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MongoDB SELECT COUNT GROUP BY
...
I need some extra operation based on the result of aggregate function. Finally I've found some solution for aggregate function and the operation based on the result in MongoDB. I've a collection Request with field request, source, status...
CodeIgniter removing index.php from url
...g on hosting server. In some hosting server (e.g.: Godaddy) need to use an extra ? in the last line of above code. The following line will be replaced with last line in applicable case:
// Replace last .htaccess line with this line
RewriteRule ^(.*)$ index.php?/$1 [L,QSA]
...
“register” keyword in C?
...at the variable does not alias with
anything else in the program (not even char's).
That can be exploited by modern compilers in a variety of situations, and can help the compiler quite a bit in complex code - in simple code the compilers can figure this out on their own.
Otherwise, it serves no p...
Easiest way to read from and write to files
...and File.WriteAllText.
MSDN example excerpt:
// Create a file to write to.
string createText = "Hello and Welcome" + Environment.NewLine;
File.WriteAllText(path, createText);
...
// Open the file to read from.
string readText = File.ReadAllText(path);
...
What does extern inline do?
... StackOverflow)
#ifdef __cplusplus
#include <cstdio>
#include <cstring>
#else
#include <stdio.h>
#include <string.h>
#endif
//=========== MACRO MAGIC BEGINS ============
//Trim full file path
#define __SFILE__ (strrchr(__FILE__,'/') ? strrchr(__FILE__,'/')+1 : __FILE__...
What is the lifetime of a static variable in a C++ function?
...r of construction must be taken into account.
Example
struct emitter {
string str;
emitter(const string& s) : str(s) { cout << "Created " << str << endl; }
~emitter() { cout << "Destroyed " << str << endl; }
};
void foo(bool skip_first)
{
if ...
How to do ToString for a possibly null object?
...# 6.0 we can now have a succinct, cast-free version of the orignal method:
string s = myObj?.ToString() ?? "";
Or even using interpolation:
string s = $"{myObj}";
Original Answer:
string s = (myObj ?? String.Empty).ToString();
or
string s = (myObjc ?? "").ToString()
to be even more concise.
Unfo...
How to put a new line into a wpf TextBlock control?
...
baz bar</data>
If that does not work you might need to parse the string manually.
If you need direct XAML that's easy by the way:
<TextBlock>
Lorem <LineBreak/>
Ipsum
</TextBlock>
share...
What's the difference between SoftReference and WeakReference in Java?
...ort java.util.HashMap;
public class Test {
public static void main(String args[]) {
HashMap<Employee, EmployeeVal> aMap = new
HashMap<Employee, EmployeeVal>();
Employee emp = new Employee("Vinoth");
EmployeeVal val = new EmployeeVa...
Script entire database SQL-Server
...d and when.
We wanted to allow our Wix MSI installer to specify connection string and credentials, and needed some way to pass these into the scripts, so once again, using tokens and some conditional logic.
Example script (edited for brevity)
-- Sleep: 5
-- Sleep after creating database to allow...