How to Control a field based upon the value of another field

[guest]

How to enable or disable a field, say [age] based upon the entry of another field, say [sex] in the same form?

[james]

On the AfterUpdate Event of [sex], put the code

If (Me![sex].Value = "A") Or (Me![sex].Value = "B")Then
Me![age].Enabled = True
Else
Me![age].Enabled = False
End IF


And to be sure it's disabled when the form opens, put
Me![age].Enabled = False on the OnOpen event.