Announcing Microsoft ASP.NET WebHooks V1

WebHooks provide a simple pub/sub model for wiring together Web APIs and services with your code. A WebHook can be used to get notified when a file has changed in Dropbox, a code change has been committed to GitHub, a payment has been initiated in PayPal, a card has been created in Trello, and much more — the possibilities are endless! When subscribing, you provide a callback URI where you want to be notified. When an event occurs, an HTTP POST request is sent to your callback URI with information about what happened so that your Web app can act accordingly. WebHooks happen without polling and with no need to hold open a network connection while waiting for notifications.

Receiving WebHooks

Dealing with WebHooks depends on who the sender is. Sometimes there are additional steps registering a WebHook verifying that the subscriber is really listening. Often the security model varies quite a bit. Some WebHooks provide a push-to-pull model where the HTTP POST request only contains a reference to the event information which is then to be retrieved independently.

The purpose of Microsoft ASP.NET WebHooks is to make it both simpler and more consistent to wire up your API without spending a lot of time figuring out how to handle any WebHook variant:


A WebHook handler is where you process the incoming WebHook. Here is a sample handler illustrating the basic model. No registration is necessary – it will automatically get picked up and called:

public class MyHandler : WebHookHandler
    // The ExecuteAsync method is where to process the WebHook data regardless of receiver
    public override Task ExecuteAsync(string receiver, WebHookHandlerContext context)
        // Get the event type          
        string action = context.Actions.First();
        // Extract the WebHook data as JSON or any other type as you wish
        JObject data = context.GetDataOrDefault();
        return Task.FromResult(true);

Finally, we want to ensure that we only receive HTTP requests from the intended party. Most WebHook providers use a shared secret which is created as part of subscribing for events. The receiver uses this shared secret to validate that the request comes from the intended party. It can be provided by setting an application setting in the Web.config file, or better yet, configured through the Azure portal or even retrieved from Azure Key Vault.

For more information about receiving WebHooks and lots of samples, please see these resources:

More detail on Microsoft Blog.

How do I extract text that lies between two strings?

My initial prolem was to extract from a SQL string generated by MySql, all fields. I had a string like

INSERT INTO `inventoryapp`.`inventory_keys`
(<{Id: }>,
<{PropertyId: }>,
<{AppointmentId: }>,
<{SectionType: }>,
<{KeysDescription: }>,
<{FobsWorking: }>,
<{EntryCodes: }>,
<{AlarmCodes: }>,
<{Notes: }>,
<{Version: }>,
<{CreatedDate: }>,
<{CreatedBy: }>,
<{UpdatedDate: }>,
<{UpdatedBy: }>,
<{IsDeleted: }>);

With a bit of RegEx I can extract all fields with the following function:

public IEnumerable<string> GetSubStrings(string input, string start, 
                                         string end) {
    Regex r = new Regex(Regex.Escape(start) + "(.*?)" + Regex.Escape(end));
    MatchCollection matches = r.Matches(input);
    foreach (Match match in matches)
        yield return match.Groups[1].Value;

Then if you want to have in a single line this query and generate the list of fields to have a list of parameters for a MySqlCommand for example, you can use the following function:

string strSQL = yoursql.Replace(Environment.NewLine, "")
                       .Replace("\r", " ");
string strParameters = "";

List<string> prm = GetSubStrings(strSQL, "<{", ": }>").ToList();
foreach(string s in prm) {
    string tmp = s.Replace("?", "");
    strParameters += Environment.NewLine + 
        $"cmd.Parameters.Add(\"?{tmp}\", MySqlDbType.VarChar)" +
        $".Value = record.{tmp}"; ;
this.textBoxParams.Text = strParameters;

strSQL = strSQL.Replace("`inventoryapp`.", "");
strSQL = strSQL.Replace("<{", "?").Replace(": }>", "");

Happy coding!

It’s a Good Day to Be a C# Developer


Recently at Connect(), Microsoft made a slew of new announcements. First, the public availability of Visual Studio 2017 Release Candidate. This just isn't a new version of the signature developer tool, it also includes the latest bits for C# 7.0. Second, Google announced they were joining the .NET Foundation. This means that Google, technically a competitor of Microsoft, wants to be actively involved in the evolution of .NET (and indirectly C#). Third, the first public release of Visual Studio for Mac. As a native environment, Visual Studio for Mac will provide the same world class tooling support for Xamarin applications, using C# and F#.

We could go on, but there is a common thread that runs between many of these announcements. As a developer, choosing C# as a part of your technology stack is an excellent decision! But what if you are not a C# developer already? How does C# compare to other popular languages such as JavaScript, Java, Python, etc?

Migrate SQLite to MySQL

I’m developing a huge app made with Xamarin Forms in my company. A problem was to create all tables in the device with SQLite to the main database MySql.


I found a way to create all tables quickly with a tool called SQLite to MySQL.

SQLite-to-MySQL is a powerful and reliable tool to convert SQLite databases to MySQL, MariaDB or Percona format. The program has high performance due to direct connection to source and destination databases (it does not use ODBC or any other middleware software). Command line support allows to script, automate and schedule the conversion process.




  • All versions of Linux/Unix and Windows MySQL servers are supported
  • Option to customize resulting table structure
  • Convert indexes and relationships between tables
  • Stores conversion settings into profile
  • Option to filter data using SELECT-queries
  • Option to merge SQLite data into an existing MySQL database
  • Option to synchronize MySQL database with SQLite data
  • Support for multibyte character sets
  • Option to export SQLite database into MySQL script file
  • Verified compatibility with MariaDB and Percona
  • Option to customize MySQL storage engine and MySQL charset
  • Special approach for Virtual Server users
  • Command line support
  • Easy-to-use wizard-style interface
  • Full install/uninstall support
  • Unlimited 24/7 support service
  • 1-year subscription for updates

Click here to download and try it.

Xamarin Forms and Google Mobile Ads for iOS: update

In my previous post I explaind how to add on your application advertising. In those days Xamarin has removed from the Component Store the component called Google Mobile Ads for iOS.

Now you have to install another component called Firebase AdMob for iOS.


After installed this component you can see in your Output window a similar info without see an advert in your app:

2016-11-18 11:28:14.853 WordBankEasy.iOS[11103:2250070] <Google> You must set the rootViewController property of <GADBannerView: 0x1034702c0; frame = (-10 0; 320 50); clipsToBounds = YES; layer = <CALayer: 0x174e39d40>> before loading a request.

To fix this issue you have to find before the right UIViewController. For that you can use the following code:

    UIViewController viewController = null;
    foreach (UIWindow rootView in UIApplication.SharedApplication.Windows) {
        if (rootView != null) {
            viewController = rootView.RootViewController;

    adView = new BannerView(size: AdSizeCons.Banner,
                            origin: new CGPoint(-10, 0))
        AdUnitID = AdmobID,
        RootViewController = viewController

Happy coding!

Xamarin Forms Components

Hello guys!

From today on Nuget there are 4 new components for Xamarin Forms created by me.

Happy coding!

Convert Hex Color Code to Brush/SolidColorBrush in XAML App

To set the background color of an object in .NET XAML, you will need to set the Brush object type. To create a Brush object from a hexadecimal color code, use the following.

//input ex: #dcdcdc
public static Windows.UI.Xaml.Media.SolidColorBrush 
        GetColorFromHex(string hexaColor)
	return new Windows.UI.Xaml.Media.SolidColorBrush(
			Convert.ToByte(hexaColor.Substring(1, 2), 16),
			Convert.ToByte(hexaColor.Substring(3, 2), 16),
			Convert.ToByte(hexaColor.Substring(5, 2), 16)

Happy coding!

$.ajax No 'Access-Control-Allow-Origin' header is present on the requested resource with WebAPI

I want to get data from a WebAPI with jquery

        $("#btnSend").click(function () {
                type: 'GET',
                url: '/Report/SendEmail?quote=18',
                crossDomain: true,
                success: function (msg) {
                    if (msg == 'True') {
                        alert('Email sent to the client');
                error: function (request, status, error) {

and it produce

‘No Access-Control-Allow-Origin' header is present on the requested resource error.

The solution is to add in the result of the WebAPI the following code:

            Response.Headers.Add("Access-Control-Allow-Methods", "GET, POST");
            Response.Headers.Add("Access-Control-Allow-Headers", "accept, authority");
            Response.Headers.Add("Access-Control-Allow-Credentials", "true");

Happy coding!

How Do I Add a Splitter to my WPF Window?

Splitters are a useful UI feature where the width or height of a control on the form can be modified to show more or less information.

An Example of this is the splitter between the folder tree-view in and the file and subfolder detail view in Windows Explorer, allowing the size of the folder tree-view on the left-hand side of the form to be sized up to 50% of the form width. Windows Forms 1.1 included a Splitter control, and Windows Forms 2.0 included a SplitContainer.

WPF does not have equivalent versions of either of these controls; however it is possible to add splitters to your WPF application using the WPF Grid, and a GridSplitter. The example code below allows the two columns in the grid to be re-sized. This is done by adding a GridSplitter as a child item of the Grid.

<Window x:Class="PSC.Splitter.Window1"
    Title="PSC.Splitter" Height="300" Width="300">
        <ColumnDefinition />
        <ColumnDefinition />
      <StackPanel Background="#feca00" Grid.Column="0">
        <TextBlock FontSize="35" Foreground="#58290A" 
                   TextWrapping="Wrap">Left Hand Side</TextBlock>
      <Border CornerRadius="10" BorderBrush="#58290A" 
              BorderThickness="5" Grid.Column="1">
        <TextBlock FontSize="25" Margin="20" Foreground="#FECA00" 
                   TextWrapping="Wrap">Right Hand Side</TextBlock>

Happy coding!

Custom editor render for Xamarin on iOS

In Xamairin the Editor component doesn’t have a border on iOS. If you want to add one in the iOS project just added the following code.

using UIKit;
using WordBankEasy.iOS.Renderers;
using Xamarin.Forms;
using Xamarin.Forms.Platform.iOS;

[assembly: ExportRenderer(typeof(Editor), typeof(CustomEditorRenderer))]
namespace PSC.iOS.Renderers
    public class CustomEditorRenderer : EditorRenderer
        protected override void OnElementChanged(
			    ElementChangedEventArgs<Editor> e)

            if(Control != null)
                Control.Layer.BorderColor = 
                              UIColor.FromRGB(204, 204, 204).CGColor;
                Control.Layer.BorderWidth = 0.5f;
                Control.Layer.CornerRadius = 3f;

Happy coding!