ASP.NET Core如何使用HttpClient调用WebService
原文链接：https://www.yisu.com/jc/691937.html
我们使用VS创建一个ASP.NET Core WebAPI项目，由于是使用HttpClient，首先在ConfigureServices方法中进行注入。
public void ConfigureServices(IServiceCollection services)
{
// 注入HttpClient
services.AddHttpClient();
services.AddControllers();
}
然后添加一个名为WebServiceTest的控制器，在控制器里面添加一个Get方法，在Get方法里面取调用WebService，控制器代码如下
using Microsoft.AspNetCore.Mvc;
using System;
using System.Collections.Generic;
using System.Net;
using System.Net.Http;
using System.Threading.Tasks;
using System.Xml;
namespace HttpClientDemo.Controllers
{
[Route("api/WebServiceTest")]
[ApiController]
public class WebServiceTestController : ControllerBase
{
readonly IHttpClientFactory _httpClientFactory;
/// <summary>
/// 通过构造函数实现注入
/// </summary>
/// <param name="httpClientFactory"></param>
public WebServiceTestController(IHttpClientFactory httpClientFactory)
{
_httpClientFactory = httpClientFactory;
}
[HttpGet]
public async Task<string> Get()
{
string strResult = "";
try
{
// url地址格式：WebService地址+方法名称
// WebService地址：http://localhost:5010/WebTest.asmx
// 方法名称： PostTest
string url = "http://localhost:5010/WebTest.asmx/PostTest";
// 参数
Dictionary<string, string> dicParam = new Dictionary<string, string>();
dicParam.Add("para", "1");
// 将参数转化为HttpContent
HttpContent content = new FormUrlEncodedContent(dicParam);
strResult = await PostHelper(url, content);
}
catch (Exception ex)
{
strResult = ex.Message;
}
return strResult;
}
/// <summary>
/// 封装使用HttpClient调用WebService
/// </summary>
/// <param name="url">URL地址</param>
/// <param name="content">参数</param>
/// <returns></returns>
private async Task<string> PostHelper(string url, HttpContent content)
{
var result = string.Empty;
try
{
using (var client = _httpClientFactory.CreateClient())
using (var response = await client.PostAsync(url, content))
{
if (response.StatusCode == HttpStatusCode.OK)
{
result = await response.Content.ReadAsStringAsync();
XmlDocument doc = new XmlDocument();
doc.LoadXml(result);
result = doc.InnerText;
}
}
}
catch (Exception ex)
{
result = ex.Message;
}
return result;
}
}
}
然后启动调试，查看输出结果
调试的时候可以看到返回结果，在看看页面返回的结果。
ASP.NET Core如何使用HttpClient调用WebService
这样就完成了WebService的调用。生产环境中我们可以URL地址写在配置文件里面，然后程序里面去读取配置文件内容，这样就可以实现动态调用WebService了。我们对上面的方法进行改造，在appsettings.json文件里面配置URL地址
{
"Logging": {
"LogLevel": {
"Default": "Information",
"Microsoft": "Warning",
"Microsoft.Hosting.Lifetime": "Information"
}
},
"AllowedHosts": "*",
// url地址
"url": "http://localhost:5010/WebTest.asmx/PostTest"
}
修改控制器的Get方法
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Configuration;
using System;
using System.Collections.Generic;
using System.Net;
using System.Net.Http;
using System.Threading.Tasks;
using System.Xml;
namespace HttpClientDemo.Controllers
{
[Route("api/WebServiceTest")]
[ApiController]
public class WebServiceTestController : ControllerBase
{
readonly IHttpClientFactory _httpClientFactory;
readonly IConfiguration _configuration;
/// <summary>
/// 通过构造函数实现注入
/// </summary>
/// <param name="httpClientFactory"></param>
public WebServiceTestController(IHttpClientFactory httpClientFactory, IConfiguration configuration)
{
_httpClientFactory = httpClientFactory;
_configuration = configuration;
}
[HttpGet]
public async Task<string> Get()
{
string strResult = "";
try
{
// url地址格式：WebService地址+方法名称
// WebService地址：http://localhost:5010/WebTest.asmx
// 方法名称： PostTest
// 读取配置文件里面设置的URL地址
//string url = "http://localhost:5010/WebTest.asmx/PostTest";
string url = _configuration["url"];
// 参数
Dictionary<string, string> dicParam = new Dictionary<string, string>();
dicParam.Add("para", "1");
// 将参数转化为HttpContent
HttpContent content = new FormUrlEncodedContent(dicParam);
strResult = await PostHelper(url, content);
}
catch (Exception ex)
{
strResult = ex.Message;
}
return strResult;
}
/// <summary>
/// 封装使用HttpClient调用WebService
/// </summary>
/// <param name="url">URL地址</param>
/// <param name="content">参数</param>
/// <returns></returns>
private async Task<string> PostHelper(string url, HttpContent content)
{
var result = string.Empty;
try
{
using (var client = _httpClientFactory.CreateClient())
using (var response = await client.PostAsync(url, content))
{
if (response.StatusCode == HttpStatusCode.OK)
{
result = await response.Content.ReadAsStringAsync();
XmlDocument doc = new XmlDocument();
doc.LoadXml(result);
result = doc.InnerText;
}
}
}
catch (Exception ex)
{
result = ex.Message;
}
return result;
}
}
}
这样就可以动态调用WebService了。
