WinForm 对Web Api 增 册 改 查 的基本操作

WebApi代码：

 public class ValuesController : ApiController
    {
     
          Entities db=new Entities();
   
        // GET api/values
        public IEnumerable<Person> Get()
        {
            return  db.Person;
        }

        // GET api/values/5
        public Person Get(int id)
        {
            return db.Person.FirstOrDefault(o => o.id == id);
        }

        // POST api/values
        public void Post([FromBody]Person value)
        {
            // People peple =(People) JsonConvert.DeserializeObject(value);
            if (db.Person.FirstOrDefault(o => o.id == value.id) == null)
            {
                db.Person.Add(value); 
            }
            db.SaveChanges();
        }

        // PUT api/values/5
        public void Put(int id, [FromBody]Person value)
        {
            var query = db.Person.FirstOrDefault(o => o.id == id);
            if (query != null)
            {
                query.Name = value.Name;
            }
            db.SaveChanges();
        }

        // DELETE api/values/5
        public void Delete(int id)
        {
            var query = db.Person.FirstOrDefault(o => o.id == id);
            if (query != null)
            {
                db.Person.Remove(query);
                db.SaveChanges();
            }
          
           
        }
    }

Winform的基本代码：

 private Uri url = new Uri("http://localhost:18827/api/values");

 /// <summary>
        /// 增
        /// </summary>
        private async void button1_Click(object sender, EventArgs e)
        {
            People people = new People();
            people.Id = new Random().Next(100, 9999999);
            people.Name = "李" + people.Id;
            string data = JsonConvert.SerializeObject(people);

            //创建一个处理序列化的DataContractJsonSerializer
            DataContractJsonSerializer serializer = new DataContractJsonSerializer(typeof(People));
            MemoryStream ms = new MemoryStream();
            serializer.WriteObject(ms, people);
            //一定要在这设定Position
            ms.Position = 0;
            HttpContent content = new StreamContent(ms);//将MemoryStream转成HttpContent
            //一定要设定Header
            content.Headers.ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue("application/json");
            HttpClient client = new HttpClient();
            //由HttpClient发出Post Method
            HttpResponseMessage response = await client.PostAsync(url, content);

            if (response.IsSuccessStatusCode)
            {

            }
            else
            {

            }



        }

        /// <summary>
        /// 删除
        /// </summary>
        private async void button2_Click(object sender, EventArgs e)
        {
                HttpClient client = new HttpClient();
                //由HttpClient发出Delete Method
                HttpResponseMessage response = await client.DeleteAsync(url +"/1");
                if (response.IsSuccessStatusCode)
                {
                    MessageBox.Show("成功");
                }
        }

        //修改
        private async void button3_Click(object sender, EventArgs e)
        {
            //创建一个处理序列化的DataContractJsonSerializer
            DataContractJsonSerializer serializer = new DataContractJsonSerializer(typeof(People));
            MemoryStream ms = new MemoryStream();
            //将资料写入MemoryStream
            serializer.WriteObject(ms, new People() { Id = 1, Name = "Hello ni" });
            //一定要在这设定Position
            ms.Position = 0;
            HttpContent content = new StreamContent(ms);//将MemoryStream转成HttpContent
            content.Headers.ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue("application/json");
            HttpClient client = new HttpClient();
           //由HttpClient发出Put Method
            HttpResponseMessage response = await client.PutAsync(url + "/1", content);
            if (response.IsSuccessStatusCode)
            {
                MessageBox.Show("成功");
            }
        }

        /// <summary>
        /// 获取所有
        /// </summary>
        private void button4_Click(object sender, EventArgs e)
        {
            using (WebClient client = new WebClient())
            {
                client.Headers["Type"] = "GET";
                client.Headers["Accept"] = "application/json";
                client.Encoding = Encoding.UTF8;
                client.DownloadStringCompleted += (senderobj, es) =>
                {
                    if (es.Result != null)
                    {
                        var test = JsonConvert.DeserializeObject<People[]>(es.Result);
                        dataGridView1.DataSource = test;
                    }
                };
                client.DownloadStringAsync(url);


            }
        }