C# Discussion Boards - CodeProject

Dave Kreskowiak29-Jul-05 4:26

29-Jul-05 4:26

Isn't it also astounding how many people don't know how to use the Internet, or more specifically, a search engine?

RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome

Re: Technical help

Christian Graus31-Jul-05 13:18

Christian Graus

31-Jul-05 13:18

Yeah, that's also a good point.

Christian Graus - Microsoft MVP - C++

Re: Technical help

leppie28-Jul-05 23:28

leppie

28-Jul-05 23:28

Christian Graus wrote:
I'm astounded how many people use the .NET framework and have absolutely no idea how it works.

I agree, it's shocking! I wonder how people even manage to write code not knowing the basics.

^{xacc-ide 0.0.15 now with C#, MSIL, C, XML, ASP.NET, Nemerle, MyXaml and HLSL coloring - Screenshots}

synchronized arrayList in C#

ppp00128-Jul-05 15:51

ppp001

28-Jul-05 15:51

Hi,

what is the most proper right to create a synchronized arrayList
that can allow different threads to access it ?

Thanks

Re: synchronized arrayList in C#

Lars Niedziolka28-Jul-05 16:18

Lars Niedziolka

28-Jul-05 16:18

Hi Swakswi,

Use

ArrayList mySyncArrayList = ArrayList.Synchronized(myArrayList);

See
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpref/html/frlrfsystemcollectionsarraylistclasssynchronizedtopic.asp

XmlTextReader - reading from a string?

andrewpritchie28-Jul-05 14:18

andrewpritchie

28-Jul-05 14:18

All,

Just wondering if it is possible to parse XML from a string in memory, as opposed to a file? I'm getting XML data over a TCP/IP connection, and it is read into a string in memory. I could dump the string to a file, then parse the filename to XmlTextReader, but that seems like a waste of resources.

Any pointers would be appreciated.

Cheers,
Andrew

Re: XmlTextReader - reading from a string?

Lars Niedziolka28-Jul-05 15:24

Lars Niedziolka

28-Jul-05 15:24

Hi Andrew,

there are some solutions:

1st)
If you only want an XmlDocument, use the methode LoadXml of the XmlDocument class.

<br />
string myXmlContent = @"<GoodSides><Side name='CodeProject'>http://www.codeproject.com</Side></GoodSides>";<br />
XmlDocument xmlDoc = new XmlDocument();<br />
xmlDoc.LoadXml(myXmlContent);<br />

2nd)
Copy the bytes (or strings) to a MemoryStream.

<br />
byte[] myContent = ...;<br />
MemoryStream memStream = new MemoryStream(myContent);<br />
XmlTextReader xmlReader = new XmlTextReader(memStream);<br />

<br />
MemoryStream memStream = new MemoryStream();<br />
StreamWriter memWriter = new StreamWriter(memStream);<br />
memWriter.Write(@"<GoodSides>");<br />
memWriter.Write(@"<Side name='CodeProject'>http://www.codeproject.com</Side>");<br />
memWriter.Write(@"</GoodSides>");<br />
memStream.Position = 0; // Reset the position<br />
XmlTextReader xmlReader = new XmlTextReader(memStream);<br />

3rd)
Implement a own class with Stream as BaseClass.
This class can read the datas direct from TCP/IP.

<br />
class MyOwnStream: Stream<br />
{<br />
  // especialy<br />
  int Read(byte[] buffer, int offset, int count)<br />
  {<br />
    ...<br />
  }<br />
};<br />
MyOwnStream myStream = new MyOwnStream(...);<br />
XmlTextReader xmlReader = new XmlTextReader(myStream);<br />

4th)
Use the SocketStream direct. (If the stream contains only the xml data and no more.)

<br />
NetworkStream myNetworkStream = new NetworkStream(mySocket);<br />
XmlTextReader xmlReader = new XmlTextReader(myStream);<br />

Hope, it helps
Niedzi

How can I...

KORCARI28-Jul-05 12:23

KORCARI

28-Jul-05 12:23

how can I get message I want in a textbox after checking a chekbox?

Re: How can I...

Libor Tinka28-Jul-05 12:39

Libor Tinka

28-Jul-05 12:39

Use CheckBox.CheckedChanged event:

checkBox1.CheckedChanged += new EventHandler(CheckBoxOnCheckedChanged);

And then implement this handler:

void CheckBoxOnCheckedChanged(object obj, EventArgs ea) {

textBox.Text = message;

textBox.Invalidate(); // you shouldn't use this line, but...
}

Algorithm for creating a list from a hierarchy?

Judah Gabriel Himango28-Jul-05 12:17

Judah Gabriel Himango

28-Jul-05 12:17

I have a hierarchy of objects. For simplicity's sake, let's say I have a TreeView containing a hierarchy of TreeNodes.

I'd like to add these TreeNodes to an ArrayList, with the top-most level TreeNodes being added at the beginning of the list, 2nd-level TreeNodes added next, 3rd level nodes after that, and so on.

Anyone know of an efficient algorithm to do this? Or should I just resort to manually going down each hierarchy level, adding each node to the list as I go along?

Tech, life, family, faith: Give me a visit.
I'm currently blogging about: Homosexuality in Christianity
Judah Himango

Re: Algorithm for creating a list from a hierarchy?

Libor Tinka28-Jul-05 12:35

Libor Tinka

28-Jul-05 12:35

This is not a depth-first tree traversal, so you probably need to create array of arrays:

<br />
ArrayList[] lists = new ArrayList[DEPTHS_COUNT];<br />

then go through all nodes using recursion:

<br />
void Traverse(TreeNode tn, ref ArrayList[] lists, int depth) {<br />
<br />
  lists[depth].Add(tn);<br />
<br />
  if (tn.Nodes.Count > 0)<br />
    foreach (TreeNode node in tn.Nodes)<br />
      Traverse(node, ref lists, depth + 1);<br />
}<br />

...and the last step is to split lists into one list:

<br />
ArrayList nodeList = new ArrayList();<br />
<br />
foreach (ArrayList list in lists)<br />
  foreach (TreeNode tn in list)<br />
    nodeList.Add(tn);<br />

Is that what you need?

Re: Algorithm for creating a list from a hierarchy?

Lars Niedziolka28-Jul-05 16:00

Lars Niedziolka

28-Jul-05 16:00

Hi Judah,

It's not difficult.

Use following call

ArrayList = ListOfTree(myTree);

and implement ListOfTree with this:

static ArrayList ListOfTree(TreeView tree)
{
  ArrayList list = new ArrayList();
  <small>// Add 1st level:</small>
  list.AddRange(tree.Nodes);

  <small>// Add 2nd, 3rd, 4th,... level</small>
  for (int idx = 0; idx < list.count; idx++)
  {
    list.AddRange(((TreeNode)list[idx]).Nodes);
  }

  <small>// return the result list</small>
  return list;
}

Example:
You have this tree:

Tree
|-A1
| |-B1
| | |-C1
| | +-C2
| +-B2
|   +-C3
+-A2
  +-B3

First you add the Nodes of the tree:

List := A1 A2  [from Tree]

Second you add each child of the already listed nodes: A1 A2

List := A1 A2 B1 B2 [from A1]
List := A1 A2 B1 B2 B3 [from A2]

And so on for each child of B1 .. B3

List := A1 A2 B1 B2 B3 C1 C2 [from B1]
List := A1 A2 B1 B2 B3 C1 C2 C3 [from B2]
List := A1 A2 B1 B2 B3 C1 C2 C3 [from B3]

And so on for each child of C1 .. C3

List := A1 A2 B1 B2 B3 C1 C2 C3 [from C1]
List := A1 A2 B1 B2 B3 C1 C2 C3 [from C2]
List := A1 A2 B1 B2 B3 C1 C2 C3 [from C3]

Have fun,
Niedzi

Re: Algorithm for creating a list from a hierarchy?

Judah Gabriel Himango28-Jul-05 17:04

Judah Gabriel Himango

28-Jul-05 17:04

Excellent, thanks.

Tech, life, family, faith: Give me a visit.
I'm currently blogging about: Homosexuality in Christianity
Judah Himango

Re: Algorithm for creating a list from a hierarchy?

leppie28-Jul-05 23:36

leppie

28-Jul-05 23:36

Judah Himango wrote:
efficient algorithm

Anyway u look at a tree traversal, it will almost allways be an O(n) operation.

^{xacc-ide 0.0.15 now with C#, MSIL, C, XML, ASP.NET, Nemerle, MyXaml and HLSL coloring - Screenshots}

How can I..

KORCARI28-Jul-05 11:50

KORCARI

28-Jul-05 11:50

How to show information about a picture in a picture box when put mouse over?

Re: How can I..

Judah Gabriel Himango28-Jul-05 12:04

Judah Gabriel Himango

28-Jul-05 12:04

Label myLabel = new Label();
myLabel.Text = "here is an interesting pic";

myPictureBox.Controls.Add(myLabel);

Tech, life, family, faith: Give me a visit.
I'm currently blogging about: Homosexuality in Christianity
Judah Himango

.Using C# dlls in MFC

benwalker28-Jul-05 11:25

benwalker

28-Jul-05 11:25

Hi
Okay, this is my first post so please bear with me..

Anyhow. I'm working on an oldish MFC application that uses dlls as 'plugins' - similar to Photoshop, Cubase etc. Now as part of my attempts to bring some of this kicking and screaming up to date, I'm trying to add another dll for use, written in C#.

I've done the 'use managed extensions' trick, and can instantiate the C# dll by adding it as a reference, and all seems to behave as expected - but I'm having some difficulty then handling the C# form's OK/Cancel. Ideally, I'd like any information or data contained within the C# form to be passed back to the MFC form - more as a verification that whatever the dll is supposed to do has been carried out successfully or not (plus as a demo of language interoperability it seems a good idea to persuade the nay-sayers).

I figure it's going to be done through interop - so pass a handle to the parent CWnd to the the C# dll, and then post a message to it once the dll 'ok' button is pressed - but where is my main starting point for going about this? Is this the best way to go about it, or is there something I've overlooked?

thanks,

benwalker

Re: .Using C# dlls in MFC

Judah Gabriel Himango28-Jul-05 12:24

Judah Gabriel Himango

28-Jul-05 12:24

Do you have control over when the C# form is launched? If so, can't you just go (in Managed C++):

DialogResult result = launchedForm->ShowDialog();
if(result == System.Windows.Forms.DialogResult::OK)
{
}

Maybe I'm not understanding your problem.

Tech, life, family, faith: Give me a visit.
I'm currently blogging about: Homosexuality in Christianity
Judah Himango

Re: .Using C# dlls in MFC

Anonymous29-Jul-05 7:14

Anonymous

29-Jul-05 7:14

hmm. now why didn't I think of that one - well, it saves going through interop or something else. I forget the fact that managed c++ has access to the same type of messages.. anyway - that seems to work:

thanks

benw

Autofill web form

tomc28-Jul-05 10:56

tomc

28-Jul-05 10:56

Hi,

My application needs to login to a web site automatically. Is it a way to programtically fill in the username and password web fields from a .NET windows form?

Thanks.

Image to WallPaper

sahoREGS28-Jul-05 10:44

sahoREGS

28-Jul-05 10:44

Is there a program where I allow the user to pick an Image from a Windows form and allow them to make that into a desktop WallPaper. Confused | :confused:

sahoREGS

Re: Image to WallPaper

Matt Gerrans28-Jul-05 12:46

Matt Gerrans

28-Jul-05 12:46

I'm not sure if there is something in the .NET library, but if all else fails you can use the API call SystemParametersInfo() to do it.

Matt Gerrans

Re: Image to WallPaper

[Marc]28-Jul-05 21:27

[Marc]

28-Jul-05 21:27

There's a registry key for something like that:
HKEY_CURRENT_USER\Control Panel\Desktop\
There you've got some values like ConvertedWallPaper, OriginalWallpaper, Wallpaper enz.
Hope this helps! Cool | :cool:

"..Commit yourself to quality from day one..it's better to do nothing at all than to do something badly.."
-- Mark McCormick

can we create a button array

iramg28-Jul-05 8:50

iramg

28-Jul-05 8:50

hi can anyone tell me that can we create a button array if we can then how we will display a button using that array on the form or write text on that button.
please tell me soon

Re: can we create a button array

Libor Tinka28-Jul-05 9:31

Libor Tinka

28-Jul-05 9:31

Why do you need to create button array? I don't know what are you working on, but array of buttons can be initialized as well as any other array:

Button[,] abtn;

of if you want jagged array, use:

Button[][] abtn;

Then traverse all buttons using for cycle and set their properties:

Button btn = Button[3, 2];

btn.Size = btnSize;
btn.Parent = this;

...

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