fetch on retriev of data code example

Example 1: fetch request core data

override func viewWillAppear(_ animated: Bool) {
        if let context = (UIApplication.shared.delegate as? AppDelegate)?.persistentContainer.viewContext {
            if let coreDataToDoItems = try? context.fetch(ToDoItem.fetchRequest()) as? [ToDoItem] {
                toDo = coreDataToDoItems
            }
    }
}

Example 2: fetch get data js

var myHeaders = new Headers();

var myInit = { method: 'GET',
               headers: myHeaders,
               mode: 'cors',
               cache: 'default' };

fetch('flowers.jpg',myInit)
.then(function(response) {
  return response.blob();
})
.then(function(myBlob) {
  var objectURL = URL.createObjectURL(myBlob);
  myImage.src = objectURL;
});