>Had a thought on this that I want to share. Beginning with VFP 6.0, validating data for objects became a whole lot easier with the _Access and _Assign events. Combined with the bitwise functions, it makes checking for a large number of properties a snap. The following is from my own work.
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>I had a situation where a large number of properties (over 20) had to be properly initialized prior to making some very complex calculations. By adding an _Assign method to each property, I was easily able to validate the incoming information. If the information was valid, I set a bit of an integer property to indicate that the data was valid. If it was invalid, I made sure that the bit was cleared. Each property was thus represented by a bit. Using BITAND() allowed me to easily test to make sure that all the necessary properties were properly initialized.


Good idea, George. It might be even easier to implement this idea in VFP 8 using BINDEVENT()function. Instead of creating separate _Assign methods one can bind the necessary properties to one custom check method, that fire whenever any bound property is changed and will validate all the properties.