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.
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];
The goal is to pull a image stored as a varbinary in a sql server through a web service that sends a sqlbinary as a JSON to an iphone. I'm having trouble setting the UIImage from the base64binary sent from the JSON. I'm able to convert the binary to NSData but the image is not being set through the data.
for (int i = 0; i < array.count; i++) {
NSDictionary *mealInfo = [array objectAtIndex:i];
Meal *meal =[[Meal alloc]initWithRestaurant:[mealInfo objectForKey:#"restaurantname"]
mealName:[mealInfo objectForKey:#"itemname"]
description:[mealInfo objectForKey:#"itemdescription"]
Time:[mealInfo objectForKey:#"mealTime"]
price:[mealInfo objectForKey:#"itemprice"]];
//NSString *str = #"data:image/jpg;base64,";
//str = [str stringByAppendingString:[mealInfo objectForKey:#"itemImage"]];
//NSData *imageData = [NSData dataWithContentsOfURL:[NSURL URLWithString:str]];
NSString *str = [mealInfo objectForKey:#"itemImage"];
NSLog(#"%#", str);
NSData *d = [[NSData alloc]initWithData:[NSData dataFromBase64String:str]];
UIImage *image = [UIImage imageWithData:d];
[meal setMealImage:image];
[meals addObject:meal];
}
NSLog(#"%#",[[meals objectAtIndex:0]mealPrice]);
NSLog(#"This is how many meals %d", meals.count);
Assuming the string containing the base 64 encoded is good, your code looks OK. I would look at the dataFromBase64String method to see if that is causing the problem. Here is a version I use based on some else's work:
-(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;
}
You could add a NSData category with this method to make its use very convenient.
I am working on my first iPhone application, in that application I have to calculate the length of NSString, I have tried the available methods and solutions here on SO but for the length is always wrong. For example for a string "test4" NSString.length returns 12 while it should return 5.
I have tried NSString's length property and lengthOfBytesUsingEncoding but both return the same result.
Any help would be appreciated.
EDIT
NSString *string = #"test4";
[string lengthOfBytesUsingEncoding:NSUTF8StringEncoding]; // returns 12
string.length; // returns 12
Complete Code
+(NSString *)AES256Encrypt:(NSString *)data withKey:(NSString *)rawkey{
rawkey = [NSString stringWithFormat:#"%#%#", #"123456789023456", rawkey];
rawkey = [rawkey substringWithRange:NSMakeRange(0, 32)];
NSData *key = [rawkey dataUsingEncoding:NSUTF8StringEncoding];
NSData *iv = [key subdataWithRange:NSMakeRange(0, 16)];
const char *bytes = [data cStringUsingEncoding:NSUTF8StringEncoding];
NSLog(#"%d", data.length); // prints 12
data = [self encode:bytes length:data.length];
NSData *rawData = [data dataUsingEncoding:NSUTF8StringEncoding];
CCCryptorStatus status = kCCSuccess;
NSData *encrypted = [rawData dataEncryptedUsingAlgorithm:kCCAlgorithmAES128 key:key initializationVector:iv options:kCCOptionPKCS7Padding error:&status];
NSString *text = [encrypted base64EncodedString];
return text;
}
Thanks
NSString *myString = #"test4";
int i =myString.length;
NSLog(#"Count =%d",i);
which print Count = 5
I'm using the NSData+compression.h and the Base64Transcoder.h elements to be able to zip and unzip content.
Basically to unzip the server responses.
The unzip method works perfectly
+ (NSString *) unzip: (NSString*) stringValue{
Byte inputData[[stringValue lengthOfBytesUsingEncoding:NSUTF8StringEncoding]];
[[stringValue dataUsingEncoding:NSUTF8StringEncoding] getBytes:inputData];
size_t inputDataSize = (size_t)[stringValue length];
size_t outputDataSize = EstimateBas64DecodedDataSize(inputDataSize);
Byte outputData[outputDataSize];//prepare a Byte[] for the decoded data
Base64DecodeData(inputData, inputDataSize, outputData, &outputDataSize);
NSData *theData = [[NSData alloc] initWithBytes:outputData length:outputDataSize];
//And now we gunzip:
NSData* result = [theData gzipInflate];//make bigger==gunzip
NSString *temp = [[NSString alloc] initWithData:result encoding:NSUTF8StringEncoding];
return temp;
}
But when I try to zip a content, using the simetric way, the gzipDeflate fails, and return an empty or nil value.
This is my zip code
+ (NSData *) zip:(NSData *) theSourceData {
// And now we zip:
NSData *result = [theSourceData gzipDeflate];
Byte inputData[[result length]];
[result getBytes:inputData];
size_t inputDataSize = (size_t)[result length];
size_t outputDataSize = EstimateBas64DecodedDataSize(inputDataSize);
char outputData[outputDataSize];//prepare a Byte[] for the decoded data
Base64EncodeData(inputData, inputDataSize, outputData, &outputDataSize, NO);
NSData *theData = [[NSData alloc] initWithBytes:outputData length:outputDataSize];
return theData;
}
Any suggestions?
Thanks
The problem was on the Base64 encoder.
+ (NSString *) zip:(NSData *) theSourceData {
// And now we zip:
NSData *result = [theSourceData gzipDeflate];
NSString *source = [NSString base64StringFromData:result length:[result length]];
return source;
}
We've integrated the base64StringFromData:length: method to solve it.
Thanks,
Ivan
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].