I changed the colour of editor's background to black,so i can't see the caret.
Then I changed the colour of caret to white.
so the colour of caret becomes white.
but when i used a code auto compelete ,the colour of caret becomes red ,then black.
I can't see it again ..
I'm sorry .
but after I restarted the C::B,
The question is disappeared.
that means the cursors always keep it's colour with white.