Save UIImage to UserDefault as Array , Swift

Question

I have one UiTableView , I need to have one Array Data Saving UIimage for Temporary time .

I Think if I use UserDefault it's not bad solution but I don't know how save in UserDefault I know I don't use .stringArray I don't know how can I Save Image in Array Default

struct Constants {

    static let myKeyImage = "myKeyIMG”

}


 var arrayiMG = [String]()
  self.defaults.stringArray(forKey: Constants.myKeyImage)


if (self.defaults.stringArray(forKey: Constants.myKeyImage) != nil)
{
arrayUrl = self.defaults.stringArray(forKey: Constants.myKeyURL)!
}

I want to save in .png or jpg Like this

func plane(from anchor: ARPlaneAnchor) -> SCNNode {
    if (`extension`.lowercased() == "png") {
        data = UIImagePNGRepresentation(image)
    }
    else if (`extension`.lowercased() == "jpg") {
        data = .uiImageJPEGRepresentation()
    }

}

@Vyacheslav if it's possible please give me one good way and one good array data — Miloo, Feb 11 '18 at 21:43
*"I Think if I use UserDefault it's not bad solution"* - it is a bad solution. UserDefaults is not meant to store lots data. — rmaddy, Feb 11 '18 at 22:41
@rmaddy I need to save for Temporary time and after I need to delete the image array do you have better solutions ? — Miloo, Feb 11 '18 at 23:37
As @Jake stated at the end of his answer, write the images to files. — rmaddy, Feb 11 '18 at 23:53
@Miloo If it is temporary just save them at a temporary location. https://stackoverflow.com/questions/11897825/ios-temporary-folder-location/39318537?s=1|42.0586#39318537 . Btw what do you mean by temporary? Temporary files should just persist long enough for you to execute a method/function. Another option would be using the caches folder or NSCache to store it in memory. I suggest you to take a look at Apple File System Basics documentation https://developer.apple.com/library/content/documentation/FileManagement/Conceptual/FileSystemProgrammingGuide/FileSystemOverview/FileSystemOverview.html — Leo Dabus, Feb 12 '18 at 01:39
@LeoDabus I can't find one example for NSCache swift in stack overflow if you can give me one sample code or for my question do you have answer thanks — Miloo, Feb 12 '18 at 09:01

Jake · Accepted Answer · 2018-02-11T22:11:12.660

Something like this would work:

extension UserDefaults {
    func imageArray(forKey key: String) -> [UIImage]? {
        guard let array = self.array(forKey: key) as? [Data] else {
            return nil
        }
        return array.flatMap() { UIImage(data: $0) }
    }

    func set(_ imageArray: [UIImage], forKey key: String) {
        self.set(imageArray.flatMap({ UIImagePNGRepresentation($0) }), forKey: key)
    }
}

Usage:

let imageArray = [image1, image2, image3]
UserDefaults.standard.set(imageArray, forKey: "images")

let images = UserDefaults.standard.imageArray(forKey: "image")

However, I wouldn't recommend storing an array of images in UserDefaults. Storing the images as files would probably be more appropriate. You could then store their paths in UserDefaults.

Save UIImage to UserDefault as Array , Swift

1 Answers1