category_example_Objc_.h

#import <Foundation/Foundation.h>

@interface NSDate (Formatted)

- (NSString*)dateStringByFormatted:(NSString*)formate;

@end

category_example_Objc_.m

#import "NSDate+Formatted.h"

@implementation NSDate (Formatted)

- (NSString*)dateStringByFormatted:(NSString*)formate{
    if (self == nil || formate == nil) {
        return nil;
    }
    
    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
    [dateFormatter setDateFormat:formate];
    
    return [dateFormatter stringFromDate:self];
}

@end