FILTER_FLAG_IPV4 | FILTER_FLAG_IPV6) always seems to return false.You probably wouldn't need to combine these two because that's what the function does by default but I though't it important to add a note about this.I’ve been working on a fix to a system script that passes around and manipulates IP addresses.
by using the focus for validation it is too late to just return a boolean to cancel the edit because the entry is already editted.
To do validation with focus, if there is a problem you must actual modify the value.
By utilizing this service, companies can cross-reference the location of a visitor's IP address against other data points, including billing and shipping addresses, to prevent possible fraudulent transactions.
# Purpose: a part of a series of examples of Tk code validating # the input of a user.
I got a bit caught up in the differences between addresses from RFC4291 and the recommendations in RFC5952.
The prior allows for zero folding of single 16-bit 0 fields while the latter discourages this.
I clean things up a bit by using shell variables but the regex should be clear: Nothing earth shattering. To compensate for the larger addresses size when representing IPv6 addresses in text, the RFC recommends a canonical textual representation with rules that allow for compression (called “zero folding”).
Addresses represented in this compressed format are more difficult to validate with just one regex and the regex is much longer: #!
This is added to the flags passed with the | bitwise operator.
For example: From my own testing I have discovered that combining FILTER_FLAG_IPV4 and FILTER_FLAG_IPV6 (i.e.
While working on this and digging around the web I ran across some stuff that I think is worth sharing.