DateTime Manipulation

I was looking for a resource which would explain all the possible options for formatting strings. I cam across http://www.blackwasp.co.uk/CSharpDateManipulation.aspx


DateTime theDate = DateTime.Parse("3 Jan 2007 21:25:30");
string result;

result = theDate.ToString("d-MM-yy"); // result = "3-01-07"
result = theDate.ToString("HH:mm"); // result = "21:25"
result = theDate.ToString("h:mm tt"); // result = "9:25 PM"


It's not an exhaustive list, but it solved my problem.

How to get the return value from an invoked application.

On the Windows operating system, an application’s return value is stored within a system environment variable named %ERRORLEVEL%. If you were to create an application that programmatically launches another executable, you can obtain the value of %ERRORLEVEL% using the static System.Diagnostics.Process.ExitCode property.

For example, the following program would return a value of "-1" when invoked:-

static int Main(string[] args)
{
// Display a message and wait for Enter key to be pressed.
Console.WriteLine("***** My First C# App *****");
Console.WriteLine("Hello World! ");
Console.WriteLine();
Console.ReadLine() ;
// Return an arbitrary error code.
return -1;
}


This program could then be called, and the return value evaluated, by using this following batch file for example:-

@echo off
rem A batch file for SimpleCSharpApp. exe
rem which captures the app' s return value.
SimpleCSharpApp
@if "%ERRORLEVEL%" == "0" goto success
: fail
echo This application has failed!
echo return value = %ERRORLEVEL%
goto end
: success
echo This application has succeeded!
echo return value = %ERRORLEVEL%
goto end
: end
echo All Done.


Tip - How to create a GUID

From - csharp-examples.net

using System.IO;

System.Guid.NewGuid().ToString()

// e.g. a12f98d0-4b36-4edc-99b1-83b6b871ab2c
System.Guid.NewGuid().ToString("N")

// e.g. bf4c57bccef54065ae85c88cc9bfd341
System.Guid.NewGuid().ToString("D")

// e.g. 544d1d5e-0cbb-4c4d-8def-de4f684b0d5d
System.Guid.NewGuid().ToString("B")

// e.g. {6b1ac215-4671-444b-9be2-04126c76e74d}
System.Guid.NewGuid().ToString("P")

// e.g.(db40c0e9-eca2-4123-aeae-c89847e48bba)


Tip - Get Files from Directory

From - csharp-examples.net



The method Directory.GetFiles returns string array with files names (full paths). For example:-





using System.IO;

string[] filePaths = Directory.GetFiles(@"c:\MyDir\");
// returns:
// "c:\MyDir\my-car.BMP"
// "c:\MyDir\my-house.jpg"





Get files from directory (with specified extension)

You can specify a search pattern. You can use wildcard specifiers in the search pattern, e.g. „*.bmp“ to select files with the extension or „a*“ to select files beginning with letter „a“.





using System.IO;

string[] filePaths = Directory.GetFiles(@"c:\MyDir\", "*.bmp");
// returns:
// "c:\MyDir\my-car.BMP"





Get files from directory (including all subdirectories)

If you want to search also in subfolders use parameter SearchOption.AllDirectories.





using System.IO;

string[] filePaths = Directory.GetFiles(@"c:\MyDir\", "*.bmp",
SearchOption.AllDirectories);
// returns:
// "c:\MyDir\my-car.BMP"
// "c:\MyDir\Friends\james.BMP"