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();
});
}
}
}
Entities Class
Create Models folder. In this folder, create new class named Product.cs as below:
Product Entity
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
namespace LearnASPNETCore3WebAPIWithRealApps.Models
{
public class Product
{
public string Id { get; set; }
public string Name { get; set; }
public double Price { get; set; }
}
}
Create Controller
Create new folder named Controllers. In this folder, create new controller named ProductController.cs as below:
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using LearnASPNETCore3WebAPIWithRealApps.Models;
namespace LearnASPNETCore3WebAPIWithRealApps.Controllers
{
[Route("api/product")]
public class ProductController : Controller
{
[Produces("application/json")]
[HttpGet("find")]
public async Task<IActionResult> Find()
{
try
{
var product = new Product() { Id = "p01", Name = "name 1", Price = 2 };
return Ok(product);
}
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/product/find
Output
{"id":"p01","name":"name 1","price":2.0}
Consume Web API from Console Application
Create Console App (.NET Framework) Project in Visual Studio.
Entity Class
Create Models folder in Console Application. In this folder, create new class named Product.cs as below:
Product Entity
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace LearnASPNETCore3WebAPIWithRealApps_Client.Models
{
public class Product
{
public string Id { get; set; }
public string Name { get; set; }
public double Price { get; set; }
}
}
Create ProductRestClientModel
ProductRestClientModel class contain methods call Web API. Add reference to Microsoft.AspNet.WebApi.Client library from Nuget Packages
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 ProductRestClientModel
{
private string BASE_URL = "http://localhost:18942/api/product/";
public Task<HttpResponseMessage> Find()
{
try
{
HttpClient client = new HttpClient();
client.BaseAddress = new Uri(BASE_URL);
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
return client.GetAsync("find");
}
catch
{
return null;
}
}
}
}
Run Console Application
using LearnASPNETCore3WebAPIWithRealApps_Client.Models;
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)
{
ProductRestClientModel productRestClientModel = new ProductRestClientModel();
HttpResponseMessage httpResponseMessage = productRestClientModel.Find().Result;
HttpStatusCode httpStatusCode = httpResponseMessage.StatusCode;
Console.WriteLine("Status Code: " + httpStatusCode);
bool isSuccessStatusCode = httpResponseMessage.IsSuccessStatusCode;
Console.WriteLine("IsSuccessStatusCode: " + isSuccessStatusCode);
Product product = httpResponseMessage.Content.ReadAsAsync<Product>().Result;
Console.WriteLine("Product Info");
Console.WriteLine("Id: " + product.Id);
Console.WriteLine("Name: " + product.Name);
Console.WriteLine("Price: " + product.Price);
Console.ReadLine();
}
}
}
Output
Status Code: OK
IsSuccessStatusCode: True
Product Info
Id: p01
Name: name 1
Price: 12.0