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get size of json object
... check the size i.e. like that:
var data = {one : 1, two : 2, three : 3};
_.size(data);
//=> 3
_.keys(data);
//=> ["one", "two", "three"]
_.keys(data).length;
//=> 3
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Qt 5.1.1: Application failed to start because platform plugin “windows” is missing
...roblem . After a long search I found a comment which had been ignored by all users pointing to the missing lib. Now, many months later, the comment has been changed to an answer. However, when I answered this question by msyself I intended to help other people by directly providing the solution. T...
How to add column if not exists on PostgreSQL?
...statement:
DO $$
BEGIN
BEGIN
ALTER TABLE <table_name> ADD COLUMN <column_name> <column_type>;
EXCEPTION
WHEN duplicate_column THEN RAISE NOTICE 'column <column_name> already exists in <table_name>.';
END;
END;
$$
...
Force to open “Save As…” popup open at text link click for PDF in HTML
... the time of this comment, I've tested it on Chrome, Opera, Edge, Mozilla. All latest. Is working on all except on Mozilla.
– S.I.
Sep 29 '17 at 5:07
7
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Can I use jQuery with Node.js?
...
Note: The original answer fails to mention that it you will need to install jsdom as well using npm install jsdom
Update (late 2013): The official jQuery team finally took over the management of the jquery package on npm:
npm install jquery
Then:
require("jsdom").env("", function (err, wind...
Pandas every nth row
...simpler solution to the accepted answer that involves directly invoking df.__getitem__.
df = pd.DataFrame('x', index=range(5), columns=list('abc'))
df
a b c
0 x x x
1 x x x
2 x x x
3 x x x
4 x x x
For example, to get every 2 rows, you can do
df[::2]
a b c
0 x x x
...
How to use dashes in HTML-5 data-* attributes in ASP.NET MVC
...an underscore.
For example:
@Html.TextBoxFor(vm => vm.City, new { data_bind = "foo" })
will render this in MVC 3:
<input data-bind="foo" id="City" name="City" type="text" value="" />
If you're still using an older version of MVC, you can mimic what MVC 3 is doing by creating this sta...
Preserve Line Breaks From TextArea When Writing To MySQL
...
Out of all the answers, this one is least concise
– JacobRossDev
Aug 14 '15 at 21:04
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Why have header files and .cpp files? [closed]
...dencies so that code that uses the header doesn't necessarily need to know all the details of the implementation and any other classes/headers needed only for that. This will reduce compilation times and also the amount of recompilation needed when something in the implementation changes.
It's not ...
Which is best way to define constants in android, either static class, interface or xml resource?
... advantages of using project resources is the ease of access and that they allow you to organize your project significantly.
static final constants are compiled into the java bytecode; project resources are compiled into a binary format within the apk. Accessing either is extremely efficient... if ...