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Create custom CEdit controls that validate input as you type

Hi Experts,

I'm trying to extend CEdit so that I can modify its OnChar or OnKeyDown functions - so that I can perform input validation and not allow invalid input. However, I think I'm going about this all wrong - these functions are not being called for my subclass when I type keys as I expected. Am I right in assuming that member variables which are controls are not tied directly through my object? Everything in windows is a message right? Is there no way to go about this in a java-swing sort of way?

I've seen countless examples of how to do input validation with DDX and DDV calls - but I would much rather just create my own classes that already have all this behavior built into them - and have MFC use my classes and interact with them as objects...

Any suggestions or is this not possible with MFC?

Thanks,
Mike

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jkr

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krbatge

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ASKER CERTIFIED SOLUTION

krbatge

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mikexpert

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Hi krbatge,

I'm sorry for waiting so long with this.. I still haven't got this working. I did exactly as you said - but my onChar function doesn't get called. If I look in classwizard, my member variable is of type CFilteredEdit... (changed the name to CFilteredEdit from CValidatingEdit because I deleted CValidatingEdit after many tries...)

So I must still be missing something.. I've got a member variable tied to this control ID and it has a classwizard generated code snippet for OnChar like this:

void CFilteredEdit::OnChar(UINT nChar, UINT nRepCnt, UINT nFlags)
{
if(nChar!='a')
CEdit::OnChar(nChar, nRepCnt, nFlags);
}

the breakpoint on the if is never reached and I can type any characters...

Any ideas?
Thanks again!

Mike

mikexpert

ASKER

Also, I notice my CFilteredEdit class dosn't show up in ClassWizard....

mikexpert

ASKER

Yep - I realized the problem.... Starting fresh after a break from a problem does tend to help sometimes. Since my class wasn't recognized by ClassWizard, I created a new one and this one worked. So many thanks for your help everyone!

Mike