前言：我现在做的项目中服务器返回的图片格式是图片字节数组，需要把字节数组转换成data然后用imageView展示出来。真是服了服务器工程师了！！！折腾半天终于找到答案，记录下来。

Question

In a WebService JSON response is coming. In the response, there is image is coming as a byte array. I have to show the image in a UIImageView. I am trying to convert the byte array to NSData. But not getting how to do that. Any help would be appreciated. I am confident that the byte array has image data in it. Sample Byte array for your reference:

Thanks

I would recommend not to add such lengthy coding which is not needed in your question ... — IronManGill, Aug 8 ‘12 at 8:45
This is not JSON. Or are these squared brackets instead of parnetheses? — user529758, Aug 8 ‘12 at 8:45
@H2CO3 I think that is an NSLog() output. And NSLog() prints NSArrays with () and not []. — HAS, May 25 ‘13 at 5:53

score 18 · Accepted Answer · 2013-08-21 10:27:59Z

You have to convert the JSON to an array of strings first; you can, for example, use the NSJSONSerialization class:

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

Then walk the strings array, convert each entry to an integer, and add it to an allocated byte pointer/array:

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;
}

Then finally make an NSData out of the bytes, then init an UIImage object using it:

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

Note that you are getting NSNumber objects not NSStrings from JSON like that. But since both respond to the intValue message your code still works. Would be better to write NSNumber or maybe even id though. — Sven, May 25 ‘13 at 8:35
what is theJSONString? the method takes nsdata and not nsstring.. how come this works? — Enkidu, Sep 23 ‘14 at 14:19

Paresh Navadiya · Answer 2 · 2012-08-08 08:50:10Z

Here is an example of getting your data into a NSData object.

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

this answers only the very last part of the question. – user529758 Aug 8 ‘12 at 8:53 — user529758, Aug 8 ‘12 at 8:53

Nate Potter · Answer 3 · 2014-09-25 03:55:17Z

and here‘s how to do it in 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);

Mihael Isaev · Answer 4 · 2014-11-30 19:58:03Z

I have my way to do it in 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)
}

Byte Array to NSData——iOS将服务器返回的图片字节数组用UIImageView显示该图像

前言：我现在做的项目中服务器返回的图片格式是图片字节数组，需要把字节数组转换成data然后用imageView展示出来。真是服了服务器工程师了！！！折腾半天终于找到答案，记录下来。

Byte Array to NSData

4 Answers

Byte Array to NSData——iOS将服务器返回的图片字节数组用UIImageView显示该图像

前言：我现在做的项目中 服务器返回的图片格式是 图片字节数组，需要把字节数组转换成data然后用imageView展示出来。真是服了服务器工程师了！！！折腾半天终于找到答案，记录下来。

Byte Array to NSData

4 Answers

前言：我现在做的项目中服务器返回的图片格式是图片字节数组，需要把字节数组转换成data然后用imageView展示出来。真是服了服务器工程师了！！！折腾半天终于找到答案，记录下来。