Thursday, December 17, 2009

Implementing Login Authentication in WPF Application






connectionString="server=.\SQLEXPRESS;database=ASCO_DB;integrated security=sspi;"/>






name="AspNetSqlMembershipProvider"
type="System.Web.Security.SqlMembershipProvider,System.Web"
connectionStringName="LocalSqlServer"
enablePasswordRetrieval="false"
enablePasswordReset="true"
requiresQuestionAndAnswer="true"
applicationName="/"
requiresUniqueEmail="false"
passwordFormat="Hashed"
maxInvalidPasswordAttempts="5"
minRequiredPasswordLength="7"
minRequiredNonalphanumericCharacters="0"
passwordAttemptWindow="10"
passwordStrengthRegularExpression="" />



Thursday, October 29, 2009

Nullable in c#

Nullable is used for assigning null value to a variable. For example we have a variable for finding user's selection of Gender . If the user doesn't select any option we should get an information .Here comes the advantage of using nullable. There are two ways to use nullable option in c#.

1) bool? blnVar =null;


if( b.HasValue )
{
Console.WriteLine(b.value);
}
else
{
Console.WriteLine("Value not set for b");
}
2) Nullable blnVar=null;
in this manner also we can obtain the HasValue

Wednesday, March 18, 2009

Run commands

Program--------------- Commands

Add/Remove Programs-----------
-----------appwiz.cpl
Administrative tools control
----------------admintools
Adobe acrobat
---------------------------------acrobat
Adobe ImageReady
---------------------------imageready
Adobe Photoshop
-----------------------------photoshop
Basic Media Player
---------------------------mplay32
Blue tooth transfer Wizard-----------------fsquirt
Calculator------------------------------------calc
Check disk Utility----------------------------chkdsk
Command prompt----------------------------cmd
Command prompt---------------------------command
Component Services-------------------------dcomcnfg
Computer Managment----------------------compmgmt.msc
compare Files--------------------------------comp
Control Panel--------------------------------control


Friday, February 6, 2009

Windows service detecting USB

When i got a chance to create an application on USB detection i used WndProc method which will be receiving the Windows Messages. But in the case of a service creation it never helped me . Then i went through other message tracking part which was quiet interesting .
here i m loading my exe whenever a USB is inserted . The exe path is being read from my registry .



using System;
using System.IO;
using System.Runtime.InteropServices;
using System.ServiceProcess;
using System.Text;
using System.Diagnostics;
using Microsoft.Win32;
namespace USBDetectionService
{
public partial class Service1 : ServiceBase
{
#region Fields
private FileSystemWatcher fileSystemWatcher;
private IntPtr deviceNotifyHandle;
private IntPtr directoryHandle;
private Win32.ServiceControlHandlerEx myCallback;

#endregion

#region USB Detection

private int ServiceControlHandler(int control, int eventType, IntPtr eventData, IntPtr context)
{
if (control == Win32.SERVICE_CONTROL_STOP || control == Win32.SERVICE_CONTROL_SHUTDOWN)
{
UnregisterHandles();
Win32.UnregisterDeviceNotification(this.ServiceHandle);

base.Stop();
}
else if (control == Win32.SERVICE_CONTROL_DEVICEEVENT)
{
switch (eventType)
{
case Win32.DBT_DEVICEARRIVAL:
try
{
Registry.LocalMachine.OpenSubKey("SOFTWARE", true);
RegistryKey masterKey = Registry.LocalMachine.CreateSubKey("SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\App Paths\\FlukeAppPath");
string strProcessName = "";
if (masterKey != null)
{
strProcessName = masterKey.GetValue("PATH").ToString();
string strExeName = System.IO.Path.GetFileName(strProcessName);
strExeName = strExeName.Substring(0, strExeName.Length - 4);
Process[] pname = Process.GetProcessesByName(strExeName);
if (pname.Length == 0)
{
Process.Start(strProcessName);
}
}
masterKey.Close();
}
catch (Exception e)
{
}
break;

case Win32.DBT_DEVICEQUERYREMOVE:
UnregisterHandles();
fileSystemWatcher.EnableRaisingEvents = false;
break;
}
}

return 0;
}

private void UnregisterHandles()
{
if (directoryHandle != IntPtr.Zero)
{
Win32.CloseHandle(directoryHandle);
directoryHandle = IntPtr.Zero;
}
if (deviceNotifyHandle != IntPtr.Zero)
{
Win32.UnregisterDeviceNotification(deviceNotifyHandle);
deviceNotifyHandle = IntPtr.Zero;
}
}

private void RegisterForHandle(char c)
{
Win32.DEV_BROADCAST_HANDLE deviceHandle = new Win32.DEV_BROADCAST_HANDLE();
int size = Marshal.SizeOf(deviceHandle);
deviceHandle.dbch_size = size;
deviceHandle.dbch_devicetype = Win32.DBT_DEVTYP_HANDLE;
directoryHandle = CreateFileHandle(c + ":\\");
deviceHandle.dbch_handle = directoryHandle;
IntPtr buffer = Marshal.AllocHGlobal(size);
Marshal.StructureToPtr(deviceHandle, buffer, true);
deviceNotifyHandle = Win32.RegisterDeviceNotification(this.ServiceHandle, buffer, Win32.DEVICE_NOTIFY_SERVICE_HANDLE);
if (deviceNotifyHandle == IntPtr.Zero)
{
// TODO handle error
}
}

private void RegisterDeviceNotification()
{
myCallback = new Win32.ServiceControlHandlerEx(ServiceControlHandler);
Win32.RegisterServiceCtrlHandlerEx(this.ServiceName, myCallback, IntPtr.Zero);

if (this.ServiceHandle == IntPtr.Zero)
{
// TODO handle error
}

Win32.DEV_BROADCAST_DEVICEINTERFACE deviceInterface = new Win32.DEV_BROADCAST_DEVICEINTERFACE();
int size = Marshal.SizeOf(deviceInterface);
deviceInterface.dbcc_size = size;
deviceInterface.dbcc_devicetype = Win32.DBT_DEVTYP_DEVICEINTERFACE;
IntPtr buffer = default(IntPtr);
buffer = Marshal.AllocHGlobal(size);
Marshal.StructureToPtr(deviceInterface, buffer, true);
IntPtr r = default(IntPtr);
r = Win32.RegisterDeviceNotification(this.ServiceHandle, buffer, Win32.DEVICE_NOTIFY_SERVICE_HANDLE | Win32.DEVICE_NOTIFY_ALL_INTERFACE_CLASSES);
if (r == IntPtr.Zero)
{
// TODO handle error
}
}

#endregion

public Service1()
{
InitializeComponent();
}

#region Events

void fileSystemWatcher_Created(object sender, System.IO.FileSystemEventArgs e)
{
// TODO handle event
}

void fileSystemWatcher_Renamed(object sender, System.IO.RenamedEventArgs e)
{
// TODO handle event
}

void fileSystemWatcher_Changed(object sender, System.IO.FileSystemEventArgs e)
{
// TODO handle event
}

void fileSystemWatcher_Deleted(object sender, System.IO.FileSystemEventArgs e)
{
// TODO handle event
}

#endregion

#region Private Helper Methods

public static IntPtr CreateFileHandle(string driveLetter)
{
// open the existing file for reading
IntPtr handle = Win32.CreateFile(
driveLetter,
Win32.GENERIC_READ,
Win32.FILE_SHARE_READ | Win32.FILE_SHARE_WRITE,
0,
Win32.OPEN_EXISTING,
Win32.FILE_FLAG_BACKUP_SEMANTICS | Win32.FILE_ATTRIBUTE_NORMAL,
0);

if (handle == Win32.INVALID_HANDLE_VALUE)
{
return IntPtr.Zero;
}
else
{
return handle;
}
}

#endregion

#region ServiceBase Implementation

protected override void OnStart(string[] args)
{
base.OnStart(args);

RegisterDeviceNotification();

fileSystemWatcher = new FileSystemWatcher();
fileSystemWatcher.Created += new System.IO.FileSystemEventHandler(fileSystemWatcher_Created);
fileSystemWatcher.Deleted += new System.IO.FileSystemEventHandler(fileSystemWatcher_Deleted);
fileSystemWatcher.Changed += new System.IO.FileSystemEventHandler(fileSystemWatcher_Changed);
fileSystemWatcher.Renamed += new System.IO.RenamedEventHandler(fileSystemWatcher_Renamed);
}

#endregion
}

public class Win32
{
public const int DEVICE_NOTIFY_SERVICE_HANDLE = 1;
public const int DEVICE_NOTIFY_ALL_INTERFACE_CLASSES = 4;

public const int SERVICE_CONTROL_STOP = 1;
public const int SERVICE_CONTROL_DEVICEEVENT = 11;
public const int SERVICE_CONTROL_SHUTDOWN = 5;

public const uint GENERIC_READ = 0x80000000;
public const uint OPEN_EXISTING = 3;
public const uint FILE_SHARE_READ = 1;
public const uint FILE_SHARE_WRITE = 2;
public const uint FILE_SHARE_DELETE = 4;
public const uint FILE_ATTRIBUTE_NORMAL = 128;
public const uint FILE_FLAG_BACKUP_SEMANTICS = 0x02000000;
public static readonly IntPtr INVALID_HANDLE_VALUE = new IntPtr(-1);

public const int DBT_DEVTYP_DEVICEINTERFACE = 5;
public const int DBT_DEVTYP_HANDLE = 6;

public const int DBT_DEVICEARRIVAL = 0x8000;
public const int DBT_DEVICEQUERYREMOVE = 0x8001;
public const int DBT_DEVICEREMOVECOMPLETE = 0x8004;

public const int WM_DEVICECHANGE = 0x219;

public delegate int ServiceControlHandlerEx(int control, int eventType, IntPtr eventData, IntPtr context);

[DllImport("advapi32.dll", SetLastError = true)]
public static extern IntPtr RegisterServiceCtrlHandlerEx(string lpServiceName, ServiceControlHandlerEx cbex, IntPtr context);

[DllImport("kernel32.dll", SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
public static extern bool GetVolumePathNamesForVolumeNameW(
[MarshalAs(UnmanagedType.LPWStr)]
string lpszVolumeName,
[MarshalAs(UnmanagedType.LPWStr)]
string lpszVolumePathNames,
uint cchBuferLength,
ref UInt32 lpcchReturnLength);

[DllImport("kernel32.dll")]
public static extern bool GetVolumeNameForVolumeMountPoint(string
lpszVolumeMountPoint, [Out] StringBuilder lpszVolumeName,
uint cchBufferLength);

[DllImport("user32.dll", SetLastError = true)]
public static extern IntPtr RegisterDeviceNotification(IntPtr IntPtr, IntPtr NotificationFilter, Int32 Flags);

[DllImport("user32.dll", CharSet = CharSet.Auto)]
public static extern uint UnregisterDeviceNotification(IntPtr hHandle);

[DllImport("kernel32.dll", SetLastError = true)]
public static extern IntPtr CreateFile(
string FileName, // file name
uint DesiredAccess, // access mode
uint ShareMode, // share mode
uint SecurityAttributes, // Security Attributes
uint CreationDisposition, // how to create
uint FlagsAndAttributes, // file attributes
int hTemplateFile // handle to template file
);

[DllImport("kernel32.dll", SetLastError = true)]
public static extern bool CloseHandle(IntPtr hObject);

[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
public struct DEV_BROADCAST_DEVICEINTERFACE
{
public int dbcc_size;
public int dbcc_devicetype;
public int dbcc_reserved;
[MarshalAs(UnmanagedType.ByValArray, ArraySubType = UnmanagedType.U1, SizeConst = 16)]
public byte[] dbcc_classguid;
[MarshalAs(UnmanagedType.ByValArray, SizeConst = 128)]
public char[] dbcc_name;
}

[StructLayout(LayoutKind.Sequential)]
public struct DEV_BROADCAST_HDR
{
public int dbcc_size;
public int dbcc_devicetype;
public int dbcc_reserved;
}

[StructLayout(LayoutKind.Sequential)]
public struct DEV_BROADCAST_HANDLE
{
public int dbch_size;
public int dbch_devicetype;
public int dbch_reserved;
public IntPtr dbch_handle;
public IntPtr dbch_hdevnotify;
public Guid dbch_eventguid;
public long dbch_nameoffset;
public byte dbch_data;
public byte dbch_data1;
}
}
}

Thursday, January 22, 2009

Embedded application Development

As any application development Embedded application development requires sufficient thoughts.............................
we will start from the OS selection.....

OS selection should be based on
1)The functional needs of the application.
2)Availability of development tools and technical support.
3)Third party application and developer support.
4)Real time capabilities.
5)Processor architecture and peripheral support.
6)Memory foot print.
7)business Model.
8)Conformance to standards

What is real time operating system ?
Real time operating system can be defined as an OS which guarantees a certain capability with in a specified time span.Real time operating systems are commonly found in Robotics,complex multimedia and animations , communications and has various military and government uses.

Some examples of real-time operating systems are Chimera, Lynx, MTOS, QNX, RTMX, RTX, and VxWorks.



Tuesday, January 13, 2009

Copying Listview data to ClipBoard C#

Its pretty interesting working around with a listview. Most of the time we use export to excel functionality to copy the list item.In this case we might be required to take care of the version of Excel and all those complex stuff.Clip board is a cool solution for this problem . so lets find out how we can copy selected items in a list view to Clipboard.



string strToClipbrd=""; //stores the items in list view
foreach (ColumnHeader columnHeader in listview.Columns)
{
strClipBrd = strClipBrd + columnHeader.Text+"\t"; // \t help us to navigate to nextcell
}
strClipBrd = strClipBrd + columnHeader.Text+"\n"; // to the new line or to the next row
for (int i = 0; i < listview.Items.Count; i++)
{
for (int j = 0; j < listview.Columns.Count; j++)
{
if (listview.Items[i].Selected == true) //only selected rows are allowed
strToClipbrd= strToClipbrd+ listview.Items[i].SubItems[j].Text + "\t";
}
strToClipbrd= strToClipbrd+ "\n";
}
Clipboard.SetDataObject(strToClipbrd, true);