The simplest way would be to directly subtract the date objects from one another.

For example:

    var hours = Math.abs(date1 - date2) / 36e5;

The subtraction returns the difference between the two dates in milliseconds. `36e5` is the scientific notation for `60*60*1000`, dividing by which converts the milliseconds difference into hours.

Try using `getTime` ([mdn doc][1]):

    var diff = Math.abs(date1.getTime() - date2.getTime()) / 3600000;
    if (diff &lt; 18) { /* do something */ }

Using `Math.abs()` we don&#39;t know which date is the smallest. This code is probably more relevant:

    var diff = (date1 - date2) / 3600000;
    if (diff &lt; 18) { array.push(date1); }


  [1]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/getTime

Use the timestamp you get by calling `valueOf` on the date object:    

    var diff = date2.valueOf() - date1.valueOf();
    var diffInHours = diff/1000/60/60; // Convert milliseconds to hours
    

How to convert this timestamp `1382086394000` to `2013-10-18 08:53:14` using a function in javascript? Currently I have this function:

    function cleanDate(d) {return new Date(+d.replace(/\/Date$(\d+)$\//, &#39;$1&#39;));}

Function to convert timestamp to human date in javascript

I&#39;ve used some apps where when I fill my username, then go to my password, if I hit &quot;Done&quot; on the keyboard, the login form is automatically submitted, without me having to click the submit button. How is this done?

Implicit &quot;Submit&quot; after hitting Done on the keyboard at the last EditText

I got two Date objects and I want to calculate the difference in hours.

If the difference in hours is less than 18 hours, I want to push the date object into an array.

Javascript / jQuery, doesn&#39;t really matter; what works the best will do.

How to get the hours difference between two date objects?

I got two Date objects and I want to calculate the difference in hours.
If the difference in hours is less than 18 hours, I want to push the date object into an array.
Javascript / jQuery, doesn't really matter; what works the best will do.

I have a function that runs an AJAX call on the change of an input.

But, there is a chance that the function will be fired again before the previous ajax call has completed.

My question is, how would I abort the previous AJAX call before starting a new one?
Without using a global variable. (See answer to a similar question [here][1])

[JSFiddle][2] of my current code: 

**Javascript:**

    var filterCandidates = function(form){
        //Previous request needs to be aborted.
        var request = $.ajax({
            type: &#39;POST&#39;,
            url: &#39;/echo/json/&#39;,
            data: {
                json: JSON.stringify({
                    count: 1
                })
            },
            success: function(data){
                if(typeof data !== &#39;undefined&#39;){
                    jQuery(&#39;.count&#39;).text(data.count)
                    console.log(data.count);
                }
            }
        });
    };
    
    if(jQuery(&#39;#search&#39;).length &gt; 0){
        var form = jQuery(&#39;#search&#39;);
        jQuery(form).find(&#39;:input&#39;).change(function() {
            filterCandidates(form);
        });
        filterCandidates(form);
    }

**HTML:**

    &lt;form id=&quot;search&quot; name=&quot;search&quot;&gt;
        &lt;input name=&quot;test&quot; type=&quot;text&quot; /&gt;
        &lt;input name=&quot;testtwo&quot; type=&quot;text&quot; /&gt;
    &lt;/form&gt;
    &lt;span class=&quot;count&quot;&gt;&lt;/span&gt;

  [1]: https://stackoverflow.com/questions/4551175/how-to-cancel-abort-jquery-ajax-request
  [2]: https://jsfiddle.net/YzDBg/

Abort new AJAX request before completing the previous one

Is `id` an attribute or property of HTML?

should I do `$(&#39;#selector&#39;).attr(&#39;id&#39;);` or `$(&#39;#selector&#39;).prop(&#39;id&#39;);`

I&#39;ve read many articles and am still confused.

Could someone please explain to me what the differences between attributes &amp; properties in HTML/JS are in very simple language?

HTML - attributes vs properties

I need to search inside a json list of countries. The json is like:

    [ 
    {&quot;name&quot;: &quot;Afghanistan&quot;, &quot;code&quot;: &quot;AF&quot;}, 
    {&quot;name&quot;: &quot;&#197;land Islands&quot;, &quot;code&quot;: &quot;AX&quot;}, 
    {&quot;name&quot;: &quot;Albania&quot;, &quot;code&quot;: &quot;AL&quot;}, 
    {&quot;name&quot;: &quot;Algeria&quot;, &quot;code&quot;: &quot;DZ&quot;}
    ]


I get from database only the code and would output the entire name. So if I get &quot;AL&quot; I would like to retrieve from json &quot;Albania&quot;

Javascript find json value

I&#39;m trying to resize some images with canvas but I&#39;m clueless on how to smoothen them.
On photoshop, browsers etc.. there are a few algorithms they use (e.g. bicubic, bilinear) but I don&#39;t know if these are built into canvas or not.

Here&#39;s my fiddle: http://jsfiddle.net/EWupT/

    var canvas = document.createElement(&#39;canvas&#39;);
    var ctx = canvas.getContext(&#39;2d&#39;);
    canvas.width=300
    canvas.height=234
    ctx.drawImage(img, 0, 0, 300, 234);
    document.body.appendChild(canvas);

The first one is a normal resized image tag, and the second one is canvas. Notice how the canvas one is not as smooth. How can I achieve &#39;smoothness&#39;?

Resize image with javascript canvas (smoothly)

I&#39;m having trouble dealing with facebook&#39;s ReactJS. Whenever I do ajax and want to display an html data, ReactJS displays it as text. (See figure below)


![ReactJS render string][1]

The data is displayed through the success callback function of the jquery Ajax.

    $.ajax({
       url: url here,
       dataType: &quot;json&quot;,
       success: function(data) {
          this.setState({
               action: data.action
          })
       }.bind(this)
    });

![enter image description here][2]

Is there any easy way to convert this into html? How should I do it using ReactJS?


  [1]: http://i.stack.imgur.com/GK2ve.png
  [2]: http://i.stack.imgur.com/52Tq1.png

ReactJS convert HTML string to JSX

I am working on &#39;how to access elements randomly from an array in javascript&#39;. I found many links regarding this. Like:
https://stackoverflow.com/questions/5915096/get-random-item-from-array-with-jquery

    var item = items[Math.floor(Math.random()*items.length)];

But in this, we can choose only one item from the array. If we want more than one elements then how can we achieve this? How can we get more than one element from an array?


How to get a number of random elements from an array?

i&#39;m using the modal example from the bootstrap 3 docs. the modal works. however i need to access the show.bs.modal event when it fires. for now i&#39;m just trying: 

    $(&#39;#myModal&#39;).on(&#39;show.bs.modal&#39;, function () {
       alert(&#39;hi&#39;)
    })

Nothing happens, the event does not fire. What am I doing wrong??? This doesn&#39;t make sense to me. 

bootstrap jquery show.bs.modal event won&#39;t fire

I&#39;m receiving a date string from an API, and it is formatted as `yyyy-mm-dd`.

I am currently using a regex to validate the string format, which works ok, but I can see some cases where it could be a correct format according to the string but actually an invalid date. i.e. `2013-13-01`, for example.

Is there a better way in PHP to take a string such as `2013-13-01` and tell if it is a valid date or not for the format `yyyy-mm-dd`?



Correctly determine if date string is a valid date in that format

I am trying to convert `DateTime` format to `yyyy-MM-dd` format and store it to `DateTime` object. But it gives me the System `DateTime` format that is `MM/dd/yyyy`.  
I am using following code to convert.  

    string dateTime = DateTime.Now.ToString();
    string createddate = Convert.ToDateTime(dateTime).ToString(&quot;yyyy-MM-dd h:mm tt&quot;);         
    DateTime dt = DateTime.ParseExact(createddate, &quot;yyyy-MM-dd h:mm tt&quot;,CultureInfo.InvariantCulture);
    
            
but non of the above line converts into the specified format.  
Can any one help to solve this.

I am getting the DateTime from one application and passing this object to other application and That application is storing that date into MySql&#39;s DateTime field which is in the format &quot;yyyy-MM-dd&quot;.  
This is why I have posted this question.  

Project 1 has class from that I am getting the date.
and the processor class which is the middle ware of the application it processes the DateTime format to convert in specific format. And passes to the Other project which consumes the DateTime and stores that in the MySql field.

Convert DateTime in C# to yyyy-MM-dd format and Store it to MySql DateTime Field

My data can have multiple events on a given date or NO events on a date. I take these events, get a count by date and plot them.  However, when I plot them, my two series don&#39;t always match.    
   
    idx = pd.date_range(df[&#39;simpleDate&#39;].min(), df[&#39;simpleDate&#39;].max())
    s = df.groupby([&#39;simpleDate&#39;]).size()

    
In the above code **idx** becomes a range of say 30 dates. 09-01-2013 to 09-30-2013
However **S** may only have 25 or 26 days because no events happened for a given date. I then get an AssertionError as the sizes dont match when I try to plot:

    fig, ax = plt.subplots()    
    ax.bar(idx.to_pydatetime(), s, color=&#39;green&#39;)

What&#39;s the proper way to tackle this? Do I want to remove dates with no values from **IDX** or (which I&#39;d rather do) is add to the series the missing date with a count of 0. I&#39;d rather have a full graph of 30 days with 0 values. If this approach is right, any suggestions on how to get started? Do I need some sort of dynamic `reindex` function?

Here&#39;s a snippet of **S** ( `df.groupby([&#39;simpleDate&#39;]).size()`  ), notice no entries for 04 and 05.

    09-02-2013     2
    09-03-2013    10
    09-06-2013     5
    09-07-2013     1

Add missing dates to pandas dataframe

I have been facing a strange scenario when comparing dates in postgresql(version 9.2.4 in windows). 

I have a column in my table say `update_date` with type `timestamp without timezone`. &lt;br/&gt; Client can search over this field with only date (e.g: `2013-05-03`) or date with time (e.g.: `2013-05-03 12:20:00`).

This column has the value as timestamp for all rows currently and have the same date part `2013-05-03`, but difference in time part.

When I&#39;m comparing over this column, I&#39;m getting different results. Like the followings:

    select * from table where update_date &gt;= &#39;2013-05-03&#39; AND update_date &lt;= &#39;2013-05-03&#39; -&gt; No results
    
    select * from table where update_date &gt;= &#39;2013-05-03&#39; AND update_date &lt; &#39;2013-05-03&#39; -&gt; No results
    
    select * from table where update_date &gt;= &#39;2013-05-03&#39; AND update_date &lt;= &#39;2013-05-04&#39; -&gt; results found
    
    select * from table where update_date &gt;= &#39;2013-05-03&#39; -&gt; results found

My question is how can I make the first query possible to get results, I mean why the 3rd query is working but not the first one?


How to compare dates in datetime fields in Postgresql?

I&#39;m having a really hard time trying to find a way to iterate through this object in the way that I&#39;d like. I&#39;m using only Javascript here.

First, here&#39;s the object

    {
    &quot;dialog&quot;:
    {
        &quot;dialog_trunk_1&quot;:{
            &quot;message&quot;: &quot;This is just a JSON Test&quot;
        },
        
        &quot;dialog_trunk_2&quot;:{
            &quot;message&quot;: &quot;and a test of the second message&quot;
        },

        &quot;dialog_trunk_3&quot;:
        {
            &quot;message&quot;: &quot;This is a test of a bit longer text. Hopefully this will at the very least create 3 lines and trigger us to go on to another box. So we can test multi-box functionality, too.&quot;
        }
    }
    }

Right now, I&#39;m just trying basic ways to get through to each dialog_trunk on this object. I ideally want to loop through the object and for each trunk, display it&#39;s `message` value.

I&#39;ve tried using a for loop to generate the name/number of the dialog_trunk on the fly, but I can&#39;t access the object using a string for the object name so I&#39;m not sure where to go from here.

iterating through object

I have a JSON file containing some data I d like to access on my AngularJS website. Now what I want is to get only one object from the array. So I d like for example Item with id 1.

The data looks like this:

    { &quot;results&quot;: [
        {
            &quot;id&quot;: 1,
            &quot;name&quot;: &quot;Test&quot;
        },
        {
            &quot;id&quot;: 2,
            &quot;name&quot;: &quot;Beispiel&quot;
        },
        {
            &quot;id&quot;: 3,
            &quot;name&quot;: &quot;Sample&quot;
        }
    ] }

I d like to load the data with AngularJS $http functionality like this:

`$http.get(&quot;data/SampleData.json&quot;);`

which is working. But how can I now get a specific data object (by id) from the array I get from `$http.get` ?

Thanks in advance for your help.

Greets
Marc


Get specific object by id from array of objects in AngularJS

First off, I&#39;m using [Cheerio][1] for some DOM access and parsing with Node.js. Good times.

Heres the situation: 

I have a function that I need to create an object. That object uses variables for both its keys and values, and then return that single object. Example:

    stuff = function (thing, callback) {
      var inputs  = $(&#39;div.quantity &gt; input&#39;).map(function(){
        var key   = this.attr(&#39;name&#39;)
         ,  value = this.attr(&#39;value&#39;);

         return { key : value }
      }) 

      callback(null, inputs);
    }

It outputs this: 

    [ { key: &#39;1&#39; }, { key: &#39;1&#39; } ]

(`.map()` returns an array of objects fyi)

I need `key` to actually be the string from `this.attr(&#39;name&#39;)`.

Whats the best way to assign a string as a key in Javascript, considering what I&#39;m trying to do?

  [1]: https://github.com/MatthewMueller/cheerio

Creating object with dynamic keys

I have a object having some protected property that I want to get and set. The object looks like



    Fields_Form_Element_Location Object
    (
    [helper] =&gt; formText
    [_allowEmpty:protected] =&gt; 1
    [_autoInsertNotEmptyValidator:protected] =&gt; 1
    [_belongsTo:protected] =&gt; 
    

    [_description:protected] =&gt; 
    [_disableLoadDefaultDecorators:protected] =&gt; 
    [_errorMessages:protected] =&gt; Array
        (
        )

    [_errors:protected] =&gt; Array
        (
        )
    [_isErrorForced:protected] =&gt; 
    [_label:protected] =&gt; Current City
    

    [_value:protected] =&gt; 93399
    [class] =&gt; field_container field_19 option_1 parent_1
    )

I want to get `value` property of the object. When I try `$obj-&gt;_value` or `$obj-&gt;value` it generates error. I searched and found the solution to use `PHP Reflection Class`. It worked on my local but on server PHP version is `5.2.17` So I cannot use this function there. So any solution how to get such property?

How to get protected property of object in PHP

I am embedding a local pdf file into a simple webpage and I am looking to set the initial zoom to fit to the object size. Here is what I tried but it is not affecting the zoom.

     &lt;embed src=&quot;filename.pdf?zoom=50&quot; width=&quot;575&quot; height=&quot;500&quot;&gt;

does anyone know how to modify the code so its initial zoom is set to fit the object size.

Content Type	Original Author	Original Content on Stackoverflow
Question	Anoniem Anoniem	View Question on Stackoverflow
Solution 1 - Javascript	Boaz	View Answer on Stackoverflow
Solution 2 - Javascript	user1636522	View Answer on Stackoverflow
Solution 3 - Javascript	Matt Zeunert	View Answer on Stackoverflow

How to get the hours difference between two date objects?

Javascript Problem Overview

Javascript Solutions

Solution 1 - Javascript

Solution 2 - Javascript

Solution 3 - Javascript

Implicit "Submit" after hitting Done on the keyboard at the last EditText

Function to convert timestamp to human date in javascript

Attributions