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Getting a random value from a JavaScript array
...s to performance optimization while producing output using UI elements, ~~ wins the game. MORE INFO
var rand = myArray[~~(Math.random() * myArray.length)];
But if you know that the array is going to have millions of elements than you might want to reconsider between Bitwise Operator and Math.Floor(...
Overriding a Rails default_scope
...rder('created_at desc')
end
Foo.reorder('created_at asc')
runs the following SQL:
SELECT * FROM "foos" ORDER BY created_at asc
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How to convert QString to std::string?
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std::string utf8_text = qs.toUtf8().constData();
// or this if you're on Windows :-)
std::string current_locale_text = qs.toLocal8Bit().constData();
The suggested (accepted) method may work if you specify codec.
See: http://doc.qt.io/qt-5/qstring.html#toLatin1
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Could not load file or assembly 'System.Data.SQLite'
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I'm running windows 7, and I hit this issue; turning 32-bit on fixed it for me, presumably because my copy of the DLL was 32-bit.
– Doug
Jul 12 '11 at 3:41
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Determine which MySQL configuration file is being used
...-help | grep -A 1 "Default options"
Default options are read from the following files in the given order:
/etc/mysql/my.cnf ~/.my.cnf /usr/etc/my.cnf
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Load image from resources area of project in C#
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Are you using Windows Forms? If you've added the image using the Properties/Resources UI, you get access to the image from generated code, so you can simply do this:
var bmp = new Bitmap(WindowsFormsApplication1.Properties.Resources.myima...
Install an apk file from command prompt?
I want to install a file using the Windows command line. First I want to build after compiling all the .jar files to create an .apk file for an Android application without using Eclipse.
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Changing website favicon dynamically
...d here). Here is a different demo of code that works in IE11 too. The following example might not work in Safari or Internet Explorer.
/*!
* Dynamically changing favicons with JavaScript
* Works in all A-grade browsers except Safari and Internet Explorer
* Demo: http://mathiasbynens.be/demo/dyna...
How can I “pretty print” a Duration in Java?
...me has a pretty good way to do this using a PeriodFormatterBuilder.
Quick Win: PeriodFormat.getDefault().print(duration.toPeriod());
e.g.
//import org.joda.time.format.PeriodFormatter;
//import org.joda.time.format.PeriodFormatterBuilder;
//import org.joda.time.Duration;
Duration duration = new ...
What are the undocumented features and limitations of the Windows FINDSTR command?
The Windows FINDSTR command is horribly documented. There is very basic command line help available through FINDSTR /? , or HELP FINDSTR , but it is woefully inadequate. There is a wee bit more documentation online at https://docs.microsoft.com/en-us/windows-server/administration/windows-commands...