Custom format UK telephone numbers/UK post codes

Hi, I am really hoping someone can help me.

I would like help with a custom format for Excel 2003.

I need telephone numbers to be entered like this (one of three possible inputs)

0123 1234567 if area code is only 4 digits followed by 7 digits, (11 total)

01234 123456 if area code is 5 digits followed by 6 numbers, (11 total)

and if 01234 12345 if area code is 5 digits but only followed by 5, (10 total)

All three are possible options and I need to allow this so that when the numbers are entered like this: 01231234567 it changes to: 0123 1234567 etc.

I've tried doing this formula which I found in another thread: [>999999999]0000 0000000;[>99999999]00000 000000 obviously unsuccessfully, however the first part does work.

When I couldn't get it to work I have temporarily changed it to "[>99999999]00000 000000" so all area codes are 5 digits...but this isn't really what I need.

I am hoping also to make a spin off from this for UK post codes but I can not find a custom format which allows for letters and digits, the post codes aren't as complex, it's either NG1 1AB or NG12 1AB so not much variation...any help on that also would be welcome, I don't mind if custom format is not the way to go with this one.


Thank you in advance

duplicate with below again!

0123 1234567
01234 123456
how would any custom format know the difference? they could be equally be
01231 234567
0123 4123456

i dont think it can be done