I currently have an NSString containing hex values. I need to convert this NSString object into an NSData object, without changing its contents at all.
I use this code to "parse" the debug output of an NSData object (what you get in the console if you just NSLog an NSData object) back into NSData:
-(NSData*) bytesFromHexString:(NSString *)aString;
{
NSString *theString = [[aString componentsSeparatedByCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]] componentsJoinedByString:nil];
NSMutableData* data = [NSMutableData data];
int idx;
for (idx = 0; idx+2 <= theString.length; idx+=2) {
NSRange range = NSMakeRange(idx, 2);
NSString* hexStr = [theString substringWithRange:range];
NSScanner* scanner = [NSScanner scannerWithString:hexStr];
unsigned int intValue;
if ([scanner scanHexInt:&intValue])
[data appendBytes:&intValue length:1];
}
return data;
}
It's not my most robust code, but it does the job of parsing [nsdata_object description].
Related
I have an one hexa decimal number
535443326663315634524877795678586b536854535530342f44526a795744716133353942704359697a6b736e446953677171555473
I want to convert this number to ASCII format which will look like this
STC2fc1V4RHwyVxXkShTSU04/DRjyWDqa359BpCYizksnDiSgqqUTsYUOcHKHNMJOdqR1/TQywpD9a9xhri
i have seen solutions here but none of them is useful to me
NSString containing hex convert to ascii equivalent
i checked here but they give different result. Any help
This works perfectly
- (NSString *)stringFromHexString:(NSString *)hexString {
// The hex codes should all be two characters.
if (([hexString length] % 2) != 0)
return nil;
NSMutableString *string = [NSMutableString string];
for (NSInteger i = 0; i < [hexString length]; i += 2) {
NSString *hex = [hexString substringWithRange:NSMakeRange(i, 2)];
NSInteger decimalValue = 0;
sscanf([hex UTF8String], "%x", &decimalValue);
[string appendFormat:#"%c", decimalValue];
NSLog(#"string--%#",string);
}
_hexString1=string;
NSLog(#"string ---%#",_hexString1);
return string;
}
If you're starting with NSData * you could get the ASCII string this way:
NSData *someData = [NSData dataWithHexString:#"ABC123"];
NSString *asciiString = [[NSString alloc] initWithData: someData encoding:NSASCIIStringEncoding];
I have an int value which I obtained from the character 爸, which is 29240. I can convert this number to hex, but I have no clue how to write the chinese character out in an NSString with only the int 29240.
Basically, what I did was:
NSString * s = #"爸";
int a = [s characterAtIndex:0];
NSLog(#"%d", a);
What it gave as output was 29240.
However, I don't know how to create an NSString that just contains 爸 from only the int 29240.
I converted 29240 into binary which gave me 7238, but I can't seem to create a method which allows me to input any integer and NSLog the corresponding character.
I can hard code it in, so that I have
char cString[] = "\u7238";
NSData *data = [NSData dataWithBytes:cString length:strlen(cString)];
NSString *string = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
NSLog(#"result string: %#", string);
But I'm not sure how to do it with any int.
Thanks to anyone who can help me!
To create a string from one (or more) Unicode characters use initWithCharacters:
unichar c = 29240;
NSString *string = [[NSString alloc] initWithCharacters:&c length:1];
NSString uses UTF-16 characters internally, so
this works for all characters in the "Basic Multilingual Plane", i.e. all characters up to U+FFFF. The following code works for arbitrary characters:
uint32_t ch = 0x1F60E;
ch = OSSwapHostToLittleInt32(ch); // To make it byte-order safe
NSString *s1 = [[NSString alloc] initWithBytes:&ch length:4 encoding:NSUTF32LittleEndianStringEncoding];
NSLog(#"%#", s1);
// Output: 😎
Try out this code snippet to get you started in the right direction:
NSString *s = #"0123456789";
for (int i = 0; i < [s length]; i++) {
NSLog(#"Value: %d", [s characterAtIndex:i]);
}
Just pass in the character as an integer:
unichar decimal = 12298;
NSString *charStr = [NSString stringWithFormat:#"%C", decimal];
I am making a turn-based game where I have stored an integer variable 'points' into NSData, which is then stored by gamecenter. So far I am doing this as follows:
NSString *newString=[[NSString alloc] initWithFormat: #"%i", points];
NSData *data = [newString dataUsingEncoding:NSUTF8StringEncoding];
I need to store more variables into NSData *data. How can i do this?
I am now aware that you can store 2 integers in the string *newString by:
NSString *newString=[[NSString alloc] initWithFormat: #"%i, %i", points, otherInteger];
However I don't know how I would decode this as the string would be stored as one integer value following on from the last. It might not be the best implementation anyway so any suggestions would be appreciated.
You could do something like this:
// for encoding
int32_t points = ...;
int32_t otherInteger = ...;
NSMutableData *data = [NSMutableData data];
[data appendBytes:&points length:sizeof(int32_t)];
[data appendBytes:&otherInteger length:sizeof(int32_t)];
.
.
.
// for decoding
NSData *data = ...;
int32_t points;
int32_t otherInteger;
int index = 0;
NSRange range;
range = NSMakeRange(index, sizeof(int32_t));
[data getBytes:&points range:range];
index += sizeof(int32_t);
range = NSMakeRange(index, sizeof(int32_t));
[data getBytes:&otherInteger range:range];
index += sizeof(int32_t);
.
.
.
NSString *string1 = #"<616263>";
I want to make this into NSData *data1 = <616263>;
so that when I
NSString *string2 = [[NSString alloc] initWithData:data1 encoding:NSUTF8StringEncoding];
NSLog(#"%#", string2);
Result: abc
would come out
p.s.
<616263>, this is data expression of #"abc"
The trick is converting 616263 to abc. Since you are starting with the ASCII representation of the character codes, you need to convert your NSString to an array of bytes (or your original data source to an array instead of saving it as an NSString in the first place).
NSString *string1 = #"616263";
// Make sure that buffer is big enough!
char sourceChars[7];
[string1 getCString:sourceChars maxLength:7 encoding:NSUTF8StringEncoding];
char destBuffer[3];
char charBuffer[3];
// Loop through sourceChars and convert the ASCII character groups to char's
// NOTE: I assume that these are always two character groupings per your example!
for (int index = 0; index < [string1 length]; index = index + 2) {
// Copy the next two digits into charBuffer
strncpy(charBuffer, &sourceChars[index], 2);
charBuffer[2] = '\0';
// convert charBuffer (ie 61) from hex to decimal
destBuffer[index / 2] = strtol(charBuffer, NULL, 16);
}
// destBuffer is properly formatted: init data1 with it.
NSData *data1 = [NSData dataWithBytes:destBuffer length:[string1 length]/2];
// Test
NSString *string2 = [[NSString alloc] initWithData:data1 encoding:NSUTF8StringEncoding];
NSLog(#"%#", string2); // Prints abc
I have some Bytes of image in my string and i want to draw it to UIImageView ...Here is my code
NSString* str= #"<89504e47 0d0a1a0a 0000000d 49484452 ........... 454e44ae 426082>";
NSData* data=[str dataUsingEncoding:NSUTF8StringEncoding];
NSLog(#"My NSDATA %#",data);
imageView.image=[UIImage imageWithData:data];
Now when i saw that printed data on console it is not in same format what i gave to that string..The output is something like.....
<3c383935 30346534 37203064 30613161..........
So my imageview show nothing..... please help
if question was: How to convert string data to image then this is answer.
NSData *imgData = [NSData dataWithContentsOfFile:[[NSBundle mainBundle] pathForResource:#"icon" ofType:#"png"]];
// set your string data into inputString var
NSString *inputString = [imgData description];
NSLog(#"input string %#",inputString);
// clearing string from trashes
NSString *dataStr = [inputString stringByTrimmingCharactersInSet:[NSCharacterSet characterSetWithCharactersInString:#"<>"]];
// separate by words of 4 bytes
NSArray *words = [dataStr componentsSeparatedByString:#" "];
// calculate number of bytes
NSArray *sizes = [words valueForKey:#"length"];
int sizeOfBytes = 0;
for (NSNumber *size in sizes) {
sizeOfBytes += [size intValue]/2;
}
int bytes[sizeOfBytes];
int counts = 0;
for (NSString *word in words) {
// convert each word from string to int
NSMutableString *ostr = [NSMutableString stringWithCapacity:[word length]];
while ([word length] > 0) {
[ostr appendFormat:#"%#", [word substringFromIndex:[word length] - 2]];
word = [word substringToIndex:[word length] - 2];
}
NSScanner *scaner = [NSScanner scannerWithString:ostr];
unsigned int val;
[scaner scanHexInt:&val];
bytes[counts] = val;
counts++;
}
// get NSData form c array
NSData* data = [NSData dataWithBytes:bytes length:sizeOfBytes];
NSLog(#"My NSDATA %#",data);
// your image is ready
UIImage *image = [UIImage imageWithData:data];
NSLog(#"image: %#",image);
what you are seeing in NSLog output are the ASCII codes of the string characters.
for example:
NSString* str = #"A";
NSData* data=[str dataUsingEncoding:NSUTF8StringEncoding];
NSLog(#"%#",data);
you will see something like:
<41....
that's because 0x41 is the code for letter A.
Same is happening with your string.
The data is exactly what you're feeding it: a simple string (printed as raw byte values). But I guess your input string is a hexdump and you manually need to turn into bytes.