Method-Swizz-ObjC

#import <objc/runtime.h>
#import <Foundation/Foundation.h>

@interface Encryption
- (id) myEncrypt: (NSString *) _secret;
@end


@implementation Encryption

+(void)load
{
        printf("Inside load function\n");
        if (self == [Encryption class]) {
                printf("inside if\n");
              //  self = [Encryption class];
                Method origMethod = class_getInstanceMethod(self,@selector(Encrypt:));
                Method newMethod  = class_getInstanceMethod(self,@selector(myEncrypt:));
                method_exchangeImplementations(origMethod,newMethod);
        }
        else
        printf("swizzling failed\n");
}

- (id) myEncrypt: (NSString *) _secret {
        printf("inside the new encryption\n");
   //     printf("Your Secrect was %s\n", [ _secret UTF8String ]);
        //*_secret = @"HELLO I AM MODIFIED";
   //     printf("The next text sent is %s",[ _secret UTF8String ]);
        return [self myEncrypt:_secret];
}

@end