Connect to Gmail 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 Gmail can be used with standard ADO.NET interfaces, such as LINQ and Entity Framework, to interact with live Gmail 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 Gmail using standard SQL queries.

Install the CData ADO.NET Provider for Gmail

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

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

Create a Gmail-Connected Blazor App

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

1. Create a Blazor project on Visual Studio.
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.Gmail.dll, typically located at C:\Program Files\CData\CData ADO.NET Provider for Gmail\lib etstandard2.0).

SELECT Gmail Data from the Blazor App

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

   There are two ways to authenticate to Gmail. Before selecting one, first ensure that you have enabled IMAP access in your Gmail account settings. See the "Connecting to Gmail" section under "Getting Started" in the installed documentation for a guide.

   The User and Password properties, under the Authentication section, can be set to valid Gmail user credentials.

   Alternatively, instead of providing the Password, you can use the OAuth authentication standard. To access Google APIs on behalf on individual users, you can use the embedded credentials or you can register your own OAuth app.

   OAuth also enables you to use a service account to connect on behalf of users in a Google Apps domain. To authenticate with a service account, you will need to register an application to obtain the OAuth JWT values.

   In addition to the OAuth values, you will need to provide the User. See the "Getting Started" chapter in the help documentation for a guide to using OAuth.

   For example: User=username;Password=password;

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

         @page "/"
         @using System.Data;
         @using System.Data.CData.Gmail;
         
         <h1>Hello, world!</h1>
         
         Welcome to your Data app.
         
         <div class="row">
             <div class="col-12">
         
                 @using (GmailConnection connection = new GmailConnection(
                   "User=username;Password=password;"))
                 {
                     var sql = "SELECT Subject, Size FROM Inbox";
                     var results = new DataTable();
         
                     GmailDataAdapter dataAdapter = new GmailDataAdapter(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 Gmail data as an HTML table in the Blazor app.

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