Decode Base-64 encoded PNG in an NSString
I have some NSData
which is Base-64 encoded and I would like to decode it, I have seen an example that looks like this
NSData* myPNGData = [xmlString dataUsingEncoding:NSUTF8StringEncoding];
[Base64 initialize];
NSData *data = [Base64 decode:img];
cell.image.image = [UIImage imageWithData:myPNGData];
However this gives me a load of errors, I would like to know what to do in order to get this to work. Is there some type of file I need to import into my project or do I have to include a framework?
These are the errors I get
Use of undeclared identifier 'Base64'
Use of undeclared identifier 'Base64'
Use of undeclared identifier 'cell'
I have looked everywhere and cannot figure out what is the proper thing to do.
Solution 1:
You can decode a Base64 encoded string to NSData
:
-(NSData *)dataFromBase64EncodedString:(NSString *)string{
if (string.length > 0) {
//the iPhone has base 64 decoding built in but not obviously. The trick is to
//create a data url that's base 64 encoded and ask an NSData to load it.
NSString *data64URLString = [NSString stringWithFormat:@"data:;base64,%@", string];
NSData *data = [NSData dataWithContentsOfURL:[NSURL URLWithString:data64URLString]];
return data;
}
return nil;
}
Example use of above method to get an image from the Base64 string:
-(void)imageFromBase64EncodedString{
NSString *string = @""; // replace with encocded string
NSData *imageData = [self dataFromBase64EncodedString:string];
UIImage *myImage = [UIImage imageWithData:imageData];
// do something with image
}
Solution 2:
NSData Base64 library files will help you.
#import "NSData+Base64.h"
//Data from your string is decoded & converted to UIImage
UIImage *image = [UIImage imageWithData:[NSData
dataFromBase64String:strData]];
Hope it helps
Swift 3 Version
It's pretty much the same
//Create your NSData object
let data = NSData(base64Encoded: "yourStringData", options: NSData.Base64DecodingOptions.ignoreUnknownCharacters)
//And then just create a new image based on the data object
let image = UIImage(data: data as! Data)
Swift 2.3 Version
//Create your NSData object
let data = NSData(base64EncodedString: "yourStringData", options: .IgnoreUnknownCharacters)
//And then just create a new image based on the data object
let image = UIImage(data: data!)
Solution 3:
//retrieve your string
NSString *string64 = //... some string base 64 encoded
//convert your string to data
NSData *data = [[NSData alloc] initWithBase64EncodedString:string64 options:NSDataBase64DecodingIgnoreUnknownCharacters];
//initiate image from data
UIImage *captcha_image = [[UIImage alloc] initWithData:data];
Solution 4:
NSString *base64String=@"............";
NSData* data = [[NSData alloc] initWithBase64EncodedString:base64String options:0];
UIImage* img = [UIImage imageWithData:data];
//imageview is the refrence outlet of image view
self.imageview.image=img;