关于swift：将图像保存到.documentsDirectory，并作为字符串存储在本地Realm中

Saving image to .documentsDirectory, and as a String to store path in local Realm

我正在尝试保存(解析？)图像到我的领域的路径。为此，我尝试将图像另存为jpegData到documentDirectory。

我要保存的图像不需要保存到用户照片库中，只需在应用程序本身中引用和显示即可。

首先，我不确定是否要采取正确的方法。请向我介绍最适合在本地保存图像的解决方案。

我只看到了几个网站，Stack Overflow问题以及几乎没有任何视频，所以有些事情告诉我，有一种更有效的方法可以完成此任务。
将选择的图像保存到CoreData，
如何将映像放入Realm数据库中？以及如何使用writeToFile将图像保存在文档目录中？使我尝试将图像保存到目录中，尤其是最后的SO Question。

我有以下代码，但收到错误"Value of type 'MyViewControllerName' has no member jpegData"关于如何解决此错误或修改代码以保存图像的任何想法？

从照片库或照相机中选择后，我要保存的图像位于selectedImageView中。

我将self.jpegData更改为UIImage.jpegData，selectedImageView.jpegData和UIImageView.jpegData，以获取错误主机，包括Instance member 'jpegData' cannot be used on type 'UIImage'; did you mean to use a value of this type instead?。

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@objc func saveTapped(_ sender: UIBarButtonItem) {
self.performSegue(withIdentifier:"saveTappedSegue", sender: self)
}

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier =="saveTappedSegue" {
let dest = segue.destination as! MyViewControllerName

let documentsDirectory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first!
let fileName ="Image.jpg"
let fileURL = documentsDirectory.appendingPathComponent(fileName)
if let data = self.jpegData(compressionQuality: 1.0), //Error here
!FileManager.default.fileExists(atPath: fileURL.path) {
do {
try data?.write(to: fileURL!)
print("Image Saved")
} catch {
print("error saving file:", error)
}
}

// Remaining code includes writing strings to realm not yet linked to the image.Path. This will be attempted once I can solve this error.

}
}

更新-添加了更多代码

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public var imagePickerController: UIImagePickerController?

public var defaultImageUrl: URL?

internal var selectedImage: UIImage? {
get {
return self.selectedImageView.image
}

set {
switch newValue {
case nil:
self.selectedImageView.image = nil
self.selectImageButton.isEnabled = true
self.selectImageButton.alpha = 1

self.removeImageButton.isEnabled = false
self.removeImageButton.alpha = 0
default:
self.selectedImageView.image = newValue
self.selectImageButton.isEnabled = false
self.selectImageButton.alpha = 0

self.removeImageButton.isEnabled = true
self.removeImageButton.alpha = 1
}
}
}

和

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//image input codes
@IBOutlet weak var selectedImageContainer: UIView!
@IBOutlet weak var selectedImageView: UIImageView!
@IBOutlet weak var selectImageButton: UIButton! {
didSet {
guard let button = self.selectImageButton else { return }
button.isEnabled = true
button.alpha = 1
}
}

@IBOutlet weak var removeImageButton: UIButton! {
didSet {
guard let button = self.removeImageButton else { return }
button.isEnabled = false
button.alpha = 0
}
}

viewDidLoad

中的相关信息

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override func viewDidLoad() {
self.selectedImageView.contentMode = .scaleAspectFit
self.selectImageButton.isEnabled = self.selectedImage == nil
self.selectImageButton.alpha = 1

保存图像

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//MARK: -"Select to Add Photo"
@IBAction func selectImageButton(_ sender: Any) {

if self.imagePickerController != nil {
self.imagePickerController?.delegate = nil
self.imagePickerController = nil
}
self.imagePickerController = UIImagePickerController.init()

let alert = UIAlertController.init(title:"Select Source Type", message: nil, preferredStyle: .actionSheet)

if UIImagePickerController.isSourceTypeAvailable(.camera) {
alert.addAction(UIAlertAction.init(title:"Camera", style: .default, handler: { (_) in
self.presentImagePicker(controller: self.imagePickerController!, source: .camera)
}))
}

if UIImagePickerController.isSourceTypeAvailable(.photoLibrary) {
alert.addAction(UIAlertAction.init(title:"Photo Library", style: .default, handler: { (_) in
self.presentImagePicker(controller: self.imagePickerController!, source: .photoLibrary)
}))
}
alert.addAction(UIAlertAction.init(title:"Cancel", style: .cancel))
self.present(alert, animated: true)
}

internal func presentImagePicker(controller: UIImagePickerController , source: UIImagePickerController.SourceType) {
controller.delegate = self
controller.sourceType = source
controller.allowsEditing = true
self.present (controller, animated: true)
}

@IBAction func removeImageButtonAction(_ sender: UIButton) {
self.selectedImage = nil
}

在我的扩展程序中，我有

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extension AddNewMealVC: UIImagePickerControllerDelegate, UINavigationControllerDelegate {

func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) {

if let image = info[.editedImage] as? UIImage {
self.selectedImageView.image = image
} else if let image = info[.originalImage] as? UIImage {
self.selectedImageView.image = image
}
picker.dismiss(animated: true) {
picker.delegate = nil
self.imagePickerController = nil
}
}

func imagePickerControllerDidCancel(_ picker: UIImagePickerController) {
picker.dismiss(animated: true) {
picker.delegate = nil
self.imagePickerController = nil
}
}
}