获取字符串首字母

#import <Foundation/Foundation.h>

@interface NSString (SayHi)

- (void)sayHi;

//可以获取首字母,字符串

- (NSString *)firstCharactor;

@end

#import "NSString+SayHi.h"

@implementation NSString (SayHi)

- (void)sayHi

{

    NSLog(@"你好你是牛逼的字符串");

}

- (NSString *)firstCharactor

{

    return [[self substringToIndex:1] uppercaseString];

}

@end