NSData to display as a string

Question

Hello all, this is my first post. I am building an iPhone app and stuck with the following:

unsigned char hashedChars[32];
CC_SHA256([inputString UTF8String], [inputString lengthOfBytesUsingEncoding:NSASCIIStringEncoding], hashedChars);
NSData *hashedData = [NSData dataWithBytes:hashedChars length:32];
NSLog(@"hashedData = %@", hashedData);

The log is showing like:

hashedData = <abcdefgh abcdefgh abcdefgh abcdefgh abcdefgh abcdefgh abcdefgh abcdefgh>

• note hashedData is NSData, not NSString

But what I need is to convert hashedData into NSString that looks like:

NSString *someString = @"abcdefghabcdefghabcdefghabcdefghabcdefghabcdefghabcdefghabcdefgh";

So basically the result needs to be like hashedData except I don't want the angle brackets and spaces in between.

Any help is much appreciated.

Answer 1

Define an NSCharacterSet that contains the offending characters then filter your string using -stringByTrimmingCharactersInSet:.

Answer 2

Use the NSString initWithData:encoding: method.

NSString *someString = [[NSString alloc] initWithData:hashedData encoding:NSASCIIStringEncoding];

(edit to respond to your comment:)

In that case, Joshua's answer does help:

NSCharacterSet *charsToRemove = [NSCharacterSet characterSetWithCharactersInString:@"< >"];
NSString *someString = [[hashedData description] stringByTrimmingCharactersInSet:charsToRemove];

Answer 3

I have found the solution and I think I was being stupid.

Basically all I had to do is:

NSString *someString = [NSString stringWithFormat:@"%@", hashedData]; //forcing the NSData to become NSString

Once again thank you to all who tried to help. Much appreciated.