First of all, there is not built in support for traditional abstraction in JavaScript. At least, there are not any types like interfaces and abstract classes. However, interface can be implemented using Object.create method and prototypes. For more information, visit [here][1].


  [1]: http://www.yusufaytas.com/achieving-abstraction-in-javascript/

Quoting from an article written by Mark McDonnell:

&gt; In JavaScript there are no true &quot;classic&quot; Object-Oriented features,
&gt; but through clever usage of the language you can emulate an Interface
&gt; for use with a JavaScript API.

See the following for the complete article:

http://www.javascriptbank.com/how-implement-interfaces-in-javascript.html

How can I run a function in *Python*, at a given time?

For example:

    run_it_at(func, &#39;2012-07-17 15:50:00&#39;)

and it will run the function `func` at 2012-07-17 15:50:00.

I tried the [sched.scheduler][1], but it didn&#39;t start my function.

    import time as time_module
    scheduler = sched.scheduler(time_module.time, time_module.sleep)
    t = time_module.strptime(&#39;2012-07-17 15:50:00&#39;, &#39;%Y-%m-%d %H:%M:%S&#39;)
    t = time_module.mktime(t)
    scheduler_e = scheduler.enterabs(t, 1, self.update, ())

What can I do?


  [1]: http://docs.python.org/library/sched.html#scheduler-objects

Start a Function at Given Time

I&#39;m trying to display a formatted decimal in a TextBox using data binding in WPF.

## Goals ##

Goal 1: When setting a decimal property in code, display 2 decimal places in the TextBox.

Goal 2: When a user interacts with (types in) the TextBox, don&#39;t piss him/her off.

Goal 3: Bindings must update source on PropertyChanged.

## Attempts ##

***Attempt 1: No formatting.***

Here we&#39;re starting nearly from scratch.

    &lt;TextBox Text=&quot;{Binding Path=SomeDecimal, UpdateSourceTrigger=PropertyChanged}&quot; /&gt;

Violates Goal 1. `SomeDecimal = 4.5` will show &quot;4.50000&quot; in the TextBox.

***Attempt 2: Use StringFormat in the Binding.***

    &lt;TextBox Text=&quot;{Binding Path=SomeDecimal, UpdateSourceTrigger=PropertyChanged, StringFormat=F2}&quot; /&gt;

Violates Goal 2.  Say SomeDecimal is 2.5, and the TextBox is displaying &quot;2.50&quot;.  If we select all and type &quot;13.5&quot; we end up with &quot;13.5.00&quot; in the TextBox because the formatter &quot;helpfully&quot; inserts decimals and zeros.

***Attempt 3: use Extended WPF Toolkit&#39;s MaskedTextBox.***

http://wpftoolkit.codeplex.com/wikipage?title=MaskedTextBox

Assuming I&#39;m reading the documentation correctly, the mask ##0.00 means &quot;two optional digits, followed by a required digit, a decimal point, and two more required digits.  This forces me to say &quot;the largest possible number that can go into this TextBox is 999.99&quot; but let&#39;s say I&#39;m ok with that.

    &lt;xctk:MaskedTextBox Value=&quot;{Binding Path=SomeDecimal, UpdateSourceTrigger=PropertyChanged}&quot; Mask=&quot;##0.00&quot; /&gt;

Violates Goal 2.  The TextBox starts with `___.__` and selecting it and typing 5.75 yields `575.__`.  The only way to get 5.75 is to select the TextBox and type `&lt;space&gt;&lt;space&gt;5.75`.

***Attempt 4: use Extended WPF Toolkit&#39;s DecimalUpDown spinner.***

http://wpftoolkit.codeplex.com/wikipage?title=DecimalUpDown

    &lt;xctk:DecimalUpDown Value=&quot;{Binding Path=SomeDecimal, UpdateSourceTrigger=PropertyChanged}&quot; FormatString=&quot;F2&quot; /&gt;

Violates Goal 3.  DecimalUpDown happily ignores UpdateSourceTrigger=PropertyChanged.  One of the Coordinators on the Extended WPF Toolkit Codeplex page suggests a modified ControlTemplate at http://wpftoolkit.codeplex.com/discussions/352551/.  This satisfies Goal 3, but violates Goal 2, exhibiting the same behavior as in Attempt 2.

***Attempt 5: Using style datatriggers, only use formatting if user is not editing.***

https://stackoverflow.com/questions/8183922

Even if this one satisfied all three goals, I wouldn&#39;t want to use it.  (A) Textboxes become 12 lines each instead of 1, and my application contains many, many textboxes.  (B) All my textboxes already have a Style attribute which points to a global StaticResource which sets Margin, Height, and other things.  (C) You may have noticed the code below sets the binding Path twice, which violates the DRY principal.

    &lt;TextBox&gt;
        &lt;TextBox.Style&gt;
            &lt;Style TargetType=&quot;{x:Type TextBox}&quot;&gt;
                &lt;Setter Property=&quot;Text&quot; Value=&quot;{Binding Path=SomeDecimal, StringFormat=F2}&quot; /&gt;
                &lt;Style.Triggers&gt;
                    &lt;Trigger Property=&quot;IsFocused&quot; Value=&quot;True&quot;&gt;
                        &lt;Setter Property=&quot;Text&quot; Value=&quot;{Binding Path=SomeDecimal, UpdateSourceTrigger=PropertyChanged}&quot; /&gt;
                    &lt;/Trigger&gt;
                &lt;/Style.Triggers&gt;
            &lt;/Style&gt;
        &lt;/TextBox.Style&gt;
    &lt;/TextBox&gt;

All these uncomfortable things aside...

Violates Goal 2.  First, clicking on a TextBox which displays &quot;13.50&quot; suddenly makes it display &quot;13.5000&quot;, which is unexpected.  Second, if starting with a blank TextBox, and I type &quot;13.50&quot;, the TextBox will contain &quot;1350&quot;.  I can&#39;t explain why, but pressing the period key doesn&#39;t insert decimals if the cursor is at the right end of the string in the TextBox.  If the TextBox contains a string with length &gt; 0, and I reposition the cursor to anywhere except the right end of the string, I can then insert decimal points.

***Attempt 6: Do it myself.***

I&#39;m about to embark on a jouney of pain and suffering, by either subclassing TextBox, or creating an attached property, and writing the formatting code myself.  It will be full of string manipulation, and cause substantial hairloss.

----------

Does anyone have any suggestions for formatting decimals bound to textboxes that satisfies all the above goals?

How can I format a decimal bound to TextBox without angering my users?


Is it possible to implement interface in javascript

if yes do you have any example ?

How to implement interface in javascript

<p>Is it possible to implement interface in javascript</p>
<p>if yes do you have any example ?</p>


I am pretty new to this whole MV* client-side framework frenzy. It doesn&#39;t have to be AngularJS, but I picked it because it feels more natural to me than either Knockout, Ember or Backbone. Anyway what is the workflow like? Do people start with developing a client-side application in AngularJS and then hooking up the back-end to it?

Or the other way around by first building the back-end in Django, Flask, Rails and then attaching an AngularJS app to it? Is there a &quot;right&quot; way of doing it, or is it just a personal preference in the end?

I am also not sure whether to structure my project according to the Flask or AngularJS? community practices.

For example, Flask&#39;s minitwit app is structured like so:

    minitwit
    |-- minitwit.py
    |-- static
       |-- css, js, images, etc...
    `-- templates
       |-- html files and base layout

AngularJS tutorial app is structured like this:

    angular-phonecat
    |-- app
        `-- css
        `-- img
        `-- js
        `-- lib
        `-- partials
        `-- index.html
    |-- scripts
     `-- node.js server and test server files
    
I could picture a Flask app by itself, and it&#39;s fairly easy to see AngularJS app like ToDo List by itself but when it comes to using both of these technologies I don&#39;t understand how they work together. It almost seems like I don&#39;t need a server-side web-framework when you already have AngularJS, a simple Python web server will suffice. In the AngularJS to-do app for example they use MongoLab to talk to the database using Restful API. There was no need having a web framework on the back-end.

Maybe I am just awfully confused, and AngularJS is nothing more than a fancy jQuery library so I should use just like I would use jQuery in my Flask projects (assuming I change the AngularJS template syntax to something that doesn&#39;t conflict with Jinja2). I hope my questions make some sense. I mainly work on the back-end and this client-side framework is an unknown territory for me.

Typical AngularJS workflow and project structure (with Python Flask)


I&#39;m currently dealing with handlebars.js in an express.js application. To keep things modular, I split all my templates in partials.

**My problem**: I couldn&#39;t find a way to pass variables through an partial invocation. Let&#39;s say I have a partial which looks like this:

    &lt;div id=myPartial&gt;
        &lt;h1&gt;Headline&lt;h1&gt;
        &lt;p&gt;Lorem ipsum&lt;/p&gt;
    &lt;/div&gt;
Let&#39;s assume I registered this partial with the name &#39;myPartial&#39;. In another template I can then say something like:

    &lt;section&gt;
        {{&gt; myPartial}}
    &lt;/section&gt;

This works fine, the partial will be rendered as expected and I&#39;m a happy developer. But what I now need, is a way to pass different variables throught this invocation, to check within a partial for example, if a headline is given or not. Something like:

    &lt;div id=myPartial&gt;
        {{#if headline}}
        &lt;h1&gt;{{headline}}&lt;/h1&gt;
        {{/if}}
        &lt;p&gt;Lorem Ipsum&lt;/p&gt;
    &lt;/div&gt;

And the invokation should look something like this:

    &lt;section&gt;
        {{&gt; myPartial|&#39;headline&#39;:&#39;Headline&#39;}}
    &lt;/section&gt;

or so.

I know, that I&#39;m able to define all the data I need, before I render a template. But I need a way to do it like just explained. Is there a possible way?



Passing variables through handlebars partial

I was wondering which is the minimum and the maximum date allowed for a Javascript `Date` object. I found that the minimum date is something like 200000 B.C., but I couldn&#39;t get any reference about it.

Does anyone know the answer? I just hope that it doesn&#39;t depend on the browser.

An answer in &quot;epoch time&quot; (= milliseconds from 1970-01-01 00:00:00 UTC+00) would be the best.

Minimum and maximum date

I&#39;m making a small web app in which a user enters a server URL from which it pulls a load of data with an AJAX request.

Since the user has to enter the URL manually, people generally forget the trailing slash, even though it&#39;s required (as some data is appended to the url entered). I need a way to check if the slash is present, and if not, add it.

This seems like a problem that jQuery would have a one-liner for, does anyone know how to do this or should I write a JS function for it?

javascript/jquery add trailing slash to url (if not present)

Is defining JavaScript variables inside if-statements correct?

    if(a==1){
        var b = 1;
    } else {
        var b = 0;
    }

I know the code above will work, however, WebMatrix highlights the variables.

Should I define the variables outside the if-statement? Or the first option&#39;s correct? Or it doesn&#39;t really matter?

    var b = &#39;&#39;;
    if(a==1){
        b = 1;
    } else {
        b = 0;
    }

Content Type	Original Author	Original Content on Stackoverflow
Question	user1365697	View Question on Stackoverflow
Solution 1 - Javascript	yusufaytas	View Answer on Stackoverflow
Solution 2 - Javascript	PraveenVenu	View Answer on Stackoverflow

How to implement interface in javascript

Javascript Problem Overview

Javascript Solutions

Solution 1 - Javascript

Solution 2 - Javascript

How can I format a decimal bound to TextBox without angering my users?

Start a Function at Given Time

Attributions