Edit Box Character Test (Input Filter)

[Freddie Code]

I'm trying to filter the characters that are typed into an edit box. For example, I only want the characters A,B,C,D,E,F to be allowed to be typed into the box. Any other characters typed will not be displayed in the box. Does anyone know how to do this? Thanks, Freddie

[Prakash Nadar]

Basically you customise the edit control. Derive a class from the CEdit and listen to the keyboard inputs if they are not amoung the charecters that you want then ignore them. There are lot of these types of controls here in the codeproject. You can follow the link for CEdit on the leftside at www.codeproject.com

---

This space is empty.

[monrobot13]

Here's a quick and dirty implementation:

// in CMyEdit.h
afx_msg void OnChar (UINT nChar, UINT nRepCnt, UINT nFlags);
DECLAR_MESSAGE_MAP()

// in CMyEdit.cpp

BEGIN_MESSAGE_MAP(CMyEdit, CEdit)
ON_WM_CHAR ()
END_MESSAGE_MAP()

void CMyEdit::OnChar (UINT nChar, UINT nRepCnt, UINT nFlags)
{
int lwr = tolower (nChar);

if (lwr >= 'a' && lwr <= 'f' && lwr != '.' ||
    lwr == VK\_BACK || lwr == VK\_DELETE
   )
    CEdit::OnChar (nChar, nRepCnt, nFlags)

}

Then add a control variable for the editbox and in your .h file change it's type to CMyEdit instead of CEdit. Not the best way to do it, but you could get by with it. - Aaron