I have just tried implementing a class where numerous length/count properties, etc. are uint instead of int. However, while doing so I noticed that it's actually painful to do so, like as if no one actually wants to do that.
Nearly everything that hands out an integral type returns an int, therefore requiring casts in several points. I wanted to construct a StringBuffer with its buffer length defaulted to one of the fields in that class. Requires a cast too.
So I wondered whether I should just revert to int here. I'm certainly not using the entire range anyway. I just thought since what I'm dealing with there simply can't be negative (if it was, it'd be an error) it'd be a nice idea to actually use uint.
P.S.: I saw this question and this at least explains why the framework itself always uses int but even in own code it's actually cumbersome to stick to uint which makes me think it apparently isn't really wanted.
While strictly you should use uint for variables that hold non-negative integer you have come across one of reasons why it's not always practicable.
In this case I don't think the reduction in readability that comes with having to do casts is worth it.