This control allows me set the checkbox property to True / False. If the Checkbox property is set to true, the checkbox is displayed in the control and it allows the user to decide if the Value property will be populated or not and if the user wants to use the date in the query they are about to run against the DB. My question is, how can I check or uncheck the checkbox from within my code to set the checkbox at an appropriate default value at various instances the user is running the program? The checkbox property is only used to determine if the checkbox should be displayed or not.