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is_null($x) vs $x === null in PHP [duplicate]
PHP has two (that I know of, and three if you count isset() ) methods to determine if a value is null: is_null() and === null . I have heard, but not confirmed, that === null is faster, but in a code review someone strongly suggested that I use is_null() instead as it is specifically design...
Detect home button press in android
This has been driving me nuts for a while now.
17 Answers
17
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How do I make an HTML text box show a hint when empty?
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That is known as a textbox watermark, and it is done via JavaScript.
http://naspinski.net/post/Text-Input-Watermarks-using-Javascript-(IE-Compatible).aspx
or if you use jQuery, a much better approach:
http://digitalbush.com/proj...
How to simulate the environment cron executes a script with?
...e, turn it back off, then run
env - `cat ~/cronenv` /bin/sh
And you are now inside a sh session which has cron's environment
Bring your environment to cron
You could skip above exercise and just do a . ~/.profile in front of your cron job, e.g.
* * * * * . ~/.profile; your_command
Use screen
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Using bootstrap with bower
...p in your workflow.
It's a matter of choice I guess.
Update : seems they now version a dist folder (see: https://github.com/twbs/bootstrap/pull/6342), so just use bower install bootstrap and point to the assets in the dist folder
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How do you convert a DataTable into a generic list?
...(DateTime )); for(int i=0;i<=1000;i++){dt.Rows.Add(i, "foo", DateTime.Now);}
– Rahul Garg
Jul 25 '18 at 10:56
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MySQL: Set user variable from result of query
...ame} and this '{variable_name}', we can replace it with our variable name.
Now, how to assign a value in a variable in mysql. For this we have many ways to do that
Using keyword 'SET'.
Example :-
mysql > SET @a = 1;
Without using keyword 'SET' and using ':='.
Example:-
mysql > @a:=1;
B...
Checkout subdirectories in Git?
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Sparse checkouts are now in Git 1.7.
Also see the question “Is it possible to do a sparse checkout without checking out the whole repository first?”.
Note that sparse checkouts still require you to download the whole repository, even though...
Apply multiple functions to multiple groupby columns
... 0.687672 1.754877 0.672401
Using apply and returning a Series
Now, if you had multiple columns that needed to interact together then you cannot use agg, which implicitly passes a Series to the aggregating function. When using apply the entire group as a DataFrame gets passed into the fu...
Why should you remove unnecessary C# using directives?
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Now that's what I wanted to hear :-) I am used doing a Organize Usings -> Remove and Sort every now and then. BTW, to me the upper two options in Organize Usings are meaningless. I am talking about VS2013 btw.
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