oc 类型判断

#import <UIKit/UIKit.h>
#import "AppDelegate.h"

@interface A : NSObject

@end

@implementation A

@end

@interface AA : A

@end

@implementation AA

@end

@interface B : NSObject

@end

@implementation B

@end

int main(int argc, char * argv[]) {
    A *a=[[A alloc]init];
    NSLog(@"%d",[a isKindOfClass:[B class ] ]);//返回值1表示是这个类型，0不是这个类型
}