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How can I make my own event in C#?
...
Here's an example of creating and using an event with C#
using System;
namespace Event_Example
{
//First we have to define a delegate that acts as a signature for the
//function that is ultimately called when the event is triggered.
//You wi...
Deserialize JSON with C#
...
It is important to note that the setters for the id and name properties must be left public. If they are set to private or protected, the deserialization will execute without error but all data will be null.
– Isaac Zais
Feb 19 '15 at 17:...
How do you use version control with Access development?
...s:
' Usage:
' CScript decompose.vbs <input file> <path>
' Converts all modules, classes, forms and macros from an Access Project file (.adp) <input file> to
' text and saves the results in separate files to <path>. Requires Microsoft Access.
'
Option Explicit
const ac...
SQL Switch/Case in 'where' clause
...ly below, you formed the SQL incorrectly. I tested mine in SQLServer 2005 and it worked fine.
– Bob Probst
Oct 16 '08 at 0:48
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Knight's Shortest Path on Chessboard
I've been practicing for an upcoming programming competition and I have stumbled across a question that I am just completely bewildered at. However, I feel as though it's a concept I should learn now rather than cross my fingers that it never comes up.
...
What's the @ in front of a string in C#?
...string verbatim = @"foo\bar";
string regular = "foo\\bar";
Here verbatim and regular have the same contents.
It also allows multi-line contents - which can be very handy for SQL:
string select = @"
SELECT Foo
FROM Bar
WHERE Name='Baz'";
The one bit of escaping which is necessary for verbatim s...
How to do exponentiation in clojure?
...ell: I'd recommend using this rather than going via Java interop since it handles all the Clojure arbitrary-precision number types correctly. It is in namespace clojure.math.numeric-tower.
It's called expt for exponentiation rather than power or pow which maybe explains why it's a bit hard to find ...
When should I use a composite index?
..._C )
will benefit a query that uses those fields for joining, filtering, and sometimes selecting. It will also benefit queries that use left-most subsets of columns in that composite. So the above index will also satisfy queries that need
index( column_A, column_B, column_C )
index( column_A, col...
What is the curiously recurring template pattern (CRTP)?
...ts specialization for any type X will be inherited from singleton<X> and thus will have all its (public, protected) members accessible, including the GetInstance! There are other useful uses of CRTP. For example, if you want to count all instances that currently exist for your class, but want ...
Python pandas: fill a dataframe row by row
...sign a dictionary
to each element of the row y probably not what you want; converting to a Series tells pandas
that you want to align the input (for example you then don't have to to specify all of the elements)
In [7]: df = pandas.DataFrame(columns=['a','b','c','d'], index=['x','y','z'])
In [8]: ...