Re: windows not in focus - C# Discussion Boards

Heinzzy17-Jan-10 5:50

Heinzzy

17-Jan-10 5:50

So, we have a result here. To accomplish the mission you should definitly create a service. With hooks! Wink | ;)

wjp_auhtm17-Jan-10 5:27

17-Jan-10 5:27

I think that you need create a windows service. When the computer got data, the service app show the data on the form's textbox, even the form unfocused.

michaelgr117-Jan-10 5:28

17-Jan-10 5:28

OK how can i do it using my application?

wjp_auhtm17-Jan-10 18:33

17-Jan-10 18:33

Oh!
I try to open a win app from a windows service, but I was failed.
I consider that creating a socket connect between the windows service and the win app may be practicable.

creating windows service like this.

creating socket like this.

michaelgr117-Jan-10 20:06

17-Jan-10 20:06

OK. But i have another question-

If i create a windows service to manage the data from the barcode reader (the data will go to clipboard and then set focus to my application),
How can i install this windows service on a user computer (without installutil etc.)?

wjp_auhtm17-Jan-10 21:24

17-Jan-10 21:24

You could install the windows service like this, if u are using .Net FrameWork 3.5.

I found that the file named "System.Configuration.Install.dll" in .Net 2.0 is different from the .Net 3.5's.

There are some simple code.

using System.ServiceProcess;
using System.Configuration.Install;
using System.Collections;

            /// <summary>
            /// TODO: Is the service is existed and return true or false.
            /// </summary>
            /// <param name=" NameService ">Name of the windows service.</param>
            /// <returns>If the service is existed then return true,or return false.</returns>
            private bool isServiceIsExisted(string NameService) 
            {
                ServiceController[] services = ServiceController.GetServices();
                foreach (ServiceController s in services) 
                {
                    if (s.ServiceName.ToLower() == NameService.ToLower()) 
                    {
                        return true;
                    }
                }
                return false;
            }

            /// <summary>
            /// TODO: Install windows service.
            /// </summary>
            /// <param name="stateSaver">Collection(default is Null)</param>
            /// <param name="filepath">Full path of the windows service file</param>
            private void InstallmyService(IDictionary stateSaver, string filepath)
            {
                AssemblyInstaller AssemblyInstaller1 = new AssemblyInstaller();
                AssemblyInstaller1.UseNewContext = true;
                AssemblyInstaller1.Path = filepath;
                AssemblyInstaller1.Install(stateSaver);
                AssemblyInstaller1.Commit(stateSaver);
                AssemblyInstaller1.Dispose();
            }
            /// <summary>
            /// TODO: Uninstall windows service.
            /// </summary>
            /// <param name="filepath">Full path of the windows service file</param>
            private void UnInstallmyService(string filepath)
            {
                AssemblyInstaller AssemblyInstaller1 = new AssemblyInstaller();
                AssemblyInstaller1.UseNewContext = true;
                AssemblyInstaller1.Path = filepath;
                AssemblyInstaller1.Uninstall(null);
                AssemblyInstaller1.Dispose();
            }

Good Luck!

michaelgr117-Jan-10 21:35

17-Jan-10 21:35

Will this code start the service too?

wjp_auhtm17-Jan-10 21:57

17-Jan-10 21:57

If set the windows service autorun, when you restart computer, the service will start.

Of course, you can start the service in manual like this.

/// <summary>
/// TODO: Start windows service.
/// </summary>
/// <param name="name">The name of windows service.</param>
/// <returns>If success return true,or return false.;</returns>
private bool StarmyService(string name)
{
    ServiceController sc = new ServiceController(name);
    if (sc.Status == ServiceControllerStatus.Stopped || sc.Status == ServiceControllerStatus.StopPending
            )
    {
        sc.Start();
        sc.WaitForStatus(ServiceControllerStatus.Running, new TimeSpan(0, 0, 10));
    }
    else
    {
    }
    sc.Close();
    return true;
}

And stop the service like this

/// <summary>
/// TODO: Stop windows service.
/// </summary>
/// <param name="name">The name of windows service.</param>
/// <returns>If success return true,or return false.;</returns>
private bool StopmyService(string name)
{
    ServiceController sc = new ServiceController(name);
    if (sc.Status == ServiceControllerStatus.Running ||
        sc.Status == ServiceControllerStatus.StartPending)
    {
        sc.Stop();
        sc.WaitForStatus(ServiceControllerStatus.Stopped, new TimeSpan(0, 0, 10));
    }
    else
    {
    }
    sc.Close();
    return true;
}

michaelgr117-Jan-10 22:00

17-Jan-10 22:00

OK and how can i set the service to start automatically ? i mean in the service code.
Also how can i check if the service is already running?

wjp_auhtm17-Jan-10 22:26

17-Jan-10 22:26

OK, the simple code to check if the service is running like this.

/// <summary>
/// TODO: Is the windows service running.
/// </summary>
/// <param name="name">The name of windows service.</param>
private bool IsRunning(string name)
{
    bool IsRun = false;
    if (!isServiceIsExisted(name)) // this function was named previously.
    {
        return false;
    }
    ServiceController sc = new ServiceController(name);
    if (sc.Status == ServiceControllerStatus.StartPending ||
        sc.Status == ServiceControllerStatus.Running)
    {
        IsRun = true;
    }
    sc.Close();

    return IsRun;
}

Set the service to start automatically：
Change the value of property named "StartType" of the windows service to "Automatic".

BTW, owing to the limitation of my knowledge, the code are not very strong.I suggest that you can research them by yourself. I think that after you reserach them, you will learn more.

michaelgr117-Jan-10 22:39

17-Jan-10 22:39

OK , and how can i set the service to start automaticallu ? i mean programatically?

also how do i check if the service is already running? or it's not matter?

wjp_auhtm17-Jan-10 22:57

17-Jan-10 22:57

The function "IsRunning" will check if the windows service is running.

I think that when creating a windows service just like creating a application, so I do not know how to create it programatically. We must set the windows service before we release it.

Heinzzy18-Jan-10 3:51

Heinzzy

18-Jan-10 3:51

I feel that using a socet connection between service and application is not a good idea because this connection can be terminated by firewall etc
ps use logging instead

wjp_auhtm18-Jan-10 14:21

18-Jan-10 14:21

I.C.
But, just remind once.
I know little about the Logging, I will have some research about that.

Ravi Bhavnani17-Jan-10 9:26

Ravi Bhavnani

17-Jan-10 9:26

A Windows service almost never has access to the desktop. See this[^] article.

/ravi

My new year resolution: 2048 x 1536
Home | Articles | My .NET bits | Freeware
ravib(at)ravib(dot)com

wjp_auhtm17-Jan-10 18:41

17-Jan-10 18:41

Yes, it can not instantiation a win form and show it.
But I think that the socket could connect the win service and win app.

Heinzzy17-Jan-10 5:47

Heinzzy

17-Jan-10 5:47

To capture Keyboard stream use hooks

Read this http://msdn.microsoft.com/en-us/library/ms632589(VS.85).aspx[^]

Simple example

<br />
using System;<br />
using System.Collections.Generic;<br />
using System.Text;<br />
using System.Diagnostics;<br />
using System.Runtime.InteropServices;<br />
<br />
namespace hook<br />
{<br />
    class Program<br />
    {<br />
        private const int WH_KEYBOARD_LL = 13;<br />
        private const int WM_KEYDOWN = 0x0100;<br />
        private static LowLevelKeyboardProc _proc = HookCallback;<br />
        private static IntPtr _hookID = IntPtr.Zero;<br />
<br />
        static void Main()<br />
        {<br />
            _hookID = SetHook(_proc);<br />
            Application.Run();<br />
            UnhookWindowsHookEx(_hookID);<br />
<br />
        }<br />
<br />
        private static IntPtr SetHook(LowLevelKeyboardProc proc)<br />
        {<br />
            using (Process curProcess = Process.GetCurrentProcess())<br />
            using (ProcessModule curModule = curProcess.MainModule)<br />
            {<br />
                return SetWindowsHookEx(WH_KEYBOARD_LL, proc, GetModuleHandle(curModule.ModuleName), 0);<br />
            }<br />
        }<br />
<br />
        private delegate IntPtr LowLevelKeyboardProc(int nCode, IntPtr wParam, IntPtr lParam);<br />
<br />
        private static IntPtr HookCallback(int nCode, IntPtr wParam, IntPtr lParam)<br />
        {<br />
            if ((nCode >= 0) && (wParam == (IntPtr)WM_KEYDOWN))<br />
            {<br />
                int vkCode = Marshal.ReadInt32(lParam);<br />
                if (((Keys)vkCode == Keys.LWin) || ((Keys)vkCode == Keys.RWin))<br />
                {<br />
                    Console.WriteLine("{0} blocked!", (Keys)vkCode);<br />
                    return (IntPtr)1;<br />
                }<br />
            }<br />
            return CallNextHookEx(_hookID, nCode, wParam, lParam);<br />
        }<br />
<br />
        [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]<br />
        private static extern IntPtr SetWindowsHookEx(int idHook, LowLevelKeyboardProc lpfn, IntPtr hMod, uint dwThreadId);<br />
<br />
        [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]<br />
        private static extern bool UnhookWindowsHookEx(IntPtr hhk);<br />
<br />
        [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]<br />
        private static extern IntPtr CallNextHookEx(IntPtr hhk, int nCode, IntPtr wParam, IntPtr lParam);<br />
<br />
        [DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]<br />
        private static extern IntPtr GetModuleHandle(string lpModuleName);<br />
<br />
    <br />
    <br />
    }<br />
}<br />
<br />

michaelgr117-Jan-10 6:40

How to reject changes between two equal DataTables?

17-Jan-10 6:40

how do i use this code? where do i put in? in the program.cs ?
and is it a windows service?

obarahmeh16-Jan-10 21:13

obarahmeh

16-Jan-10 21:13

Dear All,
I have two DataTables. The first (FirstDataTable) is filled by a query and the second is filled by:
SecondDataTable= FirstDataTable;
after this equal operation, the two DataTables are connected and any change is reflected between the both.
I mean when you change the data in the FirstDataTable by a different query, this change will be reflected to the SecondDataTable automatically.
The question here: How can I stop or reject the connection between the two DataTables.
I mean I do not want to reflect the changes after the equal operation. this is to make a copy of the first data returned by the first run of the query.

Regards.

Kind Regards
OBarahmeh

Re: How to reject changes between two equal DataTables?

dan!sh 16-Jan-10 21:20

dan!sh

16-Jan-10 21:20

obarahmeh wrote:
SecondDataTable= FirstDataTable;

This means both tables are referring to the same object in memory. What you can do is, create a deep copy of the FirstDataTable. You can find a lot of examples on web for doing this.

50-50-90 rule: Anytime I have a 50-50 chance of getting something right, there's a 90% probability I'll get it wrong...!!

USB read

michaelgr116-Jan-10 20:39