Create ASP.NET Core 3 Web API Project
On the Visual Studio, create new ASP.NET Core Web Application project
Input Project Name and select Project Location
Select Empty Template and click Create button to Finish
Structure of New Project
Add Configurations
Open Startup.cs file and add new configurations as below:
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
namespace LearnASPNETCore3WebAPIWithRealApps
{
public class Startup
{
public void ConfigureServices(IServiceCollection services)
{
services.AddControllers();
}
public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
}
app.UseRouting();
app.UseEndpoints(endpoints =>
{
endpoints.MapControllers();
});
}
}
}
Create Controller
Create new folder named Controllers. In this folder, create new controller named DemoController.cs as below:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Mvc;
namespace LearnASPNETCore3WebAPIWithRealApps.Controllers
{
[Route("api/demo")]
public class DemoController : Controller
{
[Produces("text/plain")]
[HttpGet("demo1")]
public async Task<IActionResult> Demo1()
{
try
{
string result = "Hello World";
return Ok(result);
}
catch
{
return BadRequest();
}
}
}
}
Structure of ASP.NET Core 3 Web API Project
Testing Web API
Access Web API use the following url: http://localhost:18942/api/demo/demo1
Output
Hello World
Consume Web API from Console Application
Create Console App (.NET Framework) Project in Visual Studio.
Create DemoRestClientModel
DemoRestClientModel class contain methods call Web API
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Text;
using System.Threading.Tasks;
namespace LearnASPNETCore3WebAPIWithRealApps_Client
{
public class DemoRestClientModel
{
private string BASE_URL = "http://localhost:18942/api/demo/";
public Task<HttpResponseMessage> Demo1()
{
try
{
HttpClient client = new HttpClient();
client.BaseAddress = new Uri(BASE_URL);
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("text/plain"));
return client.GetAsync("demo1");
}
catch
{
return null;
}
}
}
}
Run Console Application
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Text;
using System.Threading.Tasks;
namespace LearnASPNETCore3WebAPIWithRealApps_Client
{
class Program
{
static void Main(string[] args)
{
DemoRestClientModel demoRestClientModel = new DemoRestClientModel();
HttpResponseMessage httpResponseMessage = demoRestClientModel.Demo1().Result;
HttpStatusCode httpStatusCode = httpResponseMessage.StatusCode;
Console.WriteLine("Status Code: " + httpStatusCode);
bool isSuccessStatusCode = httpResponseMessage.IsSuccessStatusCode;
Console.WriteLine("IsSuccessStatusCode: " + isSuccessStatusCode);
string result = httpResponseMessage.Content.ReadAsStringAsync().Result;
Console.WriteLine("Result: " + result);
Console.ReadLine();
}
}
}
Output
Status Code: OK
IsSuccessStatusCode: True
Result: Hello World