PHP Database Connection

<?php
class DB {
private $_connection;
private static $_instance; //The single instance
private $_host = "localhost";
private $_username = "root";
private $_password = "";
private $_database = "database";
/*
Get an instance of the Database
@return Instance
*/
public static function getInstance() {
if(!self::$_instance) { // If no instance then make one
self::$_instance = new self();
}
return self::$_instance;
}
// Constructor
private function __construct() {
$this->_connection = new mysqli($this->_host, $this->_username,
$this->_password, $this->_database);

// Error handling
if(mysqli_connect_error()) {
trigger_error("Failed to conencto to MySQL: " . mysql_connect_error(),
E_USER_ERROR);
}
}
// Magic method clone is empty to prevent duplication of connection
private function __clone() { }
// Get mysqli connection
public function getConnection() {
return $this->_connection;
}
}
?>

Delphi SendMessage of string

This is how you sendmessage a string passing it either WParam or LParam.

procedure MySenderFunction;
var
 sText: String;   
begin
    sText := 'This is a test'.
     SendMessage(Handle, WM_MYMESSAGE, Integer(@sText), 0) ;
end;


This is how you get the parameter being passed.

procedure MySenderFunction(Msg: TMessage);
var
    sText: String;
begin
    sText := PString(Msg.WParam)^;
end;

Delphi Stream to String

String grid filter

procedure MyFilter(AFilter: String);
begin
   grid.Filter.Clear;
  with grid.Filter.Add do
  begin
    Condition:=AFilter;
    Column:=1;
  end;

  grid.FilterActive:=active;
end;

Checking if a folder is empty.

function IsDirectoryEmpty(const ADirectory: String): Boolean;
var
  searchRec: TSearchRec;
begin
   try

Result := (FindFirst(ADirectory+'\*.*', faAnyFile, searchRec) = 0) AND
  (FindNext(searchRec) = 0) AND
  (FindNext(searchRec) <> 0);

   finally
     FindClose(searchRec);
   end;
end;

Block Alt-F4 in Delphi

procedure TForm1.FormKeyDown(Sender: TObject; var Key: Word; Shift: TShiftState);
begin
  if (Key = VK_F4) and (ssAlt in Shift) then
       Key := 0;
end;

How to Minimize All Windows

uses ComObj;

procedure MinimizeAll;
var
  Shell : OleVariant;
begin
  try
   Shell := CreateOleObject('Shell.Application') ;
   Shell.MinimizeAll;
  finally
  end;
end;