How Can I convert byte array to String in Swift - arrays

Question

I have a json as below. I need to convert the image to a byte array and post it as a String.
I can convert the image to byte array but how can I convert it to String?
I am getting an error while converting byte array to String.
Error:
"not a valid UTF-8 sequence"
JSON:
"photo1": "[255,216,255,224,0,16,74,70,73, ..... ,]"
Image Data to Byte Array:
func getArrayOfBytesFromImage(imageData:NSData) -> Array<UInt8> {
// the number of elements:
let count = imageData.length / MemoryLayout<Int8>.size
// create array of appropriate length:
var bytes = [UInt8](repeating: 0, count: count)
// copy bytes into array
imageData.getBytes(&bytes, length:count * MemoryLayout<Int8>.size)
var byteArray:Array = Array<UInt8>()
for i in 0 ..< count {
byteArray.append(bytes[i])
}
return byteArray
}
Using getArrayOfBytesFromImage Function:
if let string = String(bytes: getArrayOfBytesFromImage(imageData: imageData), encoding: .utf8) {
print(string)
} else {
print("not a valid UTF-8 sequence")
}

Answer 1

Those are not UTF-8 bytes, so don't say encoding: .utf8. Those bytes do not form a string, so you should not use String.init(bytes:encoding:). You should get the value of those bytes, and get their description one way or another (e.g. by string interpolation).
You don't even need a byte array here. Just go straight to strings, since that's what you're after.
let imageData = Data([1, 2, 3, 4, 5]) // for example
let string = "[\(imageData.map { "\($0)" }.joined(separator: ","))]"
print(string) // prints [1,2,3,4,5]