Singletons.. - C# Discussion Boards

Re: combobox question ? [modified]

microsoc22-May-06 23:53

microsoc

22-May-06 23:53

hi Mehmet Fatih Akbulut! Smile | :)

maybe this is what your looking for...

the FindString[^] and FindStringExact[^] methods of the combobox. Smile | :)

hope this helps! Smile | :)

microsoc

how can i add a bitmap to resource directory project by code?

Sasuko22-May-06 2:47

Sasuko

22-May-06 2:47

How can i add a bitmap into resource folder of the solution by code in design mode? (No right click on the folder... but automatically by code)

Re: how can i add a bitmap to resource directory project by code?

stancrm22-May-06 21:14

stancrm

22-May-06 21:14

See this one : http://msdn2.microsoft.com/en-us/system.resources.resourcewriter.aspx

Installation Script [modified]

mfc_surfer22-May-06 2:45

mfc_surfer

22-May-06 2:45

Hello,
I'm creating a setup project for my application. I need to ask user to specify a directory during installation, which I have to set a registry key value to that directory. I've done this for installation directory but I don't know how to ask user to specify another directory as well and how to set the registery accordingly.

Any idea would be appreciated.

Thanks & Regards
P.S. I'm using wisual C# .NET

-- modified at 8:46 Monday 22nd May, 2006

Re: Installation Script [modified]

Nimit Patel22-May-06 3:30

Nimit Patel

22-May-06 3:30

Hi,

You can add one form in user interface where user can select the path of the folder and that path will be referenced in the coding for writting the registery.

Nimit Patel

C# : implement chat room in pocket pc

Pentellcc22-May-06 2:31

Pentellcc

22-May-06 2:31

I wish to implement a chat room that use between PDA (pocket pc) and desktop pc using C#. Is it any idea to implement this? XML web service can implement this? or any other suggestion for it?

The chat room that I plan to implement is one to one conversation only. Besides, if one of them already started the conversation, other people can't make conversation with him unless he had closed the conversation. Is it possible implement in xml web service? How could xml web service checking the status of the person to see them in conversation or not?

Do pocket pc support foreign language?

Pentellcc22-May-06 2:24

Pentellcc

22-May-06 2:24

I wish to implement a application to make translation between chinese word to english word in pocket pc. It will allow user write the chinese word in pocket pc then send remotely by .net compact framework(xml web service) to the remote server. Is the pocket pc itself support write foreign language (chinese word) and can xml web service send chinese word to the remote server from pocket pc?

Singletons..

martin_hughes22-May-06 2:20

martin_hughes

22-May-06 2:20

Hey all,

I'm sure this is a no-brainer for most of you, but it's something I never learned about in the old procedural days, so any help appreciated.

I keep reading about the Singleton, and looking at the implementations, folks talk about thread safety etc. etc., such as in this article: http://www.yoda.arachsys.com/csharp/singleton.html.

However, I was under the impression that if a class was declared as public static it would have application scope, but couldn't be instantiated, and so would only exist once within an application... so any methods or properties you put in a static class will also only have one instance.

I must be missing the point here somewhere - one conclusion I've come to is that you infact wrap another object, that would normally be instantiable, within a singleton class, in effect making the wrapped object a Singleton as well... is this the case?

Re: Singletons.. [modified]

J4amieC22-May-06 2:55

J4amieC

22-May-06 2:55

Its important to get one distiction solid in your mind.

A singleton is a single instance of a clas.

So, you should write whatever class will be a singleton in the normal manner before starting. ie/

public class MySingleton
{
   private string someVar = "";

   private MySingleton()
   {
   }

   public string SomeVar
   {
     get{ return this.someVar; }
     set{ this.someVar = value; }
   }
}

Note this has instance variables/accessors. The other thing to note is that it has a private constructor only!! This stops new instances of being created for this object (except for within the code).

Now, the purpose of a singleton. If, for whatever reason makes sense for your application, there should only EVER be one instance of MySingleton it is a candidate for the Singleton pattern.

1 line change

public class MySingleton
{
   public static readonly MySingleton Current = new MySingleton();

   private string someVar = "";

   private MySingleton()
   {
   }

   public string SomeVar
   {
     get{ return this.someVar; }
     set{ this.someVar = value; }
   }
}

Now, in your app you could have:
MySingleton.Current.MyVar = "Hellow World";

For examples of Singleton use within the framework look at HttpContext.Current in the System.Web namespace.

Current blacklist
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-- modified at 8:56 Monday 22nd May, 2006

Re: Singletons.. [modified]

martin_hughes22-May-06 8:55

martin_hughes

22-May-06 8:55

Many thanks for that - I think I'm getting it! *Goes off to do some experimentation in code*

exception

Smitha Sondur22-May-06 2:14

Smitha Sondur

22-May-06 2:14

Hi,

When I tried to retrieve the contacts from palm desktop software using c#.net application I got the following Exception:
"Retrieving COM class factory for component with CLSID(22C48232-4BC5-11D4-80FB-00C04FA03755"
Please help me.

Thanks,
Smitha Sondur

Smitha Sondur

a few important questions about forms ? help please ...

cmpeng3422-May-06 2:03

cmpeng34

22-May-06 2:03

hi all,
first: i have a tabcontrol page and it contains a few textbox and 3 buttons (insert, cansel, close).
i tried to arrange taborder for this page but interestingly Insert button has a precedence according to textboxes although i selected textboxes to have taborder first ;(
its weird. is there something wrong with my form ? or do i miss something ?
my taborder (did in this order) : pagetabs > textboxes > buttons (insert, cansel, close)
but form's tab order : pagetabs > insert button > textboxes > the other 2 buttons.

second: for cansel button i just initialize textbox(n).Text=""; what should i do to make comboboxes to show nothing ? combobox(n).Text=""; doesnt work Frown | :(

i dont want to add or remove something from comboboxes. just want not to show any item inside.

third: i use tooltip to give some info about for pagetabs. but if i open another tab then move back to the previously opened tab. tooltip doesnt show anythin any more ;(
how do i edit tooltip properties so as to enable it to show infos continuously even i browse in tabpages ?

thanks in advance.
bye.

Re: a few important questions about forms ? help please ...

Dustin Metzgar22-May-06 5:46

Dustin Metzgar

22-May-06 5:46

1. The tab order will work fine, but you should try taking the control that you want the user to be on first and calling Focus() on it. You can listen for the event when the user switches tabs and do it there, or when the tab pane becomes visible.

2. You can use the Text property with a combobox. What is your DropDownStyle set to? If the combobox requires that a list item be picked, then it's not going to let you clear out your text.

3. Are you using the SetToolTip method? Is the container your form or the tab pane? Have you tried listening for the tab switch event and resetting your tooltips?

www.logifusion.com

Find Button

alwz_nikhil22-May-06 1:43

alwz_nikhil

22-May-06 1:43

Hi..
I have some text text in RichTextBox ..And i want to search for some text.
If that text appears more than one time it should select all that occurances.
Is it possible to do that?

Wat im using curently is as follows..
int startindex = 0;
int tmp = rtxbox.Text.ToUpper().IndexOf(txtFind.Text.ToUpper());

if (tmp > -1 && rtxbox.Text.Length > 0)
{
startindex = tmp;
rtxbox.Find(txtFind.Text);
rtxbox.rtxbox.ScrollToCaret();
}

this only selects the first occurance of that text..
help me out

Re: Find Button

CodyGen22-May-06 4:44

CodyGen

22-May-06 4:44

You might try checking this out: http://www.dotnetjunkies.com/Tutorial/195E323C-78F3-4884-A5AA-3A1081AC3B35.dcik[^]

printing unicode characters on Console [modified]

cshivaprasad22-May-06 1:43

cshivaprasad

22-May-06 1:43

I have a string variable which contain UniCode string as its value.
when i am printing it on console with writeline method, it showing "?" on the screen instead of original string.
can any one tell me, how can resolve problem.

Bugs Never Die

-- modified at 8:19 Monday 22nd May, 2006

Re: printing unicode characters on Console [modified]

stancrm22-May-06 3:53

stancrm

22-May-06 3:53

You can convert it to ASCII :

Encoding srcEncoding = Encoding.Unicode;
Encoding tgtEncoding = Encoding.ASCII;
byte[] byteInUnicode = Encoding.Unicode.GetBytes("your string");
byte[] byteInAscii = System.Text.Encoding.Convert(srcEncoding, tgtEncoding, byteInUnicode);	
string strInAscii = Encoding.ASCII.GetBytes(byteInAscii);

FileStream in c#

H he el el oooo22-May-06 1:26

H he el el oooo

22-May-06 1:26

FileStream xsdStream = new FileStream(@".\XMLSchema\AuthenticateUser.xsd", FileMode.Open);
this line is not getting executed when i try to run this using virtual directory. why it is so

ItsMe

Re: FileStream in c#

Colin Angus Mackay22-May-06 1:46

Colin Angus Mackay

22-May-06 1:46

What do you mean by "not getting executed"? Is there an error? What is the exception message? Is it doing nothing at all?

"On two occasions, I have been asked [by members of Parliament], 'Pray, Mr. Babbage, if you put into the machine wrong figures, will the right answers come out?' I am not able to rightly apprehend the kind of confusion of ideas that could provoke such a question."
--Charles Babbage (1791-1871)
My: Website | Blog

Datagridview from 2 tables

nikitaj22-May-06 1:08

nikitaj

22-May-06 1:08

Hi,

I'm having a situation like this.

I am using a datagridview which fills up Item details from a table, say Items.

I am also adding a Datagridcomboboxcolumn to this datagrid whose datasource is table 'Category' from where it should show various category names in combo box for user to select one.

I can see the datagridview being filled up with data from Items table.I can also see the combo box column being generated for each row.However, the combobox doesnot work and show any values from its datasource.

How can I show rows from one table and combo box in each row from other table in a datagridviw ?

here is the pseudocode :

DataTable dt = objItems.GetItems(); // gives Item details in a table.

DataTable dtCat = objCat.GetCategory(); // returns category details in form of a table.

dgItems.DataSource = dt; // dgItems is a datagridview created with the help of toolbox on a winform.

DataGridViewComboBoxColumn comboColumn = new DataGridViewComboBoxColumn();

comboColumn.DataPropertyName = "CategoryDesc";

comboColumn.HeaderText = "Select Category";

comboColumn.MaxDropDownItems = 5;

comboColumn.DataSource = dtCat;

comboColumn.ValueMember = "CategoryId";

comboColumn.DisplayMember = "CategoryDesc";

dgItems.Columns.Insert(dt.Coulmns.Count + 1, comboColumn);

Thanks in advance.

Nikita

C#.net

abhaygalande22-May-06 0:32

abhaygalande

22-May-06 0:32

i want code for simple search and advance search Sleepy | :zzz: