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Gestionnaire d'écran & Écrans
>I have built a form with the form builder and initially not selected a certain field from the table. On second thoughts I changed my mind and added the field to the form. The textbox that I have added looks the same as the rest(embossed) but in the property sheet(Class) it just says "textbox" and not "embossed". Neither is the class library the same. (None and C:\Program_Files\...)
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>Should I worry about it or must I change it in "Map field type to classes" in the Data tab of the Project Manager?
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>Advice would be appreciated.
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>Petrus
The object that is of class "textbox" has a class library of "none" because "textbox" is a baseclass. Any class which is NOT a baseclass will have the file name of its class library stored in the property "classlibrary".
Therefore, "textbox" is a baseclass.
"embossedfield" is NOT a baseclass.
Someone took the baseclass "textbox" and subclassed it into a custom/hand made class called "embossedfield". Thus "embossedfield" and "textbox" ARE DIFFERENT.
If you examine the class definition of "embossedfield" you will see the differences are small.
To see how "embossedfield" will behave open up a "visual class library" called "wizstyle.vcx". Do a search to find out which directory "wizstyle.vcx" is in. Open up the class called "embossedfield". This custom or "hand made" class is just a subclass of the "textbox". There are very few differences between "embossedfield" class and the "textbox" class.
To understand how subclassing and other OO techniques work check out chapter 3
in the VFP manual and also try "tracing" in the tools menu to watch the program flow.
Good Luck, Dave
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