how to decode UTF8 string in iphone - iphone

I want to decode an UT8 encoded string.
The input string is "øæ-test-2.txt"
and after decoding it should become
"øæ-test-2.txt"
I found many API to encode the NSString or NSData to UT8 (NSUTF8StringEncoding) but was not able to find the way to decode it.
What I have tried until now:-
NSString *str = [[NSString alloc] initWithUTF8String:[strToDecode cStringUsingEncoding:NSUTF8StringEncoding]];
AND
[strToDecode stringByReplacingPercentEscapesUsingEncoding:NSUTF8StringEncoding]
AND
[NSString stringWithUTF8String:[strToDecode cStringUsingEncoding:[NSString defaultCStringEncoding]]]
I have tried the same input string and I get the proper output in third party decoder.
But was not able to get success
Any hint in right direction would be highly appreciated.

I use this one.
NSString *encoded_string = #"ü";
const char *ch = [encoded_string cStringUsingEncoding:NSISOLatin1StringEncoding];
NSString *decode_string = [[NSString alloc]initWithCString:ch encoding:NSUTF8StringEncoding];
NSLog(#"%#",decode_String)

[NSString stringWithUTF8String:]

Related

iPhone: strange output when casting nsdata to nsstring

I get a NSData object in return after decrypting a payload with aes128:
NSData *returnData = [ciphertext AES128DecryptWithKey:keyData withIV:ivData];
I get the following hex output when i try to NSLog this:
<2db88b73 d84599a1 5779c736 09c975b7 92750cf2 d11cb41b 19f13781
4401bc57 b2ad96c8 402e3ccf 851c0219 00aec76b>
I then try to setting it as NSString:
[[NSString alloc] initWithData:returnData
encoding:NSUTF8StringEncoding];
When using NSLog() on the string i get "(null)" as output.
Can someone tell me why and where i should look for the problem?
Collided with the same issue some time ago, found the answer here.
If the data is not null-terminated, you should use -initWithData:encoding:
NSString* newStr = [[[NSString alloc] initWithData:theData
encoding:NSUTF8StringEncoding] autorelease];
If the data is null-terminated, you should instead use -stringWithUTF8String: to avoid the extra \0 at the end.
NSString* newStr = [NSString stringWithUTF8String:[theData bytes]];
(If you have ARC enabled, remove the -autorelease call.)

Can't convert nsurl into base 64

I am doing this way. but i am not getting where is wrong.
NSString *strUrl = [NSString stringWithFormat:#"https://play.google.com/stor/apps/details?id=com.ShiftSharerfree_new&feature=search_result#?t=W251bGwsMSwyLDEsImNvbS5TaGlmdFNoYXJlcmZyZWVfbmV3Il"];
NSString *originalString = [NSString stringWithFormat:#"%#", strUrl];
NSData *data = [NSData dataFromBase64String:originalString];
NSString *data = [base64 originalString];
NSLog(#"data:%#", data);//[data base64EncodedString]);
Please guide me in above.
Perhaps you need a base64 conversion library, as mentioned here:
Convert between UIImage and Base64 string
I had a similar error with code for converting images to base64, using [base64 encode...] calls.
the first thing i'd noted is that the NSData and the NSString have the same name. Could this be the error?

How to Convert NSData to NSString

I know this has been asked quite before, and I already followed couple of approaches, but they don't work.
Following is what I already tried:
NSString *newStr = [NSString stringWithUTF8String:[responseData bytes]];
NSString *newStr = [NSString stringWithFormat:#"%.*s", [responseData length], [responseData bytes]];
None of them works. In 1st case, it fills newStr with null. In 2nd, it fills with junk characters. I know from debugger log (po responseData) that I get valid response which is like bbbbbb 00 bbbbbb. [server sends them as byte array]
What to do?
EDIT:
I am receiving this data from http request response - using ASIHTTPRequest library, in case anybody can help on that line.
Try this,
NSData *responseData; [Initialize it]
NSString *receivedDataString = [[NSString alloc] initWithData:responseData encoding:NSUTF8StringEncoding];
NSLog(#"%#",receivedDataString);
Please try following code
NSString *string = [[[NSString alloc] initWithData: responseData.bytes encoding:NSUTF8StringEncoding] autorelease];
You can use this code lines
NSString *str=[[NSString alloc] initWithBytes:data1.bytes length:data1.length encoding:NSUTF8StringEncoding];
I am posting this for records sake because I found a duplicate and voting to close this down.
Actually what I am receiving is a stream of bytes represented as hex, and all the answers indicated do not work. Only [NSData description] gave me true data, which is something I can't use because it is intended for debugging.
Finally I tried the solution given here, and I get what I want.
Thanks to all for trying to help out.
NSString *image1Data = [[NSData dataWithData:myData] encodeBase64ForData];
But for this, you have to use NSData+Base64Additions class.
Use following way
NSString *dC_Str = [[NSString alloc] initWithData:decryPtd_data encoding:NSASCIIStringEncoding] ;

NSString like '\uf003" replace '\' with some other string in in obj c

i need to send smiley to other user through iphone app ,so i need to replace \ string with some unique string in obj c.
here if your string is #"\ud83d\ude04" then it is give error "Invalid Character" so put this ' special character and then use it ..
NSString *str = #"\'ud83d\'ude04";//// here if your string is #"\ud83d\ude04" then it is give error "Invalid Character" so put this ' special character and then use it
NSString *smileWithString = [str stringByReplacingOccurrencesOfString:#"\'" withString:#":)"];
[smileWithString retain];
NSLog(#"\n\n SmileString %# Str %#",smileWithString);
Update:
Here’s how to convert NSString to NSData – it’s really simple:
NSString *myString = #"Some String";
NSData *myData = [myString dataUsingEncoding:NSUTF8StringEncoding];
And what about the reverse conversion, i.e. how to convert NSData to NSString? Here’s one quick way:
NSString *myString = [NSString stringWithFormat:#"%.*s",[myData length], [myData bytes]];
Use encoding of NSString and when need to use or show string decode it.
Refer base64-encoding link.
Your looking for stringByReplacingOccurrencesOfString that should do the trick.
NSString *newString = [oldString stringByReplacingOccurrencesOfString:#"\" withString:#"uniqueString"];

how to convert NSString encoding to UTF8

I have done something like:
NSData *dt = [mystr dataUsingEncoding:NSWindowsCP1251StringEncoding];
NSString *str = [NSString alloc] initWithData:dt encoding:NSUTF8StringEncoding];
then NSLog(#"%#", str);
However, if 'mystr' is english then the NSLog would print it as is, but if mystr is Arabic (for ex.) NSLog will not print anything, so how can i change the encoding of mystr to UTF8 ?
thank you in advance.
Your first line creates some data that is in cp1251 encoding. Your second line says "read this data into a string, assuming that the bytes represent a UTF8 encoded string". But because the bytes represent a cp1251 encoded string, that's not likely to work very well.
NSString represents an ordered collection of characters. Internally it uses some encoding to store these characters in memory, but its interface provides an encoding-independent access to the string and you can therefore consider NSString to be encoding-agnostic. If what you want is a collection of bytes that represent the string in UTF8 encoding, then you don't want an NSString. You want to get an NSString to emit such a collection of bytes, perhaps using the -dataUsingEncoding: method you've already found.
Try this one
NSString *s = #"Some string";
const char *c = [s UTF8String];
import
#import "NSString+URLEncoding.h" and
#import "NSString+URLEncoding.m" files
after that where u r doing encode write in .h file this method
-(NSString *)urlEncodeUsingEncoding:(NSStringEncoding)encoding;
after that write in .m file method implementation
-(NSString *)urlEncodeUsingEncoding:(NSStringEncoding)encoding
{
return (NSString *)CFBridgingRelease(CFURLCreateStringByAddingPercentEscapes(NULL,
(CFStringRef)self,
NULL,
(CFStringRef)#"!*'\"();:#&=+$,/?%#[]% ",
CFStringConvertNSStringEncodingToEncoding(encoding)));
}
after that use like this
NSString *keyword=#"sample text";
here pass ur string whatever
NSString *url = [NSString stringWithFormat:#"%#",[keyword urlEncodeUsingEncoding:NSUTF8StringEncoding]];
NSLog(#"%#",url);
Did you try [mystr UTF8String] ? This returns a char *
You can try this
1) NSString to NSData(NSWindowsCP1251StringEncoding
NSString *text=#"This is Sample Text Conversion.....";
NSData *data=[text dataUsingEncoding:NSWindowsCP1251StringEncoding];
2)Revers process.
NSString *textRev=[[NSString alloc]initWithData:data encoding:NSWindowsCP1251StringEncoding];
NSLog(#" Actual String.. %#",textRev);