Convert UIImage to NSData and convert back to UIImage in Swift?

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一向
一向 2020-12-02 07:33

I\'m trying to save a UIImage to NSData and then read the NSData back to a new UIImage in Swift. To convert the UII

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  •  渐次进展
    2020-12-02 08:03

    For safe execution of code, use if-let block with Data to prevent app crash & , as function UIImagePNGRepresentation returns an optional value.

    if let img = UIImage(named: "TestImage.png") {
        if let data:Data = UIImagePNGRepresentation(img) {
           // Handle operations with data here...         
        }
    }
    

    Note: Data is Swift 3+ class. Use Data instead of NSData with Swift 3+

    Generic image operations (like png & jpg both):

    if let img = UIImage(named: "TestImage.png") {  //UIImage(named: "TestImage.jpg")
            if let data:Data = UIImagePNGRepresentation(img) {
                   handleOperationWithData(data: data)     
            } else if let data:Data = UIImageJPEGRepresentation(img, 1.0) {
                   handleOperationWithData(data: data)     
            }
    }
    
    *******
    func handleOperationWithData(data: Data) {
         // Handle operations with data here...
         if let image = UIImage(data: data) {
            // Use image...
         }
    }
    

    By using extension:

    extension UIImage {
    
        var pngRepresentationData: Data? {
            return UIImagePNGRepresentation(self)
        }
    
        var jpegRepresentationData: Data? {
            return UIImageJPEGRepresentation(self, 1.0)
        }
    }
    
    *******
    if let img = UIImage(named: "TestImage.png") {  //UIImage(named: "TestImage.jpg")
          if let data = img.pngRepresentationData {
                  handleOperationWithData(data: data)     
          } else if let data = img.jpegRepresentationData {
                  handleOperationWithData(data: data)     
         }
    }
    
    *******
    func handleOperationWithData(data: Data) {
         // Handle operations with data here...
         if let image = UIImage(data: data) {
            // Use image...
         }
    }
    

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