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copied!<p>Alright, I think I got a bit closer. However, I'm not quite there yet, since I ran into some "EXC_BAD_ACCESS" when converting data back to a new array.</p> <p>Let me share some code with you. The following is supposed to take care of converting the array to NSData, converting NSData to base64 and vice versa.</p> <pre><code>@interface NSArray (dataConversion) + (NSArray*) arrayWithData:(NSData*) data; - (NSData*) convertToData; @end @implementation NSArray (dataConversion) - (NSData*) convertToData { unsigned n= [self count]; NSMutableData* data = [NSMutableData dataWithLength: sizeof(unsigned)+ sizeof(id) *n]; unsigned* p = [data mutableBytes]; *p++= n; [self getObjects:(void*)p]; return data; } + (NSArray*) arrayWithData:(NSData*) data { unsigned* p = (unsigned*)[data bytes]; unsigned n = *p++; return [NSArray arrayWithObjects:(id*)p count:n]; } @end @interface NSData (MBBase64) + (id)dataWithBase64EncodedString:(NSString *)string; // Padding '=' characters are optional. Whitespace is ignored. - (NSString *)base64Encoding; @end static const char encodingTable[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; @implementation NSData (MBBase64) + (id)dataWithBase64EncodedString:(NSString *)string; { if (string == nil) [NSException raise:NSInvalidArgumentException format:nil]; if ([string length] == 0) return [NSData data]; static char *decodingTable = NULL; if (decodingTable == NULL) { decodingTable = malloc(256); if (decodingTable == NULL) return nil; memset(decodingTable, CHAR_MAX, 256); NSUInteger i; for (i = 0; i < 64; i++) decodingTable[(short)encodingTable[i]] = i; } const char *characters = [string cStringUsingEncoding:NSASCIIStringEncoding]; if (characters == NULL) // Not an ASCII string! return nil; char *bytes = malloc((([string length] + 3) / 4) * 3); if (bytes == NULL) return nil; NSUInteger length = 0; NSUInteger i = 0; while (YES) { char buffer[4]; short bufferLength; for (bufferLength = 0; bufferLength < 4; i++) { if (characters[i] == '\0') break; if (isspace(characters[i]) || characters[i] == '=') continue; buffer[bufferLength] = decodingTable[(short)characters[i]]; if (buffer[bufferLength++] == CHAR_MAX) // Illegal character! { free(bytes); return nil; } } if (bufferLength == 0) break; if (bufferLength == 1) // At least two characters are needed to produce one byte! { free(bytes); return nil; } // Decode the characters in the buffer to bytes. bytes[length++] = (buffer[0] << 2) | (buffer[1] >> 4); if (bufferLength > 2) bytes[length++] = (buffer[1] << 4) | (buffer[2] >> 2); if (bufferLength > 3) bytes[length++] = (buffer[2] << 6) | buffer[3]; } realloc(bytes, length); return [NSData dataWithBytesNoCopy:bytes length:length]; } - (NSString *)base64Encoding; { if ([self length] == 0) return @""; char *characters = malloc((([self length] + 2) / 3) * 4); if (characters == NULL) return nil; NSUInteger length = 0; NSUInteger i = 0; while (i < [self length]) { char buffer[3] = {0,0,0}; short bufferLength = 0; while (bufferLength < 3 && i < [self length]) buffer[bufferLength++] = ((char *)[self bytes])[i++]; // Encode the bytes in the buffer to four characters, including padding "=" characters if necessary. characters[length++] = encodingTable[(buffer[0] & 0xFC) >> 2]; characters[length++] = encodingTable[((buffer[0] & 0x03) << 4) | ((buffer[1] & 0xF0) >> 4)]; if (bufferLength > 1) characters[length++] = encodingTable[((buffer[1] & 0x0F) << 2) | ((buffer[2] & 0xC0) >> 6)]; else characters[length++] = '='; if (bufferLength > 2) characters[length++] = encodingTable[buffer[2] & 0x3F]; else characters[length++] = '='; } return [[[NSString alloc] initWithBytesNoCopy:characters length:length encoding:NSASCIIStringEncoding freeWhenDone:YES] autorelease]; } @end </code></pre> <p>Now, I use it like that:</p> <pre><code>NSData *messageData = [[NSArray arrayWithArray:myNSMutableArray] convertToData]; NSString *messageData = [messageData base64Encoding]; </code></pre> <p>messageData is the string I now send to my server. This works fine.</p> <p>Now the other way round:</p> <pre><code>NSData *arrayData = [NSData dataWithBase64EncodedString:serverResponseString]; //serverResponseString is the string returned from my server upon request NSMutableArray *newArray = [[NSMutableArray alloc] initWithArray:[NSArray arrayWithData:arrayData]]; //here it crashes and points to: "return [NSArray arrayWithObjects:(id*)p count:n];" </code></pre> <p>I'm either missing something here or completely off track. Any help appreciated. Thanks.</p>

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