Connect to Trello Data from Blazor Apps

Blazor is a framework for developing modern, client-side web UIs using .NET technology. Instead of coding in JavaScript, developers can use the familiar C# language and .NET libraries to build app UIs.

The CData ADO.NET Provider for Trello can be used with standard ADO.NET interfaces, such as LINQ and Entity Framework, to interact with live Trello data. Since Blazor supports .NET Core, developers can use CData ADO.NET Providers in Blazor apps. In this article, we will guide you to build a simple Blazor app that talks to Trello using standard SQL queries.

Install the CData ADO.NET Provider for Trello

CData ADO.NET Providers allow users to access Trello just like they would access SQL Server, using simple SQL queries.

Install the Trello ADO.NET Data Provider from the CData website or from NuGet. Search NuGet for "Trello ADO.NET Data Provider."

Create a Trello-Connected Blazor App

Start by creating a Blazor project that references the CData ADO.NET Provider for Trello

1. Create a Blazor project on Visual Studio.
👁 Create a Blazor app project.

2. From the Solution Explorer, right click Dependencies, then click Add Project Reference.
3. In the Reference Manager, click the Browse button, and choose the .dll file of the installed ADO.NET Provider (e.g. System.Data.CData.Trello.dll, typically located at C:\Program Files\CData\CData ADO.NET Provider for Trello\lib etstandard2.0).
👁 Reference ADO.NET for Trello .dll in the Blazor app.

SELECT Trello Data from the Blazor App

1. Open the Index.razor file from the Project page.
2. In a TrelloConnection object, set the connection string:

   Trello uses token-based authentication to grant third-party applications access to their API. When a user has granted an application access to their data, the application is given a token that can be used to make requests to Trello's API.

   Trello's API can be accessed in 2 different ways. The first is using Trello's own Authorization Route, and the second is using OAuth1.0.

   • Authorization Route: At the moment of registration, Trello assigns an API key and Token to the account. See the Help documentation for information on how to connect via the Authorization route.
   • OAuth Route: Similar to using Authorization, OAuth creates an Application Id and Secret when you create your account. See the Help documentation for information on how to to connect.

   For example: APIKey=myApiKey;Token=myGeneratedToken;InitiateOAuth=GETANDREFRESH;

3. The code below creates a simple Blazor app for displaying Trello data, using standard SQL to query Trello just like SQL Server.

    @page "/"
    @using System.Data;
    @using System.Data.CData.Trello;
    
    <h1>Hello, world!</h1>
    
    Welcome to your Data app.
    
    <div class="row">
    <div class="col-12">
    
    @using (TrelloConnection connection = new TrelloConnection(
    "APIKey=myApiKey;Token=myGeneratedToken;InitiateOAuth=GETANDREFRESH;"))
    {
    var sql = "SELECT BoardId, Name FROM Boards WHERE Name = 'Public Board'";
    var results = new DataTable();
    
    TrelloDataAdapter dataAdapter = new TrelloDataAdapter(sql, connection);
    dataAdapter.Fill(results);
    
    <table class="table table-bordered">
    <thead class="thead-light">
    <tr>
    @foreach (DataColumn item in results.Rows[0].Table.Columns)
    {
    <th scope="col">@item.ColumnName</th>
    }
    </tr>
    </thead>
    <tbody>
    @foreach (DataRow row in results.Rows)
    {
    <tr>
    @foreach (var column in row.ItemArray)
    {
    <td>@column.ToString()</td>
    }
    </tr>
    }
    </tbody>
    </table>
    }
    </div>
    </div>
    

4. Rebuild and run the project. The ADO.NET Provider renders Trello data as an HTML table in the Blazor app. 👁 Query Trello from Blazor app.
   

   At this point, you have a Trello-connected Blazor app, capable of working with live Trello data just like you would work with a SQL Server instance. Download a free, 30-day trial and start working with live Trello data in your Blazor apps today.