步等待回应  

        var response = await http.PutAsync(url, content);
        //确保HTTP成功状态值
        response.EnsureSuccessStatusCode();
        //await异步读取最后的JSON（注意此时gzip已经被自动解压缩了，因为上面的AutomaticDecompression = DecompressionMethods.GZip）
        Console.WriteLine(await response.Content.ReadAsStringAsync());
    }
}  

原文地址：https://www.cnblogs.com/softwyy/p/8684792.html