swift -> UIImage is stored locally (html read) / album / clipboard

 ----- Stored in APP's directory Documents ------

 

        let urlStr = NSURL(string: "http://images.macx.cn/forum/201301/18/061737r4zfhs4bsrkrnrsq.jpg")
        let data = NSData(contentsOf: urlStr! as URL)
        //if there is no image
        if(data == nil){
            print("no img")
            return;
        }
        let image = UIImage(data: data! as Data)
        //The folder path and image name to be written
        let dt:String = NSHomeDirectory().appending("/Documents/").appending("2.png") as String;
        /*Print path: You can enter the following folder through the finder and then the shortcut key ctrl+shift+g to go to the folder function
         /Users/admin/Library/Developer/CoreSimulator/Devices/8C4DA6F7-4431-402A-92A9-E83087F5159D/data/Containers/Data/Application/4935114D-926D-4EDA-918D-FA14EE023A34/Documents/2.png
        */
        //Write the Image file to the above folder
        try? UIImagePNGRepresentation(image!)?.write(to: URL(fileURLWithPath: dt))
        
        
        // read the pictures in the folder
        let img2 = UIImage(contentsOfFile: dt)
        //If no local image is found
        if(img2 == nil){
            print("not find local img")
            return;
        }
        let imageView = UIImageView(image: img2)
        imageView.contentMode = .center
        imageView.frame = CGRect(x: 0, y: 0, width: 400, height: 200);
        imageView.backgroundColor = UIColor.blue
        self.view.addSubview(imageView)
        

 

The local HTML reads the image stored above 

//Get the path of Documents in this machine
let docu:String = NSSearchPathForDirectoriesInDomains(FileManager.SearchPathDirectory.documentDirectory, FileManager.SearchPathDomainMask.userDomainMask, true)[0];       

//Inject JS into HTML to change the src of the image
wkwebview.evaluateJavaScript("document.getElementById('ffee').setAttribute('src','file://"+docu+"/3g.163.com_big.png');");

 

 

---------Save in photo album-------

Add permissions in info.plist

Privacy - Photo Library Usage Description 

 

 

        let image = UIImage(data: data! as Data)
        UIImageWriteToSavedPhotosAlbum(image!, nil, nil, nil)

 

 --------- Save to clipboard ---------

        let image = UIImage(data: data! as Data)
        UIPasteboard.general.image = image