This event is generated after the report's object is filled with the data, to which it is connected. It is convenient to use this event for analyzing either a DB field value, or an expression contained in the object. The fact is that this value is placed to the "Value" service variable, the value of which is available in this event only. So, having two "Text" objects with the [Table1."Field1"] and [ + 10] contents, it is convenient to analyze the value of these expressions referring to the "Value" variable:

if Value > 3000 then
Memo1.Color := clRed

instead of writing something like that:

if <Table1."Field1"> > 3000 then
Memo1.Color := clRed

Moreover, using of "Value" instead of an expression provides you with a possibility to write one multipurpose handler of the "OnAfterData" event, and to connect it to several objects.

One more thing is to be noted. If there are several expressions in an object (for example, [expr1] [expr2]) a value of the last expression is transferred to the "Value" variable.