Converting between NSData and base64 strings
What is the easiest and fastest code to do a conversion b开发者_如何学编程etween NSData
and a base64 string? I've read a bunch of solutions at SO and mostly they involve in adding another class etc. I found a great solution here but it's too complex.
Scroll down to the Conclusion section on the page you linked and download the provided NSData+Base64 files. Its the best solution I have seen so far and is incredibly easy to use. If you can learn anything about Cocoa, you can learn to use that project.
Example
NSString *originalString = [NSString stringWithFormat:@"test"];
NSData *data = [NSData dataFromBase64String:originalString];
NSLog([data base64EncodedString]);
The above will print out the original string after converting it to base64 and back to a normal unencoded string.
As of iOS 7, NSData
now directly provides this functionality with the new methods -base64EncodedDataWithOptions:
and -base64EncodedStringWithOptions:
. (The options let you specify that the string is/should be line-wrapped, the better to deal with email, and user-facing displays.)
You don't need any custom implementation. Creating base64 from NSData is shown in other answers. There is opposite direction. From Base64 string to NSData:
NSString *base64Encoded = @"some base64 string";
NSData *nsdataFromBase64String = [[NSData alloc] initWithBase64EncodedString:base64Encoded options:0];
I ended up using this same class as provided by SUDZC
implementation was easy first I did an import
#import "NSData+Base64.h"
then I was able to call my data.
NSData *data = [[NSData alloc] initWithData:[NSData dataWithBase64EncodedString:strData]];
Be aware that there are more Base64 formats.
For example JWTs use a URL safe format.
Or you may take a look to the (quite new) CryptoCompatibility sample project, I think there is a wrapper class for base64 operation. It is a MacOS sample but it uses the library libresolve.dylib with I think is available on iOS too (is see it at least here in iOS7).
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