I need to decode a base 64 string. To do so I use the folowing code :
// Get the base 64 string vector.
NSString *vector64String = insertRequestDictionnary[#"check"];
// Decode the base 64 string into data.
NSData *vector64Data = [NSData dataFromBase64String: vector64String];
// Get the string from decoded data.
NSString *decodeVector = [[NSString alloc] initWithData: vector64Data
encoding: NSUTF8StringEncoding];
..But every time i get a nil string (decodeVector).
I check with this website (http://www.base64decode.org/), my first string (vector64string) is base 64. For example : "h508ILubppN1xLpmXWLfnw==" gives "< uĺf]bߟ"
Thanks.
Not all data is an NSUTF8String. The point of Base64 to to create a string representation of data that is not naturally a string.
NSString *vector64String = #"h508ILubppN1xLpmXWLfnw==";
NSData *vector64Data = [[NSData alloc] initWithBase64EncodedString:vector64String options:0];
NSLog(#"vector64Data: %#", vector64Data);
NSLog output:
vector64Data: <879d3c20 bb9ba693 75c4ba66 5d62df9f>
vector64Data is the decoded base64 string.
The vector64Data is not a UTF8 string, it is just data.
Related
I've got this:
<53657269 616c3a20 39303030 30303138 3b4d6f64 656c3a20 32323031 3b466972 6d776172 653a2030 3431353b 4c696272 6172793a 20535444 30363132 3b566f69 63653a20 4d31303b 546f7765 723a2059 65733b52 65636f72 643a2059 65733b44 69616c3a 204e6f3b 554f7074 733a2031 39383b46 756e6374 696f6e73 3a205245 44411034 424c5545 1011546f 6c6c0118 48796d6e a003466e 63351066 666f6f64 10556261 636f0000 746f6173 10253b4c 6162656c 733a2042 4c554542 4c554523 466e6338 544f4153 54455223 466e6337 4241434f 4e23466e 63354c41 50544f50 53235245 44415445 58415323 466e6336 42524943 4b532374 6f617354 4f415354 45522362 61636f42 41434f4e 23666f6f 64424143 4f4e3b4d 696c5665 723a2035 2e302e36 2e313b4c 6f67696e 3a205965 73>
I'm using this to convert to a NSString:
NSString *info = [[NSString alloc] initWithData:data encoding:NSASCIIStringEncoding];
My output is:
Serial: 90000018;Model: 2201;Firmware: 0415;Library: STD0612;Voice: M10;Tower: Yes;Record: Yes;Dial: No;UOpts: 198;Functions: REDA4BLUETollHymn Fnc5ffoodUbaco
If you convert the entire set you get a lot more than what is showing up in the string. Why is it cutting it short in the encoding?
Quickly converting with readily available encoders online you get the full conversion:
Serial: 90000018;Model: 2201;Firmware: 0415;Library: STD0612;Voice: M10;Tower: Yes;Record: Yes;Dial: No;UOpts: 198;Functions: REDA4BLUETollHymn Fnc5ffoodUbacotoas%;Labels: BLUEBLUE#Fnc8TOASTER#Fnc7BACON#Fnc5LAPTOPS#REDATEXAS#Fnc6BRICKS#toasTOASTER#bacoBACON#foodBACON;MilVer: 5.0.6.1;Login: Yes
Why is NSString *info = [[NSString alloc] initWithData:data encoding:NSASCIIStringEncoding]; only writing about half to the string?
I suspect that it's converting the whole string, but the mechanism you're using to examine it is truncating it. It looks like your ASCII-encoded data has embedded null characters in it. NSString is perfectly capable of holding embedded null characters, but anything which converts to a C-style string will stop processing after it hits one of those.
What do you get if you post-process your string using the following?
unichar nullUnichar = 0;
NSString* nullCharString = [[NSString alloc] initWithCharacters:&nullUnichar length:1];
info = [info stringByReplacingOccurrencesOfString:nullCharString withString:#"\\x00"];
I am writing a code that will convert the Unicode to tibetan string. Strangely the code give right conversion on some Unicode while give null while converting Unicode to NSString in iOS using Objective-C.
My unicode is
cellName = "\U0f56\U0f7c\U0f51\U0f0d";
cellSubtitle = "\U0f56\U0f7c\U0f51\U0f0b\U0f62\U0f72\U0f42\U0f66\U0f0b\U0f60\U0f51\U0f74\U0f66\U0f0b\U0f66\U0fa1\U0f7c\U0f51\U0f0b\U0f40\U0fb1\U0f72\U0f0b\U0f61\U0f74\U0f63\U0f0b\U0f42\U0fb2\U0f74\U0f0d \U0f66\U0f9f\U0f7c\U0f51\U0f0b\U0f58\U0f44\U0f60\U0f0b\U0f62\U0f72\U0f66\U0f0b\U0f66\U0f90\U0f7c\U0f62\U0f0b\U0f42\U0f66\U0f74\U0f58\U0f0b\U0f51\U0f44\U0f0c\U0f0d \U0f56\U0f62\U0f0b\U0f51\U0f56\U0f74\U0f66\U0f0b\U0f42\U0f59\U0f44\U0f0b\U0f62\U0f74\U0f0b\U0f56\U0f5e\U0f72\U0f0d \U0f66\U0fa8\U0f51\U0f0b\U0f58\U0f51\U0f7c\U0f0b\U0f41\U0f58\U0f66\U0f0b\U0f66\U0f92\U0f44\U0f0b\U0f51\U0fb2\U0f74\U0f42\U0f0b\U0f56\U0f45\U0f66\U0f0b\U0f66\U0f7c\U0f0d \U0f0d";
and the text conversion is
cellName = "བོད།";
cellSubtitle = "བོད་རིགས་འདུས་སྡོད་ཀྱི་ཡུལ་གྲུ། སྟོད་མངའ་རིས་སྐོར་གསུམ་དང༌། བར་དབུས་གཙང་རུ་བཞི། སྨད་མདོ་ཁམས་སྒང་དྲུག་བཅས་སོ། །";
for the unicode
cellName = "\U0f46\U0f74\U0f44\U0f0b\U0f0d";
cellSubtitle = "(\U0f62\U0f92\U0fb1\U0f53\U0f0b\U0f5a\U0f72\U0f42) \U0f21 \U0f46\U0f7a\U0f0b\U0f56\U0f60\U0f72\U0f0b\U0f63\U0fa1\U0f7c\U0f42\U0f0b\U0f5f\U0fb3\U0f0d \U0f56\U0f7c\U0f44\U0f66\U0f0b\U0f5a\U0f7c\U0f51\U0f0b\U0f51\U0f44\U0f0b\U0f62\U0f92\U0fb1\U0f0b\U0f41\U0fb1\U0f7c\U0f53\U0f0b\U0f66\U0f7c\U0f42\U0f66\U0f0b\U0f63\U0f9f\U0f7c\U0f66\U0f0b\U0f66\U0f0b\U0f63\U0f9f\U0f7c\U0f66\U0f0b\U0f60\U0f47\U0f7c\U0f42\U0f0b\U0f42\U0f72\U0f0b\U0f66\U0f92\U0f7c\U0f0b\U0f53\U0f66\U0f0b\U0f49\U0f74\U0f44\U0f0b\U0f44\U0f74\U0f0b\U0f59\U0f58\U0f0b\U0f63\U0f66\U0f0b\U0f5f\U0f72\U0f53\U0f0b\U0f58\U0f7a\U0f51\U0f0b\U0f54\U0f60\U0f72\U0f0b\U0f51\U0f7c\U0f53\U0f0b\U0f4f\U0f7a\U0f0d \n \U0f51\U0f54\U0f7a\U0f62\U0f0b\U0f53\U0f0d \U0f41\U0f44\U0f0b\U0f46\U0f74\U0f44\U0f0b\U0f0d \U0f5e\U0f72\U0f44\U0f0b\U0f46\U0f74\U0f44\U0f0b\U0f0d \U0f46\U0f74\U0f0b\U0f56\U0f7c\U0f0b\U0f46\U0f74\U0f44\U0f0b\U0f46\U0f74\U0f44\U0f0b\U0f0d \U0f51\U0f40\U0f62\U0f0b\U0f61\U0f7c\U0f63\U0f0b\U0f46\U0f74\U0f44\U0f0b\U0f56\U0f0b\U0f5e\U0f7a\U0f66\U0f0b\U0f54\U0f0b\U0f63\U0f9f\U0f0b\U0f56\U0f74\U0f0d \n2. \U0f53\U0f0b\U0f5a\U0f7c\U0f51\U0f0b\U0f42\U0f5e\U0f7c\U0f53\U0f0b\U0f54\U0f60\U0f72\U0f0b\U0f51\U0f7c\U0f53\U0f0b\U0f4f\U0f7a\U0f0d \n \U0f51\U0f54\U0f7a\U0f62\U0f0b\U0f53\U0f0d \U0f53\U0f74\U0f0b\U0f56\U0f7c\U0f0b\U0f53\U0f72\U0f0b\U0f55\U0f74\U0f0b\U0f56\U0f7c\U0f0b\U0f63\U0f66\U0f0b\U0f46\U0f74\U0f44\U0f0b\U0f0d \U0f46\U0f74\U0f44\U0f0b\U0f44\U0f74\U0f60\U0f72\U0f0b\U0f51\U0f74\U0f66\U0f0d \U0f55\U0f74\U0f0b\U0f56\U0f7c\U0f0b\U0f63\U0f66\U0f0b\U0f53\U0f74\U0f0b\U0f56\U0f7c\U0f0b\U0f46\U0f74\U0f44\U0f0b\U0f0d \U0f56\U0fb1\U0f72\U0f66\U0f0b\U0f54\U0f0b\U0f46\U0f74\U0f44\U0f0b\U0f56\U0f0d \U0f56\U0f74\U0f0b\U0f46\U0f74\U0f44\U0f0b\U0f56\U0f0b\U0f5e\U0f7a\U0f66\U0f0b\U0f54\U0f0b\U0f63\U0f9f\U0f0b\U0f56\U0f74\U0f0d3. \U0f51\U0f58\U0f53\U0f0b\U0f54\U0f60\U0f58\U0f0b\U0f5e\U0f53\U0f0b\U0f54\U0f60\U0f72\U0f0b\U0f51\U0f7c\U0f53\U0f0b\U0f4f\U0f7a\U0f0d \U0f66\U0f7a\U0f58\U0f66\U0f0b\U0f46\U0f74\U0f44\U0f0b\U0f0d \U0f49\U0f58\U0f0b\U0f46\U0f74\U0f44\U0f0b\U0f0d \U0f56\U0fb3\U0f7c\U0f0b\U0f46\U0f74\U0f44\U0f0b\U0f0d \U0f40\U0fb3\U0f51\U0f0b\U0f46\U0f74\U0f44\U0f0b\U0f5e\U0f7a\U0f66\U0f0b\U0f54\U0f0b\U0f63\U0f9f\U0f0b\U0f56\U0f74\U0f0d";
it gives me null value
And I am using this code for the conversion
NSData *data2 = [stringJoinedByNewLines2 dataUsingEncoding:NSUTF8StringEncoding];
NSString *decodevalue2 = [[NSString alloc] initWithData:data2 encoding:NSNonLossyASCIIStringEncoding];
I have a unicode string as
{\rtf1\ansi\ansicpg1252\cocoartf1265
{\fonttbl\f0\fswiss\fcharset0 Helvetica;\f1\fnil\fcharset0 LucidaGrande;}
{\colortbl;\red255\green255\blue255;}
{\*\listtable{\list\listtemplateid1\listhybrid{\listlevel\levelnfc23\levelnfcn23\leveljc0\leveljcn0\levelfollow0\levelstartat1\levelspace360\levelindent0{\*\levelmarker \{check\}}{\leveltext\leveltemplateid1\'01\uc0\u10003 ;}{\levelnumbers;}\fi-360\li720\lin720 }{\listname ;}\listid1}}
{\*\listoverridetable{\listoverride\listid1\listoverridecount0\ls1}}
\paperw11900\paperh16840\margl1440\margr1440\vieww22880\viewh16200\viewkind0
\pard\li720\fi-720\pardirnatural
\ls1\ilvl0
\f0\fs24 \cf0 {\listtext
\f1 \uc0\u10003
\f0 }One\
{\listtext
\f1 \uc0\u10003
\f0 }Two\
}
Here i have unicode data \u10003 which is equivalent to "✓" characters. I have used
[NSString stringWithCharacters:"\u10003" length:NSUTF16StringEncoding] which is throwing compilation error. Please let me know how to convert these unicode characters to "✓".
Regards,
Boom
I have same for problem and the following code solve my issue
For Encode
NSData *dataenc = [yourtext dataUsingEncoding:NSNonLossyASCIIStringEncoding];
NSString *encodevalue = [[NSString alloc]initWithData:dataenc encoding:NSUTF8StringEncoding];
For decode
NSData *data = [yourtext dataUsingEncoding:NSUTF8StringEncoding];
NSString *decodevalue = [[NSString alloc] initWithData:data encoding:NSNonLossyASCIIStringEncoding];
Thanks
I have used below code to convert a Uniode string to NSString. This should work fine.
NSData *unicodedStringData =
[unicodedString dataUsingEncoding:NSUTF8StringEncoding];
NSString *emojiStringValue =
[[NSString alloc] initWithData:unicodedStringData encoding:NSNonLossyASCIIStringEncoding];
In Swift 4
let emoji = "😃"
let unicodedData = emoji.data(using: String.Encoding.utf8, allowLossyConversion: true)
let emojiString = String(data: unicodedData!, encoding: String.Encoding.utf8)
I assume that:
You are reading this RTF data from a file or other external source.
You are parsing it yourself (not using, say, AppKit's built-in RTF parser).
You have a reason why you're parsing it yourself, and that reason isn't “wait, AppKit has this built in?”.
You have come upon \u… in the input you're parsing and need to convert that to a character for further handling and/or inclusion in the output text.
You have ruled out \uc, which is a different thing (it specifies the number of non-Unicode bytes that follow the \u… sequence, if I understood the RTF spec correctly).
\u is followed by hexadecimal digits. You need to parse those to a number; that number is the Unicode code point number for the character the sequence represents. You then need to create an NSString containing that character.
If you're using NSScanner to parse the input, then (assuming you have already scanned past the \u itself) you can simply ask the scanner to scanHexInt:. Pass a pointer to an unsigned int variable.
If you're not using NSScanner, do whatever makes sense for however you're parsing it. For example, if you've converted the RTF data to a C string and are reading through it yourself, you'll want to use strtoul to parse the hex number. It'll interpret the number in whatever base you specify (in this case, 16) and then put the pointer to the next character wherever you want it.
Your unsigned int or unsigned long variable will then contain the Unicode code point value for the specified character. In the example from your question, that will be 0x10003, or U+10003.
Now, for most characters, you could simply assign that over to a unichar variable and create an NSString from that. That won't work here: unichars only go up to 0xFFFF, and this code point is higher than that (in technical terms, it's outside the Basic Multilingual Plane).
Fortunately, *CF*String has a function to help you:
unsigned int codePoint = /*…*/;
unichar characters[2];
NSUInteger numCharacters = 0;
if (CFStringGetSurrogatePairForLongCharacter(codePoint, characters)) {
numCharacters = 2;
} else {
characters[0] = codePoint;
numCharacters = 1;
}
You can then use stringWithCharacters:length: to create an NSString from this array of 16-bit characters.
Use this:
NSString *myUnicodeString = #"\u10003";
Thanks to modern Objective C.
Let me know if its not what you want.
NSString *strUnicodeString = "\u2714";
NSData *unicodedStringData = [strUnicodeString dataUsingEncoding:NSUTF8StringEncoding];
NSString *emojiStringValue = [[NSString alloc] initWithData:unicodedStringData encoding:NSUTF8StringEncoding];
I'm trying to convert this :
NSString *encodedString = #"Les Profs (Comédie)"
into another NSSting in unicode :
NSString *decodedString = #"Les Profs (Comédie)"
I can't figure out how to do that easily...
Thanks in advance !
Your encoded string is containing html entities. You need to convert them to their unicode representation to get the required decoded string.
For conversion you can use following NSString extention
http://code.google.com/p/google-toolbox-for-mac/source/browse/trunk/Foundation/GTMNSString%2BHTML.h
http://code.google.com/p/google-toolbox-for-mac/source/browse/trunk/Foundation/GTMNSString%2BHTML.m
Here's how u will decode the string then
decodedStr = [encodedStr gtm_stringByUnescapingFromHTML];
CFStringTransform is the Core Foundation function that gives you what you need.
I have UTF-8 encoded NSData from windows server and I want to convert it to NSString for iPhone. Since data contains characters (like a degree symbol) which have different values on both platforms, how do I convert data to string?
If the data is not null-terminated, you should use -initWithData:encoding:
NSString* newStr = [[NSString alloc] initWithData:theData encoding:NSUTF8StringEncoding];
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]];
(Note that if the input is not properly UTF-8-encoded, you will get nil.)
Swift variant:
let newStr = String(data: data, encoding: .utf8)
// note that `newStr` is a `String?`, not a `String`.
If the data is null-terminated, you could go though the safe way which is remove the that null character, or the unsafe way similar to the Objective-C version above.
// safe way, provided data is \0-terminated
let newStr1 = String(data: data.subdata(in: 0 ..< data.count - 1), encoding: .utf8)
// unsafe way, provided data is \0-terminated
let newStr2 = data.withUnsafeBytes(String.init(utf8String:))
You could call this method
+(id)stringWithUTF8String:(const char *)bytes.
I humbly submit a category to make this less annoying:
#interface NSData (EasyUTF8)
// Safely decode the bytes into a UTF8 string
- (NSString *)asUTF8String;
#end
and
#implementation NSData (EasyUTF8)
- (NSString *)asUTF8String {
return [[NSString alloc] initWithData:self encoding:NSUTF8StringEncoding];
}
#end
(Note that if you're not using ARC you'll need an autorelease there.)
Now instead of the appallingly verbose:
NSData *data = ...
[[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
You can do:
NSData *data = ...
[data asUTF8String];
The Swift version from String to Data and back to String:
Xcode 10.1 • Swift 4.2.1
extension Data {
var string: String? {
return String(data: self, encoding: .utf8)
}
}
extension StringProtocol {
var data: Data {
return Data(utf8)
}
}
extension String {
var base64Decoded: Data? {
return Data(base64Encoded: self)
}
}
Playground
let string = "Hello World" // "Hello World"
let stringData = string.data // 11 bytes
let base64EncodedString = stringData.base64EncodedString() // "SGVsbG8gV29ybGQ="
let stringFromData = stringData.string // "Hello World"
let base64String = "SGVsbG8gV29ybGQ="
if let data = base64String.base64Decoded {
print(data) // 11 bytes
print(data.base64EncodedString()) // "SGVsbG8gV29ybGQ="
print(data.string ?? "nil") // "Hello World"
}
let stringWithAccent = "Olá Mundo" // "Olá Mundo"
print(stringWithAccent.count) // "9"
let stringWithAccentData = stringWithAccent.data // "10 bytes" note: an extra byte for the acute accent
let stringWithAccentFromData = stringWithAccentData.string // "Olá Mundo\n"
Sometimes, the methods in the other answers don't work. In my case, I'm generating a signature with my RSA private key and the result is NSData. I found that this seems to work:
Objective-C
NSData *signature;
NSString *signatureString = [signature base64EncodedStringWithOptions:0];
Swift
let signatureString = signature.base64EncodedStringWithOptions(nil)
Just to summarize, here's a complete answer, that worked for me.
My problem was that when I used
[NSString stringWithUTF8String:(char *)data.bytes];
The string I got was unpredictable: Around 70% it did contain the expected value, but too often it resulted with Null or even worse: garbaged at the end of the string.
After some digging I switched to
[[NSString alloc] initWithBytes:(char *)data.bytes length:data.length encoding:NSUTF8StringEncoding];
And got the expected result every time.
With Swift 5, you can use String's init(data:encoding:) initializer in order to convert a Data instance into a String instance using UTF-8. init(data:encoding:) has the following declaration:
init?(data: Data, encoding: String.Encoding)
Returns a String initialized by converting given data into Unicode characters using a given encoding.
The following Playground code shows how to use it:
import Foundation
let json = """
{
"firstName" : "John",
"lastName" : "Doe"
}
"""
let data = json.data(using: String.Encoding.utf8)!
let optionalString = String(data: data, encoding: String.Encoding.utf8)
print(String(describing: optionalString))
/*
prints:
Optional("{\n\"firstName\" : \"John\",\n\"lastName\" : \"Doe\"\n}")
*/