Tutorial by Examples: nd

Writing a view to create object can be quite boring. You have to display a form, you have to validate it, you have to save the item or return the form with an error. Unless you use one of the generic editing views. app/views.py from django.core.urlresolvers import reverse_lazy from django.views.g...

In order to create a random user password we can use the symbols provided in the string module. Specifically punctuation for punctuation symbols, ascii_letters for letters and digits for digits: from string import punctuation, ascii_letters, digits We can then combine all these symbols in a name...

<script> $( ".inclas").datepicker({ minDate: new Date(2007, 1 - 1, 1) maxDate: new Date(2008, 1 - 1, 1) }); </script> <input type ="text" id="datepick" class="inclas">

The background-position property is used to specify the starting position for a background image or gradient .myClass { background-image: url('path/to/image.jpg'); background-position: 50% 50%; } The position is set using an X and Y co-ordinate and be set using any of the units used withi...

A Lens' s a means that you can always find an a within any s. A Prism' s a means that you can sometimes find that s actually just is a but sometimes it's something else. To be more clear, we have _1 :: Lens' (a, b) a because any tuple always has a first element. We have _Just :: Prism' (Maybe a) a...

Here is a simple model that we will use to run a few test queries: class MyModel(models.Model): name = models.CharField(max_length=10) model_num = models.IntegerField() flag = models.NullBooleanField(default=False) Get a single model object where the id/pk is 4: (If there are no...

Context processor to determine the template based on group membership(or any query/logic). This allows our public/regular users to get one template and our special group to get a different one. myapp/context_processors.py def template_selection(request): site_template = 'template_public.html...

Create a new playground file: First option: From Xcode welcome screen, select the first option (Get started with a playground). Second option: From menu select File → New → Playground (⌥⇧⌘N). Name your playground and select the platform (iOS/macOS/tvOS), then click Next. ...

Using Playground it is easy to see that happens inside loops or objects while the change is happening. For example, in the code below, the value of x will change from 1 to 4. import UIKit for x in [1, 2, 3, 4] { x } (1) Clicking on the eye symbol on the right will give us a quick look. (2...

What’s a component? A component is basically a directive that uses a simpler configuration and that is suitable for a component-based architecture, which is what Angular 2 is all about. Think of a component as a widget: A piece of HTML code that you can reuse in several different places in y...

function themeSlug_enqueue_scripts() { wp_enqueue_style( 'themeSlug-reset', get_template_directory_uri() .'/css/reset.css', '1.0.0' ); wp_enqueue_style( 'themeSlug-style', get_template_directory_uri() .'/style.css', 'themeSlug-reset', '1.0.0'); } add_action('wp_enqueue_scripts', 'themeSl...

function output = mymult(a, b) % MYMULT Multiply two numbers. % output = MYMULT(a, b) multiplies a and b. % % See also fft, foo, sin. % % For more information, see <a href="matlab:web('https://google.com')">Google</a>. output = a * b; end help mymult then p...

The padding property sets the padding space on all sides of an element. The padding area is the space between the content of the element and its border. Negative values are not allowed. To save adding padding to each side individually (using padding-top, padding-left etc) can you write it as a shor...

Implementations in classes, including abstract declarations, take precedence over all interface defaults. Abstract class method takes precedence over Interface Default Method. public interface Swim { default void backStroke() { System.out.println("Swim.backStroke"); ...

Macro expansion is the process of turning macros into actual code. This usually happens as part of the compilation process. The compiler will expand all macro forms before actually compiling code. Macro expansion also happens during interpretation of Lisp code. One can call MACROEXPAND manually to ...

json.Unmarshal from the package "encoding/json" decodes a JSON value into the value pointed by the given variable. The parameters are the value to decode in []bytes and a variable to use as a storage for the de-serialized value. The returned value is an error (on failure). encodedValue :...

Given some default routing such as {controller=Home}/{action=Index}/{id?} if you had the url https://stackoverflow.com/questions/1558902 This would go to the QuestionsController and the value 1558902 would be mapped to an id parameter of an index action, i.e. public ActionResult Index(int? id){ ...

To extend on the route binding say you had a url like https://stackoverflow.com/questions/1558902?sort=desc and routing like {controller=Home}/{action=Index}/{id?} public ActionResult Index(int? id, string sort){ //sort would bind to the value in the query string, i.e. "desc" } ...

Often you'd be working with viewmodel classes in asp.net-mvc and would want to bind to properties on these. This works similar to mapping to individual parameters. Say you had a simple view model call PostViewModel like this public class PostViewModel{ public int Id {get;set;} public int Sn...

These are form values that go in the HTTP request using the POST method. (including jQuery POST requests). Say you did an ajax post like $.ajax({ type: 'POST', url: window.updatePost, data: { id: 21, title: 'snappy title' }, //kept short for clarity }); Here the two values...