Using SQLite with Xamarin Android C#

i'm a new developper in Xamarin mobile cross platform development and i have a mistake. I have a database with only one table on this time. Actually i can insert into this table but i don't know how to read in the table after. Can you help me please. This is my database class :

//SQLiteDatabase object for database handling
    private SQLiteDatabase sqldb;

    //String for Query handling
    private string sqldb_query;

    //String for Message handling
    private string sqldb_message;

    //Bool to check for database availability
    private bool sqldb_available;

    //Zero argument constructor, initializes a new instance of Database class
    public Database()
    {
        sqldb_message = "";
        sqldb_available = false;
    }

    //One argument constructor, initializes a new instance of Database class with database name parameter
    public Database(string sqldb_name)
    {
        try
        {
            sqldb_message = "";
            sqldb_available = false;
            CreateDatabase(sqldb_name);
        }
        catch (SQLiteException ex) 
        {
            sqldb_message = ex.Message;
        }
    }

    //Gets or sets value depending on database availability
    public bool DatabaseAvailable
    {
        get{ return sqldb_available; }
        set{ sqldb_available = value; }
    }

    //Gets or sets the value for message handling
    public string Message
    {
        get{ return sqldb_message; }
        set{ sqldb_message = value; }
    }

    //Creates a new database which name is given by the parameter
    public void CreateDatabase(string sqldb_name)
    {
        try
        {
            sqldb_message = "";
            string sqldb_location = System.Environment.GetFolderPath(System.Environment.SpecialFolder.Personal);
            string sqldb_path = Path.Combine(sqldb_location, sqldb_name);
            bool sqldb_exists = File.Exists(sqldb_path);
            if(!sqldb_exists)
            {
                sqldb = SQLiteDatabase.OpenOrCreateDatabase(sqldb_path,null);
                sqldb_query = "CREATE TABLE IF NOT EXISTS informations (_id INTEGER PRIMARY KEY AUTOINCREMENT, borneCode VARCHAR, magasinCode VARCHAR, subsidiary VARCHAR);";
                sqldb.ExecSQL(sqldb_query);
                sqldb_message = "Database: " + sqldb_name + " created";
            }
            else
            {
                sqldb = SQLiteDatabase.OpenDatabase(sqldb_path, null, DatabaseOpenFlags.OpenReadwrite);
                sqldb_message = "Database: " + sqldb_name + " opened";
            }
            sqldb_available=true;
        }
        catch(SQLiteException ex) 

        {
            sqldb_message = ex.Message;
        }
    }

    //Adds a new record with the given parameters
    public void AddRecord(string sborneCode, string smagasinCode, string isubsidiary)
    {
        try
        {
            sqldb_query = "INSERT INTO informations (borneCode, magasinCode, subsidiary) VALUES ('" + sborneCode + "','" + smagasinCode + "','" + isubsidiary + "');";
            sqldb.ExecSQL(sqldb_query);
            sqldb_message = "Record saved";
        }
        catch(SQLiteException ex) 
        {
            sqldb_message = ex.Message;
        }
    }

    //Updates an existing record with the given parameters depending on id parameter
    public void UpdateRecord(int iId, string sborneCode, string smagasinCode, string isubsidiary)
    {
        try
        {
            sqldb_query="UPDATE informations SET borneCode ='" + sborneCode + "', magasinCode ='" + smagasinCode + "', subsidiary ='" + isubsidiary + "' WHERE _id ='" + iId + "';";
            sqldb.ExecSQL(sqldb_query);
            sqldb_message = "Record " + iId + " updated";
        }
        catch(SQLiteException ex)
        {
            sqldb_message = ex.Message;
        }
    }

    //Deletes the record associated to id parameter
    public void DeleteRecord(int iId)
    {
        try
        {
            sqldb_query = "DELETE FROM informations WHERE _id ='" + iId + "';";
            sqldb.ExecSQL(sqldb_query);
            sqldb_message = "Record " + iId + " deleted";
        }
        catch(SQLiteException ex) 
        {
            sqldb_message = ex.Message;
        }
    }

And this is how i insert :

Database db;
    string subsidiary = "fr";
    string magasinCode = "0000";

    protected override void OnCreate (Bundle bundle)
    {
        base.OnCreate (bundle);

        db = new Database ("borne");

        // Récupère les éléments de l'UI dans resources/layout/main.axml
        SetContentView (Resource.Layout.Main);   

        // Récupère la textBox où l'on tape le code et le bouton de validation:
        EditText code = FindViewById<EditText>(Resource.Id.codeMagasin);
        Button button = FindViewById<Button>(Resource.Id.getMagasin);
        TextView nomMagasin = FindViewById<TextView> (Resource.Id.nomMagasin);

        nomMagasin.Text = db.Message;

        // Quand on clique sur valider ...
        button.Click += async (sender, e) => {

            // On récupère le code saisie et on créé la requête.
            string url = website + "?code=" + code.Text;

            // Récupère la réponse asynchronously, 
            // On parse le résultat, puis on met à jour l'écran:
            JsonValue json = await FetchWeatherAsync (url);
            if (json != null){

                db.AddRecord(code.Text, magasinCode, subsidiary);
                Console.WriteLine("Insertion OK");

                ParseAndDisplay (json);

            }
            else{
                nomMagasin.Text = "Erreur serveur";
            }
        };
    }

    // Récupère les informations du magasin en passant en paramètre l'URL du webService.
    private async Task<JsonValue> FetchWeatherAsync (string url)
    {
        // On essaye de récupérer la réponse du serveur
        try{
            // On créé une requête web HTTP avec l'url:
            HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create (new Uri (url));
            request.ContentType = "application/json";
            request.Method = "GET";

            // On envoi la requête au serveur et on attend sa réponse:
            using (WebResponse response = await request.GetResponseAsync ())
            {
                // On créé un canal de lecture pour lire la réponse du serveur:
                using (Stream stream = response.GetResponseStream ())
                {
                    // On construit le JSON document OBJECT:
                    JsonValue jsonDoc = await Task.Run (() => JsonObject.Load (stream));
                    Console.Out.WriteLine("Response: {0}", jsonDoc.ToString ());

                    // On retourne le json récupéré:
                    return jsonDoc;
                }
            }
        }
        //Si on y arrive pas, on affiche qu'on a une erreur
        catch(Exception e){
            JsonObject j = null;
            return j;
        }
    }

    // Parse le json récupéré et affiche les informations sur l'écran. 
    private void ParseAndDisplay (JsonValue json)
    {
        // On récupère la textBox où sera écrit le nom du magasin:
        TextView nomMagasin = FindViewById<TextView>(Resource.Id.nomMagasin);

        // Récupère le tableau ayant pour nom "magasin". 
        JsonValue magasin = json["title"];

        // Récupère le nom du magasin et l'écrit dans la textBox correspondant:
        nomMagasin.Text = magasin;
    }