Build a Simple VCL Application for LDAP Objects

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

Create a Connection to LDAP Objects

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.

To establish a connection, the following properties under the Authentication section must be provided:

• Valid User and Password credentials (e.g., Domain\BobF or cn=Bob F,ou=Employees,dc=Domain).
• Server information, including the IP or host name of the Server, as well as the Port.

• BaseDN: This will limit the scope of LDAP searches to the height of the distinguished name provided.

  Note: Specifying a narrow BaseDN may greatly increase performance; for example, cn=users,dc=domain will only return results contained within cn=users and its children.

You can then follow the steps below to use the Data Explorer to create a FireDAC connection to LDAP objects.

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 LDAP.

Create VCL Applications with Connectivity to LDAP Objects

Follow the procedure below to start executing queries to LDAP objects 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 LDAP objects.
   • 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 Id, LogonCount FROM User
   • 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.