ASP.NET Core使用HttpClient的同步和异步请求

using System;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.IO;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Text;
using System.Threading.Tasks;
using System.Web;

namespace Common
{
public class HttpHelper
{/// <summary>
/// 发起POST同步请求
///
/// </summary>
/// <param name="url"></param>
/// <param name="postData"></param>
/// <param name="contentType">application/xml、application/json、application/text、application/x-www-form-urlencoded</param>
/// <param name="headers">填充消息头</param>
/// <returns></returns>
public static string HttpPost(string url, string postData = null, string contentType = null, int timeOut = 30, Dictionary<string, string> headers = null)
{
postData = postData ?? "";
using (HttpClient client = new HttpClient())
{
if (headers != null)
{
foreach (var header in headers)
client.DefaultRequestHeaders.Add(header.Key, header.Value);
}
using (HttpContent httpContent = new StringContent(postData, Encoding.UTF8))
{
if (contentType != null)
httpContent.Headers.ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue(contentType);

HttpResponseMessage response = client.PostAsync(url, httpContent).Result;
return response.Content.ReadAsStringAsync().Result;
}
}
}

/// <summary>
/// 发起POST异步请求
/// </summary>
/// <param name="url"></param>
/// <param name="postData"></param>
/// <param name="contentType">application/xml、application/json、application/text、application/x-www-form-urlencoded</param>
/// <param name="headers">填充消息头</param>
/// <returns></returns>
public static async Task<string> HttpPostAsync(string url, string postData = null, string contentType = null, int timeOut = 30, Dictionary<string, string> headers = null)
{
postData = postData ?? "";
using (HttpClient client = new HttpClient())
{
client.Timeout = new TimeSpan(0, 0, timeOut);
if (headers != null)
{
foreach (var header in headers)
client.DefaultRequestHeaders.Add(header.Key, header.Value);
}
using (HttpContent httpContent = new StringContent(postData, Encoding.UTF8))
{
if (contentType != null)
httpContent.Headers.ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue(contentType);

HttpResponseMessage response = await client.PostAsync(url, httpContent);
return await response.Content.ReadAsStringAsync();
}
}
}

/// <summary>
/// 发起GET同步请求
/// </summary>
/// <param name="url"></param>
/// <param name="headers"></param>
/// <param name="contentType"></param>
/// <returns></returns>
public static string HttpGet(string url, string contentType = null, Dictionary<string, string> headers = null)
{
using (HttpClient client = new HttpClient())
{
if (contentType != null)
client.DefaultRequestHeaders.Add("ContentType", contentType);
if (headers != null)
{
foreach (var header in headers)
client.DefaultRequestHeaders.Add(header.Key, header.Value);
}
HttpResponseMessage response = client.GetAsync(url).Result;
return response.Content.ReadAsStringAsync().Result;
}
}

/// <summary>
/// 发起GET异步请求
/// </summary>
/// <param name="url"></param>
/// <param name="headers"></param>
/// <param name="contentType"></param>
/// <returns></returns>
public static async Task<string> HttpGetAsync(string url, string contentType = null, Dictionary<string, string> headers = null)
{
using (HttpClient client = new HttpClient())
{
if (contentType != null)
client.DefaultRequestHeaders.Add("ContentType", contentType);
if (headers != null)
{
foreach (var header in headers)
client.DefaultRequestHeaders.Add(header.Key, header.Value);
}
HttpResponseMessage response = await client.GetAsync(url);
return await response.Content.ReadAsStringAsync();
}
}
}
}

调用异步请求方法：

var result = await HttpHelper.HttpPostAsync("http://www.baidu.com/api/getuserinfo", "userid=23456798");