Categories of IOS deep copy, NSArray, and NSDictionary)

Categories of IOS deep copy, NSArray, and NSDictionary)

Find a place for the difference between deep copy and shallow copy ....... The bottom is the NSArray and NSDictionary deep copy classification method.

Code used for common debugging in the Code: This log will only be printed during debugging and will not appear during release.

#ifdef DEBUG#ifndef DLog#   define DLog(fmt, ...) {NSLog((@"%s [Line %d] " fmt), __PRETTY_FUNCTION__, __LINE__, ##__VA_ARGS__);}#endif#ifndef ELog#   define ELog(err) {if(err) DLog(@"%@", err)}#endif#else#ifndef DLog#   define DLog(...)#endif#ifndef ELog#   define ELog(err)#endif#endif

The following two pieces of code are copied from the project.

SJDeepCopy. h file

#import 
 
  @interface NSArray (SJDeepCopy)- (NSArray*)deepCopy;- (NSMutableArray*) mutableDeepCopy;@end@interface NSDictionary (SJDeepCopy)- (NSDictionary*)deepCopy;- (NSMutableDictionary*)mutableDeepCopy;@end
 

SJDeepCopy. m file

#import "SJDeepCopy.h"@implementation NSArray (SJDeepCopy)- (NSArray*)deepCopy {    NSUInteger count = [self count];    id cArray[count];        for (NSUInteger i = 0; i < count; ++i) {        id obj = [self objectAtIndex:i];        if ([obj respondsToSelector:@selector(deepCopy)]) {            cArray[i] = [obj deepCopy];        }        else if ([obj respondsToSelector:@selector(copyWithZone:)]) {            cArray[i] = [obj copy];        }        else {            DLog(@"********Error:NSArray DeepCopy Failed!!! ********");            return nil;        }    }        NSArray *ret = [NSArray arrayWithObjects:cArray count:count];        return ret;}- (NSMutableArray*)mutableDeepCopy {    NSUInteger count = [self count];    id cArray[count];        for (NSUInteger i = 0; i < count; ++i) {        id obj = [self objectAtIndex:i];                // Try to do a deep mutable copy, if this object supports it        if ([obj respondsToSelector:@selector(mutableDeepCopy)]) {            cArray[i] = [obj mutableDeepCopy];        }        // Then try a shallow mutable copy, if the object supports that        else if ([obj respondsToSelector:@selector(mutableCopyWithZone:)]) {            cArray[i] = [obj mutableCopy];        }        else if ([obj respondsToSelector:@selector(copyWithZone:)]) {            cArray[i] = [obj copy];        }        else {            DLog(@"********Error:NSArray MutableDeepCopy Failed!!! ********");            return nil;        }    }        NSMutableArray *ret = [NSMutableArray arrayWithObjects:cArray count:count];    return ret;}@end@implementation NSDictionary (SJDeepCopy)- (NSDictionary*)deepCopy {    NSUInteger count = [self count];    id cObjects[count];    id cKeys[count];        NSEnumerator *e = [self keyEnumerator];    NSUInteger i = 0;    id thisKey;    while ((thisKey = [e nextObject]) != nil) {        id obj = [self objectForKey:thisKey];                if ([obj respondsToSelector:@selector(deepCopy)]) {            cObjects[i] = [obj deepCopy];        }        else if([obj respondsToSelector:@selector(copyWithZone:)]) {            cObjects[i] = [obj copy];        }        else {            DLog(@"********Error:NSDictionary DeepCopy Failed!!! ********")            return nil;        }                if ([thisKey respondsToSelector:@selector(deepCopy)]) {            cKeys[i] = [thisKey deepCopy];        }        else if ([thisKey respondsToSelector:@selector(copyWithZone:)]) {            cKeys[i] = [thisKey copy];        }        else {            DLog(@"********Error:NSDictionary Key DeepCopy Failed!!! ********")            return nil;        }                ++i;    }        NSDictionary *ret = [NSDictionary dictionaryWithObjects:cObjects forKeys:cKeys count:count];        return ret;}- (NSMutableDictionary*)mutableDeepCopy {    unsigned int count = [self count];    id cObjects[count];    id cKeys[count];        NSEnumerator *e = [self keyEnumerator];    unsigned int i = 0;    id thisKey;    while ((thisKey = [e nextObject]) != nil) {        id obj = [self objectForKey:thisKey];                // Try to do a deep mutable copy, if this object supports it        if ([obj respondsToSelector:@selector(mutableDeepCopy)]) {            cObjects[i] = [obj mutableDeepCopy];        }        // Then try a shallow mutable copy, if the object supports that        else if ([obj respondsToSelector:@selector(mutableCopyWithZone:)]) {            cObjects[i] = [obj mutableCopy];        }        else if ([obj respondsToSelector:@selector(copyWithZone:)]) {            cObjects[i] = [obj copy];        }        else {            DLog(@"********Error:NSDictionary MutableDeepCopy Failed!!! ********")            return nil;        }                // I don't think mutable keys make much sense, so just do an ordinary copy        if ([thisKey respondsToSelector:@selector(deepCopy)]) {            cKeys[i] = [thisKey deepCopy];        }        else if([thisKey respondsToSelector:@selector(copyWithZone:)]) {            cKeys[i] = [thisKey copy];        }        else {            return nil;        }                ++i;    }        NSMutableDictionary *ret = [NSMutableDictionary dictionaryWithObjects:cObjects forKeys:cKeys count:count];        return ret;}@end