Local Database with Realm – Xamarin.Forms

Realm is a very popular solution for mobile databases as it includes very nice features, it’s very quick and easy to use. It supports many platforms as well as Xamarin.

You can use realm with Xamarin.Forms after installing the nuget package. Be careful to install nuget package to Android, iOS and UWP seperate project.

Current realm version is 1.5. After choosing Realm package, nuget will also install all available requirements.

First of all in order to store items in the database, you should create a model which will represent the identity that you want to save. For example lets say that we want a Person identity so we will store Persons.

Lets create the necessary model for this case:

public class Person
public string Name { get; set; }
public int Age { get; set; }

After that we  will create a test interface in which we can add some users and interact with realm.

  <StackLayout HorizontalOptions="Center" VerticalOptions="Center">
        <Entry  x:Name="name" Placeholder="Enter Name" Margin="0,20,0,0" WidthRequest="200"  />
        <Entry x:Name="age" Placeholder="Enter Age" Margin="0,20,0,0"  WidthRequest="200" />
        <Button Text="Add a new Item" Margin="0,20,0,0" Clicked="addperson" />
        <Button Text="Load all items" Margin="0,20,0,0" Clicked="loadpersons" />


To interact with the database lets create a RealHelper class which we will use to add persons and load.

public class RealmHelper
        Realm realm;
        Transaction transaction;

        public RealmHelper()
            realm = Realm.GetInstance();

        public void AddItem(Person person)

            transaction = realm.BeginWrite();
            var entry = realm.Add(person);

        public IEnumerable<Person> GetItems()
            return realm.All<Person>();


In order to make a write operation we use a transaction and we do that by creating a write with beginWrite(). More information for the functions and how they operation can be found on the documentation.



 RealmHelper rh;
public MainPage()
            rh = new RealmHelper();


The main logic comes from the two buttons:

private async void addperson(object sender, EventArgs e)
            var person = new Person();
            person.Name = name.Text;
            person.Age = age.Text;
            await DisplayAlert("Ok", "A new person was added", "OK");

        private void loadpersons(object sender, EventArgs e)
            IEnumerable<Person> collection = rh.GetItems();



Putting a breakpoint in the loadPersons button we can see the stored persons.


initialization issues I found:

  • In the UWP project you must install realm database nuget package and not realm nuget package. That’s because some functions don’t exist in the uwp apis so if you install realm package some exceptions will occur during the opening of the app.
  • Check if fody file exists in both iOS, Android and UWP projects and the its content should be
<?xml version="1.0" encoding="utf-8"?>
  • Be sure that all packages are updated across all projects and are the same version.


Extend available properties of User.Identity – Asp.Net [web api]

Asp.net web api by default contains some pre configured fields that can handle the registration of a user in a web app. Some of them are Email, Password, Confirm Password and others. You can extend those properties and include your own for your purposes with the following procedure.

First of all you need to execute some commands in the package manager. You can find nuget package manager in Tools -> Nuget Package Manager -> PM Console 

The first thing to do is to enable Migrations


The you can go to Models\AccountBindingModels.cs and add your property to the class RegisterBindingModel. Also add the same property in the Models\IdentityModels.cs inside ApplicationUser class. For example lets assume you want to add a username in the registration proccess. For this purpose you can use the following line

 public string AppUserName { get; set; }

Also include in the file.

using System;

The you must execute:

Add-Migration "AppUserName"

Those commands will run all the migration files and update the database schema to add a AppUserName column in your database.

Then update the registration action in Controllers\AccountController.cs to store AppUserName as well.

var user = new ApplicationUser() { UserName = model.Email, Email = model.Email, AppUserName = model.AppUserName };

It was that easy. you can finally find AppUserName in your database.

Display Herocard in BotFramework

As the botframework evovles, many things are changing in the apis. I wanted to create a Herocard for a bot and the previously existed method wasn’t working, so i find the new way that one can reply herocards in the user. The main function needed is the



Full C# example

 List <CardAction> list = new List<CardAction>();
            list.Add(new CardAction {Title="help", Type=ActionTypes.ImBack, Value="help" });
            list.Add(new CardAction {Title = "commands", Type = ActionTypes.ImBack, Value = "commands" });
            HeroCard hero = new HeroCard();
            hero.Title = "Hero title";
            hero.Text = "Hero text";
            hero.Buttons = list;

            var msg = context.MakeMessage();
            await context.PostAsync(msg);


The result will look like that


This github repo is very useful as it includes many botframework samples.

Query Azure Easy Tables with Postman

There is an easy way to interact with Easy Tables on Azure when you want to test things.


You can use a program like postman and create a post request for your table. For example if your table is named users, you should use users after tables/




I was testing some requests and I was dealing an exception and I figured that the request should contain the following things.

In the headers is necessary to add Content-Type and Zumo-Api-Version.



After that you should easily send your post request by selecting raw in the body section.