Tablica bajtów do NSData

Question

W usłudze WebService nadchodzi odpowiedź JSON. W odpowiedzi pojawia się obraz jako tablica bajtów. Muszę pokazać obraz w UIImageView. Próbuję przekonwertować tablicę bajtów na NSData. Ale nie rozumiem, jak to zrobić. Każda pomoc będzie doceniona. Jestem przekonany, że tablica bajtowa zawiera dane obrazu. Próbka Byte tablicy dla odniesienia:

 (137, 
     80, 
     78, 
     71, 
     ... 
     66, 
     96, 
     130) 

Dzięki

Answer 1

Najpierw należy przekonwertować JSON na tablicę łańcuchów; można na przykład użyć NSJSONSerialization class:

NSArray *strings = [NSJSONSerialization JSONObjectWithData:theJSONString options:kNilOptions error:NULL]; 

Następnie pieszo tablicę ciągów, konwertować każdy wpis do liczby całkowitej, a następnie dodaj go do przydzielonego wskaźnik bajt/tablicy:

unsigned c = strings.count; 
uint8_t *bytes = malloc(sizeof(*bytes) * c); 

unsigned i; 
for (i = 0; i < c; i++) 
{ 
    NSString *str = [strings objectAtIndex:i]; 
    int byte = [str intValue]; 
    bytes[i] = byte; 
} 

wreszcie dokonać NSData z bajtów, a następnie init, obiekt UIImage używając go:

NSData *imageData = [NSData dataWithBytesNoCopy:bytes length:c freeWhenDone:YES]; 
UIImage *image = [UIImage imageWithData:imageData]; 

Answer 2

Oto przykład na uzyskanie danych do obiektu NSData.

const unsigned char bytes[] = {values here}; 
NSData *data = [NSData dataWithBytes:bytes length:sizeof(bytes)]; 
NSLog(@"%@", data); 

Answer 3

a oto jak to zrobić w Swift ...

var bytes:[Byte] = [137, 80, 78, 71, 13, 10, 26, 10, 0, 0, 0, 13, 73, 72, 68, 82, 0, 0, 0, 130, 0, 0, 0, 22, 8, 6, 0, 0, 0, 12, 244, 68, 168, 0, 0, 0, 1, 115, 82, 71, 66, 0, 174, 206, 28, 233, 0, 0, 0, 4, 103, 65, 77, 65, 0, 0, 177, 143, 11, 252, 97, 5, 0, 0, 0, 9, 112, 72, 89, 115, 0, 0, 14, 196, 0, 0, 14, 196, 1, 149, 43, 14, 27, 0, 0, 3, 212, 73, 68, 65, 84, 104, 67, 237, 153, 61, 139, 20, 65, 16, 134, 55, 17, 253, 3, 114, 127, 224, 208, 204, 64, 228, 18, 3, 19, 21, 19, 35, 217, 200, 204, 15, 48, 19, 228, 48, 50, 242, 76, 12, 245, 2, 99, 47, 55, 88, 83, 65, 220, 76, 48, 57, 19, 49, 220, 95, 224, 125, 120, 34, 126, 224, 120, 207, 65, 141, 53, 189, 213, 85, 189, 238, 172, 176, 210, 5, 195, 206, 77, 87, 87, 247, 84, 189, 245, 118, 213, 220, 160, 169, 82, 61, 112, 232, 129, 65, 245, 66, 245, 0, 30, 168, 64, 168, 56, 56, 242, 64, 5, 66, 5, 66, 5, 66, 197, 192, 31, 15, 12, 142, 29, 63, 209, 228, 174, 209, 232, 101, 199, 87, 147, 201, 36, 171, 139, 141, 55, 227, 113, 179, 122, 234, 180, 171, 115, 110, 109, 173, 217, 217, 217, 53, 99, 112, 241, 210, 229, 169, 185, 216, 244, 246, 88, 50, 134, 93, 145, 18, 125, 79, 231, 230, 173, 219, 217, 253, 47, 51, 176, 92, 32, 156, 92, 89, 233, 188, 219, 189, 245, 245, 16, 8, 219, 219, 239, 27, 230, 69, 206, 76, 157, 246, 112, 99, 99, 106, 14, 78, 71, 230, 13, 94, 159, 64, 96, 47, 218, 222, 50, 7, 95, 239, 221, 5, 2, 47, 77, 96, 17, 178, 56, 10, 48, 217, 139, 192, 36, 81, 240, 158, 111, 109, 181, 251, 176, 178, 30, 102, 233, 43, 139, 75, 128, 192, 187, 161, 39, 87, 196, 108, 226, 23, 15, 8, 223, 70, 47, 154, 131, 7, 247, 155, 253, 27, 215, 155, 79, 103, 86, 59, 23, 207, 24, 67, 71, 203, 175, 253, 189, 230, 235, 179, 39, 157, 235, 199, 187, 183, 13, 23, 250, 123, 195, 171, 71, 118, 248, 229, 111, 158, 91, 130, 221, 207, 119, 239, 52, 59, 231, 207, 154, 107, 179, 6, 107, 137, 132, 64, 128, 202, 145, 167, 155, 155, 97, 112, 5, 8, 232, 91, 25, 174, 193, 129, 227, 113, 38, 0, 179, 156, 206, 49, 84, 2, 132, 89, 51, 50, 7, 208, 52, 203, 217, 151, 7, 102, 253, 174, 233, 30, 126, 126, 252, 208, 6, 44, 5, 128, 245, 55, 65, 101, 14, 66, 96, 83, 29, 43, 152, 90, 231, 251, 235, 87, 237, 22, 176, 19, 233, 235, 185, 2, 196, 16, 8, 165, 103, 191, 232, 105, 167, 64, 237, 158, 51, 1, 217, 181, 225, 112, 74, 7, 16, 105, 241, 108, 244, 5, 4, 246, 66, 112, 229, 138, 128, 239, 49, 130, 100, 109, 9, 8, 68, 103, 247, 202, 133, 44, 16, 34, 59, 4, 94, 196, 2, 1, 207, 96, 32, 139, 153, 176, 13, 248, 90, 32, 224, 136, 156, 195, 117, 198, 122, 122, 105, 150, 144, 85, 158, 190, 181, 158, 117, 254, 70, 199, 140, 55, 158, 218, 155, 199, 150, 204, 245, 106, 4, 178, 211, 10, 28, 52, 205, 24, 23, 247, 150, 14, 99, 22, 35, 136, 46, 129, 204, 101, 59, 64, 128, 238, 83, 187, 28, 31, 233, 209, 147, 234, 0, 220, 22, 8, 81, 6, 136, 19, 60, 61, 139, 46, 75, 106, 11, 177, 205, 113, 97, 117, 20, 243, 4, 175, 111, 32, 68, 93, 131, 21, 12, 28, 157, 138, 197, 26, 204, 205, 29, 13, 114, 116, 96, 199, 2, 3, 243, 172, 140, 103, 29, 97, 3, 126, 249, 219, 154, 223, 2, 129, 5, 162, 2, 73, 186, 136, 92, 96, 114, 231, 38, 52, 90, 18, 204, 180, 93, 45, 169, 17, 116, 129, 103, 221, 75, 231, 81, 98, 43, 98, 22, 93, 183, 228, 142, 36, 11, 8, 60, 75, 37, 167, 103, 1, 1, 6, 209, 98, 129, 136, 121, 127, 115, 36, 9, 59, 116, 128, 16, 177, 130, 156, 221, 179, 2, 129, 151, 136, 90, 79, 198, 115, 242, 47, 106, 4, 214, 240, 186, 34, 41, 110, 163, 154, 164, 132, 158, 177, 1, 101, 167, 20, 157, 99, 132, 20, 72, 86, 230, 151, 50, 130, 102, 7, 125, 223, 1, 66, 196, 10, 146, 17, 139, 0, 66, 238, 35, 19, 123, 138, 170, 119, 93, 228, 165, 247, 227, 195, 2, 80, 23, 118, 158, 173, 40, 17, 116, 75, 59, 11, 35, 16, 112, 221, 38, 114, 111, 213, 8, 60, 183, 24, 161, 20, 8, 95, 30, 63, 10, 107, 4, 169, 37, 210, 22, 117, 10, 8, 57, 103, 80, 221, 71, 244, 234, 181, 84, 81, 59, 233, 101, 90, 201, 177, 18, 209, 122, 180, 119, 230, 35, 81, 167, 83, 242, 49, 105, 150, 246, 77, 3, 130, 190, 126, 30, 32, 48, 223, 90, 155, 35, 3, 144, 88, 44, 196, 250, 204, 153, 2, 2, 206, 176, 40, 178, 36, 171, 254, 7, 32, 148, 116, 58, 105, 123, 155, 130, 56, 151, 241, 94, 27, 40, 140, 49, 15, 16, 216, 199, 172, 107, 3, 2, 10, 209, 129, 20, 88, 250, 101, 96, 5, 93, 120, 105, 54, 64, 79, 198, 104, 13, 245, 189, 215, 91, 243, 37, 49, 87, 216, 201, 71, 171, 28, 43, 48, 47, 93, 43, 183, 7, 235, 185, 174, 63, 188, 226, 82, 214, 231, 61, 162, 34, 52, 250, 178, 136, 115, 115, 25, 168, 1, 129, 142, 238, 8, 184, 151, 234, 94, 126, 211, 175, 143, 100, 183, 238, 6, 244, 7, 41, 222, 1, 102, 64, 199, 99, 38, 198, 244, 145, 83, 255, 13, 29, 85, 127, 61, 140, 19, 92, 249, 76, 44, 191, 58, 248, 61, 44, 225, 154, 72, 215, 182, 148, 43, 16, 22, 29, 133, 37, 177, 95, 129, 176, 36, 129, 90, 244, 54, 43, 16, 22, 237, 225, 37, 177, 255, 27, 38, 183, 224, 140, 178, 26, 189, 95, 0, 0, 0, 0, 73, 69, 78, 68, 174, 66, 96, 130]; 

var imageData:NSData = NSData(bytes: bytes, length: bytes.count); 
var image:UIImage = UIImage(data: imageData); 
var imageView:UIImageView = UIImageView(image: image); 

Answer 4

mam sposób to zrobić w Swift

if let serverBytesArray = serverAnswer as? NSArray { 
    var bytes:[Byte] = [] 
    for serverByte in serverBytesArray { 
     bytes.append(Byte(serverByte as UInt)) 
    } 
    var data = NSData(bytes: bytes, length: bytes.count); 
    let tmpDir = NSTemporaryDirectory() 
    data.writeToFile(tmpDir.stringByAppendingPathComponent("test.pdf"), atomically: true) 
}