Build a Simple VCL Application for Stack Exchange Data

Embarcadero RAD Studio provides a development environment for Delphi and C++Builder applications. With the CData ODBC Driver for Stack Exchange, you gain access to live Stack Exchange data within RAD Studio, abstracting the data into tables, views, and stored procedures that can be used to retrieve Stack Exchange data. This article will walk through connecting to Stack Exchange and creating a simple VCL application with the Form Designer.

Create a Connection to Stack Exchange Data

If you have not already, first specify connection properties in an ODBC DSN (data source name). This is the last step of the driver installation. You can use the Microsoft ODBC Data Source Administrator to create and configure ODBC DSNs.

Start by setting the Profile connection property to the location of the Stack Exchange Profile on disk (e.g. C:\profiles\StackExchange.apip). Next, set the ProfileSettings connection property to the connection string for Stack Exchange (see below).

Stack Exchange API Profile Settings

Register an application on StackApps to obtain an API Key. The Site property specifies which Stack Exchange site to query (e.g., stackoverflow).

You can then follow the steps below to use the Data Explorer to create a FireDAC connection to Stack Exchange data.

1. In a new VCL Forms application, expand the FireDAC node in the Data Explorer.
2. Right-click the ODBC Data Source node in the Data Explorer.
3. Click Add New Connection.
4. Enter a name for the connection.
5. In the FireDAC Connection Editor that appears, set the DataSource property to the name of the ODBC DSN for Stack Exchange.

Create VCL Applications with Connectivity to Stack Exchange Data

Follow the procedure below to start executing queries to Stack Exchange data from a simple VCL application that displays the results of a query in a grid.

1. Drop a TFDConnection component onto the form and set the following properties:

   • ConnectionDefName: Select the FireDAC connection to Stack Exchange data.
   • Connected: Select True from the menu and, in the dialog that appears, enter your credentials.

2. Drop a TFDQuery component onto the form and set the properties below:

   • Connection: Set this property to the TFDConnection component, if this component is not already specified.

   • SQL: Click the button in the SQL property and enter a query. For example:

     SELECT AnswerId, CreationDate FROM Answers WHERE IsAccepted = 'true'
     

   • Active: Set this property to true.

3. Drop a TDataSource component onto the form and set the following property:

   • DataSet: In the menu for this property, select the name of the TFDQuery component.

4. Drop a TDBGrid control onto the form and set the following property:

   • DataSource: Select the name of the TDataSource.
5. Drop a TFDGUIxWaitCursor onto the form — this is required to avoid a run-time error.

You now have an executable application that displays the results of the SQL Query set in the TFDQuery object.

Related Articles

Below you can find other articles for using the CData ODBC Driver with RAD Studio, Delphi, and C++ Builder.

• DataBind Controls to Stack Exchange Data in C++Builder
• DataBind Controls to Stack Exchange Data in Delphi
• Viewing Stack Exchange Data in RAD Studio Data Explorer