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Get epoch for a specific date using Javascript
...ernet Explorer. Date constructor relies on the Date.parse() method when a string is passed, which is implementation dependant in ECMA-262 3rd edition and, as a result, notoriously inflexible in IE.
– Andy E
Jul 30 '10 at 7:50
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Open file dialog and select a file using WPF controls and C#
...a TextBox
if (result == true)
{
// Open document
string filename = dlg.FileName;
textBox1.Text = filename;
}
}
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Run an exe from C# code
...void LaunchCommandLineApp()
{
// For the example
const string ex1 = "C:\\";
const string ex2 = "C:\\Dir";
// Use ProcessStartInfo class
ProcessStartInfo startInfo = new ProcessStartInfo();
startInfo.CreateNoWindow = false;
startInfo.UseShe...
How to Test a Concern in Rails
...t I have a Personable concern in my Rails 4 application which has a full_name method, how would I go about testing this using RSpec?
...
SQLite select where empty?
...e faster in some situation, as comparing numbers is simpler than comparing strings. If the performance for that is a concern, you should of course check what it does.
– Guffa
Apr 16 '12 at 11:16
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How to check if a model has a certain column/attribute?
... a class
Use Class.column_names.include? attr_name where attr_name is the string name of your attribute.
In this case: Number.column_names.include? 'one'
For an instance
Use record.has_attribute?(:attr_name) or record.has_attribute?('attr_name') (Rails 3.2+) or record.attributes.has_key? attr_na...
Is there a Newline constant defined in Java like Environment.Newline in C#?
...PI : System.lineSeparator
Returns the system-dependent line separator string. It always returns
the same value - the initial value of the system property
line.separator. On UNIX systems, it returns "\n"; on Microsoft Windows
systems it returns "\r\n".
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Multiple submit buttons in an HTML form
...alls for a lot of trouble. Even the simple case: "we should abbreviate the string to 'Prev. Page' " will ruin your sites functionality.
– Tylla
May 4 at 23:30
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MongoDB - Update objects in a document's array (nested updating)
...reak it into two parts. First, increment any document that has "items.item_name" equal to "my_item_two". For this you'll have to use the positional "$" operator. Something like:
db.bar.update( {user_id : 123456 , "items.item_name" : "my_item_two" } ,
{$inc : {"items.$.price" : ...
postgresql COUNT(DISTINCT …) very slow
...
You can use this:
SELECT COUNT(*) FROM (SELECT DISTINCT column_name FROM table_name) AS temp;
This is much faster than:
COUNT(DISTINCT column_name)
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