objc警告:"从指针目标类型中丢弃限定符"

Ste*_*ion 11 iphone cocoa objective-c

编译时:

char *str = [[NSString stringWithFormat:@"%i days and %i hours", days, hours] UTF8String];
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我收到这个警告:

initialization discards qualifiers from pointer target type
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我怎么摆脱它?

Jen*_*ton 27

你缺少的资格赛是const.-UTF8String返回一个const char *,所以str也应该声明const char *.