C# Discussion Boards - CodeProject

Invoking a WMI method on a Remote Machine

bbranded15-Apr-09 6:05

15-Apr-09 6:05

Hello,

I am attempting to invoke the GetVersionVector method of the DfsrReplicatedFolderInfo on a remote machine.

After referring to two articles (1, 2) about the subject on InvokeMethod in C#, I have written the following code:

<br />
string TargetMachine = textBox2.Text;<br />
<br />
<br />
System.Management.ManagementScope oMs = new<br />
<br />
System.Management.ManagementScope("\\\\" + TargetMachine + "\\root\\microsoftdfs");<br />
oMs.Connect();<br />
<br />
System.Management.ObjectQuery oQuery = new System.Management.ObjectQuery("SELECT * FROM DfsrReplicatedFolderInfo"); //WHERE ReplicationGroupName='" + comboBox6.Text + "'");<br />
<br />
ManagementObjectSearcher oSearcher = new<br />
<br />
ManagementObjectSearcher(oMs, oQuery);<br />
<br />
ManagementObjectCollection MgmtObject = oSearcher.Get();<br />
<br />
<br />
foreach (ManagementObject item in MgmtObject)<br />
{<br />
<br />
    //Get an input parameters object for this method<br />
    //ManagementBaseObject inParams = item.GetMethodParameters("GetVersionVector");<br />
<br />
    //Fill in input parameter values<br />
    //inParams["CommandLine"] = "calc.exe";<br />
<br />
    //Execute the method<br />
    ManagementObject outParams = (ManagementObject)item.InvokeMethod("GetVersionVector", null);<br />
<br />
    //Display results<br />
    //Note: The return code of the method is provided in the "returnValue" property of the outParams object<br />
    MessageBox.Show(outParams.ToString());<br />
}<br />

When attempting to InvokeMethod, the following error is thrown:

Object reference not set to an instance of an object.

If I do away with the cast and use declare outParams as an object instead, i get the same error.

Any input is appreciated,

Matt Brown

Re: Invoking a WMI method on a Remote Machine

bbranded15-Apr-09 8:22

bbranded

15-Apr-09 8:22

Here's the solution....

Tweak query as desired...

private void button7_Click(object sender, EventArgs e)
      {

          string TargetMachine = textBox2.Text;



          ManagementPath path = new ManagementPath("\\\\" + TargetMachine + "\\root\\microsoftdfs");

          ManagementScope scope = new ManagementScope(path);

          SelectQuery msQuery = new SelectQuery("SELECT * FROM DfsrReplicatedFolderInfo");

          ManagementObjectSearcher searchProcedure = new ManagementObjectSearcher(scope, msQuery);



          object[] methodArgs = { "" };


          foreach (ManagementObject item in searchProcedure.Get())
          {
              try
              {
                  item.InvokeMethod("GetVersionVector", methodArgs);

                  foreach (string returned in methodArgs)
                  {
                      MessageBox.Show(returned.ToString());
                  }
              }

              catch (SystemException excep)
              {
                  MessageBox.Show(excep.Message);
              }

          }
      }

synchronous and asynchronous communication

yesu prakash15-Apr-09 5:52

yesu prakash

15-Apr-09 5:52

Hi,

what is the diffrent between synchronous and asynchronous communication in socket?
How can i handle many number of client in server using socket. can anybody provide some exaple f asynchronous communication in socket?

thankyou
YPKI

Re: synchronous and asynchronous communication

0x3c015-Apr-09 6:29

0x3c0

15-Apr-09 6:29

Synchronous: The sender will wait for a reply and not do anything else until that reply is sent
Asynchronous: The sender will be notified when a reply is received, and can perform other actions in the background

If you want to handle many different clients, then I'd personally use a collection of Sockets and hook them all up to the same event. In the event, look up the sender parameter to find out who sent what

Re: synchronous and asynchronous communication

yesu prakash15-Apr-09 18:08

yesu prakash

15-Apr-09 18:08

can you please explain little more about handling multiple clients?
In my program each clients have numbet of functionalities like text chat,image sharing, presentation etc... all are handled using a listening port.. i feared that will all make the program struck or inefficient
How will be if number of port open for handle clients?

Thankyou
YPKI

Problem in disabling close button(X) of window.

priyamtheone15-Apr-09 5:25

priyamtheone

15-Apr-09 5:25

Hi,
I am trying to work on an application that disables the close button (X) on the upper right hand corner of a window. In order to do that I need to use calls to API methods like GetSystemMenu, EnableMenuItem and RemoveMenu. I can figure out how these methods work but there are certain parameters that these methods have whose values that need to be passed to them as argument is unknown to me. How can I know them.

E.G.- for EnableMenuItem, the parameters are- hMenu (handle to the menu), uIDEnableItem (The menu item to be enabled, disabled, or grayed), uEnable (This parameter must be a combination of at least two of the following:
MF_BYCOMMAND or MF_BYPOSITION
MF_ENABLED, MF_DISABLED, or MF_GRAYED)

Now when I call this method from my application I supply the current window handle as the first argument, the item no. to be disabled/enabled as the second argument but I CAN'T UNDERSTAND WHAT TO SEND AS THE THIRD ARGUMENT. What exactly are the possible values for those parameters- MF_BYCOMMAND or MF_DISABLED. I checked certain examples where they are supplying hexadecimal values like &HF060, &H1, 0x400, 0x1000, 0x2 etc. or integer values like 1024, 2 etc. But how would I know what exactly these values are and when to use which value. The same problem arises in case of calling RemoveMenu method. If you know about any chart or tutorial that lists the values of these parameters then plz refer. Waiting for your help. Thanks.

Re: Problem in disabling close button(X) of window. [modified]

DaveyM6915-Apr-09 5:31

DaveyM69

15-Apr-09 5:31

These are all listed in the winuser.h (header file). Depending on the installation on your system you may already have it. If not, Google for that and you'll find loads of references.

Dave
BTW, in software, hope and pray is not a viable strategy. (Luc Pattyn)
Visual Basic is not used by normal people so we're not covering it here. (Uncyclopedia)
Why are you using VB6? Do you hate yourself? (Christian Graus)

modified on Wednesday, April 15, 2009 11:38 AM

Re: Problem in disabling close button(X) of window.

agent00zelda15-Apr-09 5:32

agent00zelda

15-Apr-09 5:32

Looks like they are constants, found this site which describes them and how to use them, hope it helps...

http://msdn.microsoft.com/en-us/library/aa929762.aspx[^]

Re: Problem in disabling close button(X) of window.

priyamtheone15-Apr-09 20:16

priyamtheone

15-Apr-09 20:16

Well I have checked the site but they are just describing the parameters there. But I want to know what exactly are the values that can be supplied as arguments to those parameters. If you see the following links u'll see they are using some hexadecimal values as arguments:

http://www.codeproject.com/script/Forums/View.aspx?fid=1649&select=2436995&tid=2436667[^]

http://www.codeproject.com/script/Forums/View.aspx?fid=1649&select=1754349&tid=1749113[^]

That's what I want to know. Hope I make that clear to you. Thanks.

Re: Problem in disabling close button(X) of window.

Luc 64801115-Apr-09 5:40

Luc 648011

15-Apr-09 5:40

If you want the close box to be visible but inoperative (a silly idea if you ask me), then use the FormClosing event and set e.Cancel true. No native code needed whatsoever.

Smile | :)

Re: Problem in disabling close button(X) of window.

DaveyM6915-Apr-09 5:43

DaveyM69

15-Apr-09 5:43

I used this functionality in an unrelated article[^]. It may be worth looking at the source.

Re: Problem in disabling close button(X) of window.

PIEBALDconsult15-Apr-09 6:03

PIEBALDconsult

15-Apr-09 6:03

Several people have asked this sort of thing (even in this forum), a quick search of the messages will find the answer:

http://www.codeproject.com/script/Forums/View.aspx?fid=1649&select=2436995&tid=2436667[^]

http://www.codeproject.com/script/Forums/View.aspx?fid=1649&select=1754349&tid=1749113[^]

Re: Problem in disabling close button(X) of window.

priyamtheone15-Apr-09 21:25

priyamtheone

15-Apr-09 21:25

Well friends I found a solution. Checkout this link:
http://www.pinvoke.net/default.aspx/user32.EnableMenuItem[^]

SIteMap

kibromg15-Apr-09 4:02

kibromg

15-Apr-09 4:02

Hi Guys,

I would like to create Multiple parent node on may Page where the First Node is independent of the other Node.

Home
page1
page2
Services
page3
page4
Contact
page5
Page6

etc...

How can i create webconfig.sitemap file to have the above structure on a page?

Home service and Contact should be independent links not embebed under Home.

Many thanks

Re: SIteMap

hat_master15-Apr-09 6:04

hat_master

15-Apr-09 6:04

Try something like this:

<siteMap>
   <siteMapNode title="Home" url="default.aspx">
      <siteMapNode title="Page1" url="page1.aspx" />
      <siteMapNode title="Page2" url="page2.aspx" />
   </siteMapNode>
   <siteMapNode title="Services" url="services.aspx">
      <siteMapNode title="Page3" url="page3.aspx" />
      <siteMapNode title="Page4" url="page4.aspx" />
   </siteMapNode>
   <siteMapNode title="Contact" url="contact.aspx">
      <siteMapNode title="Page5" url="page5.aspx" />
      <siteMapNode title="Page6" url="page6.aspx" />
   </siteMapNode>
</siteMap>

You can add links to any node by placing them in between <siteMapNode></siteMapNode>. Those links will not be present or visible in your menu until you clink on the parent link. See how that works for you.

Josh

Re: SIteMap

kibromg15-Apr-09 6:36

kibromg

15-Apr-09 6:36

Many thanks.Its really much appreciated.

What i want is to have multiple parent link.So when you click on Home to will not hide service Link.

when you implement like you mentioned it comes with an error.

"Exactly one element is required directly inside the element".

Please advice.

Many thanks

Re: SIteMap

hat_master15-Apr-09 7:18

hat_master

15-Apr-09 7:18

That's what I get for trying to go from memory! You have to wrap everything in one <siteMapNode></siteMapNode> element. If you are using this with a SiteMapDatasource, you can change the ShowStartingNode property to false if necessary.

<siteMap>
   <siteMapNode>
      <siteMapNode title="Home" url="default.aspx">
         <siteMapNode title="Page1" url="page1.aspx" />
         <siteMapNode title="Page2" url="page2.aspx" />
      </siteMapNode>
      <siteMapNode title="Services" url="services.aspx">
         <siteMapNode title="Page3" url="page3.aspx" />
         <siteMapNode title="Page4" url="page4.aspx" />
      </siteMapNode>
      <siteMapNode title="Contact" url="contact.aspx">
         <siteMapNode title="Page5" url="page5.aspx" />
         <siteMapNode title="Page6" url="page6.aspx" />
      </siteMapNode>
   </siteMapNode>
</siteMap>

Re: SIteMap

kibromg16-Apr-09 0:54

kibromg

16-Apr-09 0:54

Many thanks.It works very well Now.

Thanks

Stopping a Windows Service in a Timely Manner...

agent00zelda15-Apr-09 3:42

agent00zelda

15-Apr-09 3:42

Hello! I recently started writing my first Windows Service project in C#, and I'm at a point now where I have a lot of time to perfect things before I continue.

I was wondering what's considered generally "good practice" with regards to Windows Services. Specifically, the stopping mechanism.

When my service starts, it kicks off a few threads that perform some file manipulation. When the service stops, I want it to shut those threads down gracefully. Ideally, shutting down the service puts the file system in a state where the manipulation can be easily resumed upon restarting the service. So, when shutting down the service, I'd prefer to let one of the threads (if it's currently doing work) finish the works it's already started, but in some cases, this can take several minutes.

Is this considered bad practice, or is this something I shouldn't really be concerned with? Are there other things anyone thinks I should consider?

Re: Stopping a Windows Service in a Timely Manner...

PIEBALDconsult15-Apr-09 6:15

PIEBALDconsult

15-Apr-09 6:15

It sounds OK to me, though "several minutes" sounds excessive. Is there a way to have them stop after the current operation even though there are still other things to do?

agent00zelda wrote:
it kicks off a few threads that perform some file manipulation

Can those be in their own Services?

Re: Stopping a Windows Service in a Timely Manner...

agent00zelda15-Apr-09 7:38

agent00zelda

15-Apr-09 7:38

Thank you for your response!!

PIEBALDconsult wrote:
Can those be in their own Services?

Actually, yes, and they are.. I guess I should have mentioned that part Smile | :)

The way I had it implemented before I made the initial post was I pretty much let it finish everything until it was able to submit the data to the other services. But Windows spazzed out because it couldn't stop the main service until it finished the preceding operations.

What I ended up doing was defining like a project "state" DataTable that could be exported and imported again when the service restarts. Your suggestion was well-taken -- pretty much made the current operation finish and then updated the project state based on that. I don't know if using a DataTable is the best approach, but it seems to work much better, since it takes considerably less time to stop the service.

Still open to suggestions if you or anyone can think of a better approach, though!! I guess I'm in a C# experimentation phase Smile | :)

Need a clue with Configuration Sections

Optimus Chaos15-Apr-09 3:28

Optimus Chaos

15-Apr-09 3:28

Hi folks,

I could please need some help with custom Configuration Sections:

Let me first describe what I want to acheive:
I want to have a Configuration section which consists of several items (I already managed that, it's working fine)
Now each of these items can should have another list of subsitems.
The resulting config file should look like this:

+ section
- parentitem
- childitem
- childitem
...
- parentitem
- childitem
...

As I said I already managed add the section and create the "parent items".
Now I tried using a ConfigurationElementCollection derived class for the collection of
"childitems" but they won't show up.

Does anyone have an idea how I can acheive my goal?

Many thanks in advance.

Stefan

overload operator +

al3xutzu0015-Apr-09 2:16

al3xutzu00

15-Apr-09 2:16

Hi guys,
Quick question:
I got this class:

public class PresaHidraulica<br />
   {

.....
public System.Collections.ArrayList listaRevizii;
}

and i want to overload the operator + to add an object of another class(Revizie) in this ArrayList from this class.
I tried :

public static PresaHidraulica operator +(Revizie r1)<br />
{<br />
}

And i get the error : The parameter of a unary operator must be the containing type

Any suggestions please?

Regards,
Alex

“Be the change you want to see in the world.”

Re: overload operator +

Dino Mulahusic15-Apr-09 2:25

Dino Mulahusic

15-Apr-09 2:25

That means that your parameter r1 is of wrong type: Revizie.
When you overload operator + you must pass in parameter PresaHidraulica

public static PresaHidraulica operator +(PresaHidraulica ph)
{
}

Maybe you should create a method called AddRevizie

public void AddRevizie(Revizie r1)
{
    listaRevizii.Add(r1);
}

Re: overload operator +

0x3c015-Apr-09 2:28

0x3c0

15-Apr-09 2:28

The first parameter must be the containing type. In this instance, you should change the operator method signature to public static PresaHidraulica operator +(PresaHidraulica self, Revizie r1)

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