Iphone – how to convert NSData to char array containing hexa values

iphone

i am receiving NSData by following method

     - (void)socket:(GCDAsyncSocket *)sock didReadData:(NSData *)data withTag:(long)tag

server send data in follwing format

                 04 01 00

as hexa values. so now need to convert this data into char array so that i can access every pair separately
please help

Best Answer

You can go like this if you'd like to compare byte by byte:

    //NSData *test; // assume this is your NSData containing 0x04 0x01 0x00

    char *ptr = (void *)[test bytes]; // set a pointer to the beginning of your data bytes
    if(*ptr == 0x04) {
        NSLog(@"okay,.. got a 0x04");
    }
    ptr++; // go to the next byte
    if(*ptr == 0x01) {
        NSLog(@"okay,.. got a 0x01");
    }

hope that does work for you.

Related Solutions

Objective-c – Convert hex data string to NSData in Objective C (cocoa)

Code for hex in NSStrings like "00 05 22 1C EA 01 00 FF". 'command' is the hex NSString.

command = [command stringByReplacingOccurrencesOfString:@" " withString:@""];
NSMutableData *commandToSend= [[NSMutableData alloc] init];
unsigned char whole_byte;
char byte_chars[3] = {'\0','\0','\0'};
for (int i = 0; i < ([command length] / 2); i++) {
    byte_chars[0] = [command characterAtIndex:i*2];
    byte_chars[1] = [command characterAtIndex:i*2+1];
    whole_byte = strtol(byte_chars, NULL, 16);
    [commandToSend appendBytes:&whole_byte length:1]; 
}
NSLog(@"%@", commandToSend);

Ios – Convert NSData to byte array

Try this

NSData *imageData = UIImagePNGRepresentation(recipeImage.image);  
NSUInteger len = [imageData length];
Byte *byteData= (Byte*)malloc(len);
[imageData  getBytes:byteData length:len];

Best Answer

Related Solutions

Objective-c – Convert hex data string to NSData in Objective C (cocoa)

Ios – Convert NSData to byte array

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