NSImage to NSData as PNG Swift

问题:

I am writing a Mac app based on an iOS app. The code below converts a UIImage to NSData to upload to Parse.com.

I would like to do the same for Mac but I do not seem to be able to convert it to NSData. What should I be doing?

Thanks

var image = UIImage(named: "SmudgeInc")

let imageData = UIImagePNGRepresentation(image)

let imageFile = PFFile(name:"image.png", data:imageData)

回答1:

You can use the NSImage property TIFFRepresentation to convert your NSImage to NSData:

let myImageData = yourImage.TIFFRepresentation!

If you need to save your image data to a PNG file you can use NSBitmapImageRep(data:) and representationUsingType to create an extension to help you convert Data to PNG format:

Update: Xcode 8.2.1 • Swift 3.0.2

extension NSBitmapImageRep {
    var png: Data? {
        return representation(using: .png, properties: [:])
    }
}
extension Data {
    var bitmap: NSBitmapImageRep? {
        return NSBitmapImageRep(data: self)
    }
}
extension NSImage {
    var png: Data? {
        return tiffRepresentation?.bitmap?.png
    }
    func savePNG(to url: URL) -> Bool {
        do {
            try png?.write(to: url)
            return true
        } catch {
            print(error)
            return false
        }

    }
}

---

usage

let picture  = NSImage(contentsOf: URL(string: "https://i.stack.imgur.com/Xs4RX.jpg")!)!

let imageURL = FileManager.default.urls(for: .desktopDirectory, in: .userDomainMask).first!.appendingPathComponent("image.png")
if picture.savePNG(to: imageURL) {
    print("image saved as PNG")
}