Converting NSData to Integer in Swift

Question

In Objective-C the code looked liked this and worked flawlessly,

NSInteger random = arc4random_uniform(99) + 1 
NSData *data = [NSData dataWithBytes:& ra         


        

Answer 1

You might find this method useful if you are doing it a lot:

func readInteger(data : NSData, start : Int) -> T {
    var d : T = 0
    data.getBytes(&d, range: NSRange(location: start, length: sizeof(T)))
    return d
}

The function takes as a parameter the start position in the data to read the numeric type and it returns a value of the a type inferred from whatever you are assigning it to.

For example:

let i : UInt32 = readInteger(data, 10);

reads an 4 byte integer from position 10 in the data.

If you change UInt32 to UInt16 it will read two bytes.