jQuery "POST" method

Details
Written by: Stanko Milosev
Category: Core
Hits: 2837
Here I have explained how to create empty Asp.Net Core application, now using this article here is one example on how to use jQuery Ajax call to send JSON to Asp.Net core API.

index.html: 

<!DOCTYPE html>
<head>
	<meta charset="utf-8" />
	<script defer type="text/javascript" src="lib/jquery-3.5.1.js"></script>
	<script defer type="text/javascript" src="js/index.js"></script>
</head>

<html xmlns="http://www.w3.org/1999/xhtml">
	 <button id="button" type="button">Click Me!</button> 
</html>
index.js: 
$( "#button" ).click(function() {
    var json = JSON.stringify({"cities": ["Aurel Vlaicu", "Asquins", "Arnoldstein"]});

    $.ajax({
        url: "api/Empty/",
        type: "POST",
        data: json,
        contentType: "application/json; charset=utf-8"
    }).done(function (data) {
        alert("Success.");
    }).fail(function (data) {
        alert("Sorry. Server unavailable. ");
    }); 
});
Asp.Net core API: 
using Microsoft.AspNetCore.Mvc;

namespace AspDotNetCorePostExample.Controllers
{
  [Route("api/[controller]")]
  [ApiController]
  public class EmptyController : ControllerBase
  {
    [HttpGet]
    public string Get()
    {
      return "Hello world";
    }

    [HttpPost]
    public string Get([FromBody] Filter filter)
    {
      string returnValue = string.Empty;

      foreach (var city in filter.cities)
      {
        returnValue = $"{city}, {returnValue}";
      }

      return returnValue;
    }

    public class Filter
    {
      public string[] cities { get; set; }
    }

  }
}
Notice in jQuery that in Ajax call I didn't add dataType: "json" since my API returns string and not JSON. In API notice [FromBody] in method signature, and Filter class which is defined exactly the same as JSON var json = JSON.stringify({"cities": ["Aurel Vlaicu", "Asquins", "Arnoldstein"]}); which I am sending to API.

Example download from here

Start empty Asp.Net core project

Details
Written by: Stanko Milosev
Category: Core
Hits: 2770
One my example how to start empty Asp.Net core project in Visual Studio 2019, and add one controller to it.

Start empty Asp.Net core project:

Choose ASP.NET Core Web Application:

Choose "Empty":

Since I am not using reSharper, I had to create "Controllers" folder manually. Open some file from solution and right click on tab and open containing folder:

Create new folder and name it "Controllers":

Your folder structure now should look like:

In "Controllers" folder in create new file, and Name it like EmptyController.cs, write something like 

using Microsoft.AspNetCore.Mvc;

namespace AspDotNetCorePostExample.Controllers
{
  [Route("api/[controller]")]
  [ApiController]
  public class EmptyController : ControllerBase
  {
    [HttpGet]
    public string Get()
    {
      return "Hello world";
    }
  }
}
In AspDotNetCorePostExample\AspDotNetCorePostExample\Startup.cs in method "Configure" delete: 
app.UseEndpoints(endpoints =>
{
endpoints.MapGet("/", async context =>
	  {
	await context.Response.WriteAsync("Hello World!");
  });
});
Instead write: 
app.UseEndpoints(endpoints =>
{
	endpoints.MapControllers();
});
In ConfigureServices add services.AddControllers();

Start solution and go to like "https://localhost:44336/api/Empty" (just add /api/Empty)

If you like you can manually add wwwroot folder, and use him like I already explained here. Here is new Startup.cs, and to disable HTPPS go to project properties -> Debug -> uncheck "Enable SSL":

wwwroot

Details
Written by: Stanko Milosev
Category: Core
Hits: 3175
In order to serve static files in Asp.Net Core you will need following line in Startup.cs method configure: 
app.UseStaticFiles();
When deploying in order to show default document, add following line: 
app.UseDefaultFiles();
My whole Startup.cs looks like this: 
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;

namespace AllPics2gMaps
{
  public class Startup
  {
    public Startup(IConfiguration configuration)
    {
      Configuration = configuration;
    }

    public IConfiguration Configuration { get; }

    // This method gets called by the runtime. Use this method to add services to the container.
    public void ConfigureServices(IServiceCollection services)
    {
      services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_1);
    }

    // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
    public void Configure(IApplicationBuilder app, IHostingEnvironment env)
    {
      if (env.IsDevelopment())
      {
        app.UseDeveloperExceptionPage();
      }
      else
      {
        app.UseHsts();
      }

      app.UseHttpsRedirection();
      app.UseMvc();
      app.UseDefaultFiles();
      app.UseStaticFiles();
    }
  }
}
UPDATE; Please note thatStartup.cs has been changed, refer to this article.

Enable Cross-Origin Requests (CORS) in ASP.NET Core

Details
Written by: Stanko Milosev
Category: Core
Hits: 2679
Title of this article I have took from here.

If you are receiving a message like: 

Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at http://test:2021/api/values. (Reason: CORS header ‘Access-Control-Allow-Origin’ missing)
This means that you have to enable CORS (since 2014)

In my case I have created new ASP.NET Core WebApi on the link http://test:2021/api/values, and I was accessing that link from http://gallery.milosev.com:9090.

Open Startup.cs:

First add line: 

readonly string MyAllowSpecificOrigins = "_myAllowSpecificOrigins";
Then: 
public void ConfigureServices(IServiceCollection services)
{
  services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_1);

  services.AddCors(options =>
  {
	options.AddPolicy(MyAllowSpecificOrigins,
	builder =>
	{
	  builder.WithOrigins("http://gallery.milosev.com:9090");
	});
  });
}
Here notice: http://gallery.milosev.com:9090, and at the end: 
public void Configure(IApplicationBuilder app, IHostingEnvironment env)
{
  if (env.IsDevelopment())
  {
	app.UseDeveloperExceptionPage();
  }
  else
  {
	app.UseHsts();
  }

  app.UseCors(MyAllowSpecificOrigins);
  app.UseHttpsRedirection();
  app.UseMvc();
}
Whole Startup.cs: 
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;

namespace EnableCORS
{
  public class Startup
  {
    public Startup(IConfiguration configuration)
    {
      Configuration = configuration;
    }

    public IConfiguration Configuration { get; }

    readonly string MyAllowSpecificOrigins = "_myAllowSpecificOrigins";

    // This method gets called by the runtime. Use this method to add services to the container.
    public void ConfigureServices(IServiceCollection services)
    {
      services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_1);

      services.AddCors(options =>
      {
        options.AddPolicy(MyAllowSpecificOrigins,
        builder =>
        {
          builder.WithOrigins("http://gallery.milosev.com:9090");
        });
      });
    }

    // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
    public void Configure(IApplicationBuilder app, IHostingEnvironment env)
    {
      if (env.IsDevelopment())
      {
        app.UseDeveloperExceptionPage();
      }
      else
      {
        app.UseHsts();
      }

      app.UseCors(MyAllowSpecificOrigins);
      app.UseHttpsRedirection();
      app.UseMvc();
    }
  }
}
  1. Debug Asp.Net core on IIS by attaching to process
  2. Debug Asp.Net core on IIS in VS2017
  3. Publish Asp.Net core to IIS

Subcategories

MVC 4

MVC 3

WebApi

Core

Page 11 of 12