Nope, never had to wear a uniform but I had friends who went to Catholic school and they had to wear uniforms so when we'd get off from school they always had to change before they could play. Honestly I wouldn't have minded wearing a uniform though, at least then I wouldn't have had to worry about what to wear. XD
my school was really strict with uniform policy (private, all-girl catholic school ahaha)
as well as our dress that looked like a candy wrapper with a big green bow at the collar (if i find a picture that will be easy to blur faces i'll add it), you could only have hair accessories that were the school colour (green) or like.... hair-coloured ones. we had white socks that could only be folded down once - not twice, and they couldn't be pulled up, they had to be folded once.
than standard australian uniform rules like no jewellery, makeup, nail polish, etc
tbh i loved having a uniform because i am super lazy, especially in the morning. i hated having to figure out what to wear when i was in university!
I've worn uniforms for all of my years in school so far because I have attended a private K-8 and high school. It was somewhat frustrating for me only because our K-8 was VERY strict (i.e: wear a certain type of shoe, no jewelry, you can only wear hair items with school colors in them), while 9-12 so far has been a bit less lenient (it doesn't have any of those rules). I do prefer the uniforms though because it's just less of a hassle.
I've never been to a school that made us wear uniforms. I live in the US, and most of the public schools (all I've ever been to) don't make us do that. Hell, my high school barely enforces the dress code!