C# Discussion Boards - CodeProject

Re: Installer Dilemma!! [modified]

Willem_Le_Roux1-Aug-06 0:45

Willem_Le_Roux

1-Aug-06 0:45

Okay

And now repeat in English please Laugh | :laugh:

Sorry mrCondor, but I have no idea what you are talking about... Yet. I played around with what I think your idea is, and it seems that I will have to write some other application (exe), DLL, script (js... preferably) or something like that to get the information and write it to the registry... somewhere... Perhaps?

Also, I toyed around in MS help and got some interesting goodies about Properties, USERNAME properties, COPANYNAME properties, UserSID properties, how all this gets written to the registry under the "InstallProperties" key and all sorts of tit-bits like that, but no example, no nothing. Frown | :(

Can anybody please steer me in a general direction? I have absolutly no idea where to start... Fooling a little feelish now! Unsure | :~

uhm he he he...

Willem Le Roux

Singleton object doesn't detroy when i assign it to null.

madhusri31-Jul-06 2:07

madhusri

31-Jul-06 2:07

Here is the code sample of sington class and their clients

<br />
public class single<br />
    {<br />
        public string str = "Hello";<br />
        private static single s = null;<br />
<br />
        private single()<br />
        {<br />
        }<br />
<br />
        public static single CreateInstance()<br />
        {<br />
            if (s == null)<br />
                s = new single();<br />
<br />
            return s;<br />
        }<br />
<br />
        public string Get()<br />
        {<br />
            return str;<br />
        }<br />
    }<br />
    class Program<br />
    {<br />
        static void Main(string[] args)<br />
        {<br />
            single i = single.CreateInstance();<br />
<br />
            string str1 = i.Get();<br />
            Console.WriteLine(str1);<br />
<br />
            i.str = "World";<br />
<br />
            i = null;<br />
            single j = single.CreateInstance();<br />
<br />
            string str2 = j.Get();<br />
            Console.WriteLine(str2);<br />
<br />
            j = single.CreateInstance();<br />
            j.str = "New";<br />
            string str3 = j.Get();<br />
            Console.WriteLine(str3);<br />
<br />
            <br />
        }<br />
    }<br />

Output::
Hello
World
New

But it should be
Hello
Hello
New

since we assigned i=null then the singleton must be destroyed and new instance should be created when j = single.CreateInstance(); executed right?

Thanks and Regards
Madhu

Re: Singleton object doesn't detroy when i assign it to null.

Ravi Bhavnani31-Jul-06 2:19

Ravi Bhavnani

31-Jul-06 2:19

No, since i is a local variable. You're just nulling your local reference of the singleton (which continues to exist).

/ravi

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Re: Singleton object doesn't detroy when i assign it to null.

leppie31-Jul-06 3:23

leppie

31-Jul-06 3:23

madhusri wrote:
since we assigned i=null then the singleton must be destroyed and new instance should be created when j = single.CreateInstance(); executed right?

No, that defeats the goal of the singleton pattern.

xacc.ide-0.2.0.50 - now with partial MSBuild support!

Re: Singleton object doesn't detroy when i assign it to null.

madhusri31-Jul-06 5:35

madhusri

31-Jul-06 5:35

Hi leppie,

When i = null is assigned, there are no reference pointers pointing to the singleton object. Hence if there is a GC, then the singleton object has to be deleted. In this case, next time an instance to the singleton object is created, it should be a new object again. But the old object is being retained and returned when i call createInstance() again.

Basically, when will the singleton object be destroyed from memory?

We understand that an object will be deleted if there are no references to that object or if the object is set to null. Is this right?

Thanks and Regards
Madhu

Not necessarily

Ennis Ray Lynch, Jr.31-Jul-06 7:42

Ennis Ray Lynch, Jr.

31-Jul-06 7:42

When all object references are removed it is scheduled for garbage collection. The first round of the GC does the clean up. The next time the GC runs it removes it. If you need to free resources implement the IDisposable method and call that before assigning null and then just don't worry about it.

A man said to the universe:
"Sir I exist!"
"However," replied the Universe, "The fact has not created in me A sense of obligation."

-- Stephen Crane

Re: Not necessarily

engsrini31-Jul-06 8:15

engsrini

31-Jul-06 8:15

Event we tried to GC the i object after assigning to null ie.

i=null;
GC.Collect();
Thread.Sleep(2000);// Waitin for some time to Collect the object i by GC

even this never destroyed the object.

The GC has to run twice

Ennis Ray Lynch, Jr.31-Jul-06 8:37

Ennis Ray Lynch, Jr.

31-Jul-06 8:37

And if custom memory management is so important you shouldn't be using C#.

A man said to the universe:
"Sir I exist!"
"However," replied the Universe, "The fact has not created in me A sense of obligation."

-- Stephen Crane

Re: Singleton object doesn't detroy when i assign it to null.

Colin Angus Mackay31-Jul-06 8:01

Colin Angus Mackay

31-Jul-06 8:01

madhusri wrote:
When i = null is assigned, there are no reference pointers pointing to the singleton object.

This is incorrect. The class you showed has a static reference to its one and only instance.

madhusri wrote:
But the old object is being retained and returned when i call createInstance() again.

And it manages this because something is holding a reference that the CreateInstance() method can pass back.

madhusri wrote:
We understand that an object will be deleted if there are no references to that object or if the object is set to null. Is this right?

The first part is correct. The second part is incorrect because you are not setting the object to null, not now, not ever. What you are doing is setting a reference to the object to null.

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Re: Singleton object doesn't detroy when i assign it to null.

engsrini31-Jul-06 8:23

engsrini

31-Jul-06 8:23

Now we understand. Out situation is like One exe will invoke function in 2 separate dlls using reflection. first exe loaded the dlls. those dlls create log object using CreateInstance(). suppose if the dll1 assigned the

logobject.Moudulename="First";  //Variable in log object <br />
logobject=null;<br />
GC.Collect();

then the exe unloaded this dll1 and try to access dll2 function which uses logobject instance, will the changes made by dll1 will be afected to dll2's Logobject? if yes means the logobjected is collected by GC right so it will be no longer available to dll2 rite?

Re: Singleton object doesn't detroy when i assign it to null.

V.31-Jul-06 4:10

31-Jul-06 4:10

I think you need to dispose the object out of memory.
Assigning null is no different then assigning a value. The object itself still exists.

I've found a living worth working for, but I haven't found work worth living for.

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Re: Singleton object doesn't detroy when i assign it to null.

Colin Angus Mackay31-Jul-06 5:15

Colin Angus Mackay

31-Jul-06 5:15

madhusri wrote:
since we assigned i=null then the singleton must be destroyed and new instance should be created when j = single.CreateInstance(); executed right?

Nope, wrong!

See this code from CreateInstance:

if (s == null)
s = new single();
return s;

What happens here is the one and only ever instance never to be repeated is created if it does not exist and stored in the static field called s. s is always returned. Nothing else ever assigns to s therefore the singleton pattern is maintained becuase you have ensured that there will only ever be one and only one ever instance of the object. This is the goal of the singleton, the behaviour you expect is at odds with the pattern you have chosen.

Ctrl + B in RichtextBox

AB777131-Jul-06 2:02

AB7771

31-Jul-06 2:02

I want to set the font style to Bold when the user clicks Control + B key combination,
How do i do that?

Thanks & Regards,
Pramod

Re: Ctrl + B in RichtextBox

stancrm31-Jul-06 2:16

stancrm

31-Jul-06 2:16

private void richTextBox1_KeyDown(object sender, System.Windows.Forms.KeyEventArgs e)
{
	if(e.KeyCode == Keys.B && e.Modifiers == Keys.Control)
	{
		this.richTextBox1.SelectionFont = new Font("Microsoft Sans Serif", 8, FontStyle.Bold);
	}
}

Re: Ctrl + B in RichtextBox

AB777131-Jul-06 2:24

AB7771

31-Jul-06 2:24

Thanks

Re: Ctrl + B in RichtextBox

Empires31-Jul-06 2:28

Empires

31-Jul-06 2:28

You could also maintain the font and do it like this:

if (e.KeyCode == Keys.B && e.Control)
{
richTextBox1.SelectionFont = new Font(
richTextBox1.SelectionFont,
richTextBox1.SelectionFont.Style ^ FontStyle.Bold
);

e.Handled = true;
}

Michael Francik
Empireland, Inc.

Re: Ctrl + B in RichtextBox

AB777131-Jul-06 2:59

AB7771

31-Jul-06 2:59

Everything is fine
but when i press Ctrl + I the cursor moves one tab ahead,
Why does this happen?
is Ctrl + I any pre-defined short cut for richtextbox.
i am working in VS 2005.

Thanks,
Pramod

Re: Ctrl + B in RichtextBox

AB777131-Jul-06 2:37

AB7771

31-Jul-06 2:37

Thanks for that can also tell me how can i insert a link to a Folder in a richtext box.

Pramod

Re: Ctrl + B in RichtextBox

stancrm31-Jul-06 3:27

stancrm

31-Jul-06 3:27

See this:
http://msdn2.microsoft.com/en-us/library/f591a55w.aspx

Re: Ctrl + B in RichtextBox

AB777131-Jul-06 3:31

AB7771

31-Jul-06 3:31

i tried but when i set a link as http://microsoft.com the text display should be only microsoft.com , but the text displayed is http://microsoft.com

please suggest Any other way to solve this.

Thanks,
Pramod

Re: Ctrl + B in RichtextBox

stancrm31-Jul-06 3:36

stancrm

31-Jul-06 3:36

For example, if you want to open Directory c:\ then use
file:\\c:\

or if you want to open d:\temp then use
file:\\d:\temp

Controlling Access to network (File/Directory)

sundar15631-Jul-06 1:51

sundar156

31-Jul-06 1:51

Hi,
How do i control access to a directory or file in a network programatically .Im using .Net Framework 1.1

(I have to restrict access to network for a particular user programatically)

Thanks in advance,

Luck is Opportunity with hardwork

Re: Controlling Access to network (File/Directory)

LongRange.Shooter31-Jul-06 5:25

LongRange.Shooter

31-Jul-06 5:25

Anything you do programmatically is in the context of the user that is running your program. If you want to kill access for a user, you cannot change a directory access while 'being' that user.

The only way is with network security setting the access rights on the folder. That's why we have network administrators in the world.

Re: Controlling Access to network (File/Directory)

sundar15631-Jul-06 8:27

sundar156

31-Jul-06 8:27

Thanks for your comments..

But is it possible to watch a directory for any changes,like we have FileSystemWatcher for files.

(or)

Is it possible to raise an Event if a shared directory is being accessed in windows.

I am using .Net Framework 1.1

Thanks in advance..

Luck is Opportunity with hardwork

Developing a .NET client to copy files from a sharepoint portal server

Nishanth Nair31-Jul-06 1:35

Nishanth Nair

31-Jul-06 1:35

Hi,
I need to develop a .NET application in C# that will run in a client machine.
This application should connect to a sharepoint server running in another machine, authenticate using username and password, and copy specified files from the sharepoint portal server.
I tried to use Microsoft.Sharepoint dll in the client side code, but the following error was occurring "But when I run the Application it says that the COM component is not registered or unavailable" . i feel the dll should be used only in the sharepoint server machine only.

Could someone help me in how to go about doing this.. if possible, some code snippetts will be of great help.
Thanks
Nishanth

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