That's because your validation check requires at least one number to be present. If you select all, then type, Tk will first try to delete everything - however, an empty entry is invalid, so the deletion fails.

The fix is simple. Just change the first line of your sub to: 

return 0 if $_[0]=~/\D/;

[download]

Abigail

In reply to Re: Tk::Entry validate question by Abigail-II
in thread Tk::Entry validate question by Baboon

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