imagePickerController didFinishPickingMediaWithInfo用法

Question

func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
    if let image = (info[UIImagePickerControllerOriginalImage] as? UIImage) {
        self.memeImage.image = image
    }
    dismiss(animated: true, completion: nil)
}

info是一个包含两个值的字典。但在：

info[UIImagePickerControllerOriginalImage] as? UIImage

其中只有一个字符串值UIImagePickerControllerOriginalImage。

为什么呢？以及如何使用它？

Answer 1

info[UIImagePickerControllerOriginalImage] as? UIImage

info是字典，这是一个集合，其元素是键值对。

此处为字符串类型键： - UIImagePickerControllerOriginalImage

值为： - UIImage对象

此外，您可以在此处看到所有密钥： https://developer.apple.com/documentation/uikit/uiimagepickercontrollerdelegate/editing_information_keys