I rarely say this - C# Discussion Boards

Event and EventHandler for communication required

27-Mar-07 4:19

Hello,

The System.IO.FileInfo class has the "MoveTo" method for this casses.

System.IO.FileInfo fi = new System.IO.FileInfo("oldName");
fi.MoveTo("newName");

All the best,

Martin

Starzfighter27-Mar-07 3:56

Starzfighter

27-Mar-07 3:56

Short explanation of the situation:
In my Form (main) i have embbeded a datagrid and a usercontrol with a panel inside on which i paint the names (nodes) of the datagrid.
for example in a treeview it would look like this:
food
+-meat
+-bread
###+-corn
###+-wheat
food can be bread or meat. On the panel of the usercontrol i draw then the food, the meat and the bread. Then i draw two lines to connect the food with the meat and the bread. Now i want to click on the bread and a contextMenu shouldappear with Next. When i click next it should repaint the panel with
bread
+-corn
+-wheat
To do so i need to go back to the datagrid and select the bread there. I have allready a method which selects me the right cell when i give it the text which item should be selected (here the string: bread). But here is my problem.
How do i send a message form the usercontrol to the form.
I was thinking it should work somehow with an event.
But i don't know exactly how to do it or where to start.
(Something like observer pattern)

I make an event in the usercontrol.
And the Form should notice it when the event is executed.
i thought on something like this:
in usercontrol:
public event EventHandler next = null;

and in the form:
usercontrol.next +=new EventHandler(usercontrol_back)

and then the handler for it.

private void usercontrol_next(object sender, EventArgs e)
{
//the method i need to call
}

but how do I say in my usercontrol that the event should be fired or started?
How does my form notice that the event is fired in my usercontrol?
And how do i get the string from the usercontrol to my datagrid (in the form)?

Re: Event and EventHandler for communication required

Not Active27-Mar-07 5:21

Not Active

27-Mar-07 5:21

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpguide/html/cpconeventsdelegates.asp[^]

only two letters away from being an asset

Passing Recordset from C# COM to VBScript

rahvyn627-Mar-07 3:49

rahvyn6

27-Mar-07 3:49

I am working on a COM dll in C# that needs to pass an ADODB recordset back to
the calling VBScript. I believe I have everthing setup correctly, as the
calls work, and it looks like a recordset is returned, however, the recordset
is null or closed. What is the trick to passing a recordset back from C#?

The Call:
Set rs = CreateObject("Interface")
rs.Init "System", "ODBC", "user", "pass", "database", "server"
retVal = rs.DataImport("value")

C#:
using ADODB;

[Guid("C3C26A94-9639-43c4-B59C-E245C8A68D44")]
[InterfaceType(ComInterfaceType.InterfaceIsIDispatch)]
public interface iInterface
{
[DispId(1)] bool DataExport(string OrderNumber, string
TrackingNumber, decimal Freight, decimal Weight, string ShipDate, string
ShipVia, string MiscNum);
[DispId(2)] bool DataVoid(string OrderNumber, string TrackingNumber,
decimal Freight, decimal Weight, string MiscNum);
[DispId(3)] Recordset DataImport(string OrderNumber);
[DispId(4)] void Init(string nameVal, string odbcVal, string
userVal, string passVal, string dbVal, string srvVal);
}

[Guid("EF8369F0-CF42-40b1-B3F3-0EC54CE73FF4")]
[ClassInterface(ClassInterfaceType.None)]
[ProgId("Interface")]
public class PSIHeader:iInterface
{

public Recordset DataImport(string OrderNumber)
{
//misc stuff - create connection, query etc...
//Recordset creation and return
rs.CursorLocation = CursorLocationEnum.adUseClient;
rs.Open(query.ToString(), cn, ADODB.CursorTypeEnum.adOpenForwardOnly, ADODB.LockTypeEnum.adLockOptimistic, -1);

return rs;
}
}

I have been using regasm to register the type library.

Thanks

end (break)

SVb.net27-Mar-07 3:46

SVb.net

27-Mar-07 3:46

hi, i need to know how i can exit from sub(method) in c#, i mean keywork like exit sub in vb.net

123

Re: end (break)

Christian Graus27-Mar-07 3:48

How could i dispose a windows form.

27-Mar-07 3:48

return;

But, it is better to have only one return statement and use conditionals to control what code is executed. Refactoring often helps.

Christian Graus - Microsoft MVP - C++
Metal Musings - Rex and my new metal blog
"I am working on a project that will convert a FORTRAN code to corresponding C++ code.I am not aware of FORTRAN syntax" ( spotted in the C++/CLI forum )

I rarely say this

Ennis Ray Lynch, Jr.27-Mar-07 5:13

Ennis Ray Lynch, Jr.

27-Mar-07 5:13

But I am so glad at least one other person in the world shares my philosophy about return statements.

File Not Found

Re: end (break)

SVb.net28-Mar-07 6:38

SVb.net

28-Mar-07 6:38

i know this keyword(return) but this keyword use in function,i need like this keyword in method
example
public void f()
{
1: command (Execute
2: Command (Execute
exit sub (in vb.net) (what i can write here like this code in c#)
3: Command (not Execute
4: Command (Not Execute
}

123

Test27030727-Mar-07 3:40

Test270307

27-Mar-07 3:40

Suppose we have two form. FormA and FormB. FormA has a button. i want when i click the button then Form2 would be open and at that time FormA should be Dispose. but how i dispose FormA?

button click event:

Form2 oForm2=new Form2();
oForm2.ShowDialog();
this.Dispose();

but this code could not dispose the FormA.

Pls help me on this.

Martin#27-Mar-07 3:44

27-Mar-07 3:44

Hello,

You have to use the Show Method instead of ShowDialog.
and then Close (will call the Dispose method also) the FormA.

Form2 oForm2=new Form2();
oForm2.Show();
this.Close();

Does not work if FormA is your main form. Because then your program will end and all forms will be closed.

All the best,

Martin

Test27030727-Mar-07 3:53

Test270307

27-Mar-07 3:53

thanx martin.

Christian Graus27-Mar-07 3:48

27-Mar-07 3:48

Instead, you should create both forms as control, and put them both on the one form, showing one at a time.

Test27030727-Mar-07 4:06

Test270307

27-Mar-07 4:06

sorry, i can't get your point.

Christian Graus27-Mar-07 4:23

27-Mar-07 4:23

Create two user controls. Design each to look like one of the forms you need. Put both on a form. Alternate which one is Visible to decide which 'form' is showing.

Sending UDP packets

V.27-Mar-07 3:40

27-Mar-07 3:40

Guys,

consider following code:

byte [] bytes = new byte[160];
FillBytes(ref bytes);
System.Net.IPAddress ipaddress = new System.Net.IPAddress(1684300900);  //=100.100.100.100
System.Net.IPEndPoint ipendpoint = new System.Net.IPEndPoint(ipaddress, 7000);
//System.Net.IPEndPoint remoteendpoint = new System.Net.IPEndPoint(ipaddress, 7001);
udpclient = new UdpClient();
try{
    int sent  = 0;
    //udpclient.Connect(ipendpoint);
    //udpclient.EnableBroadcast = true;
        //udpclient.Client.Connect(ipendpoint);
    //udpclient.Connect(ipendpoint);
    //sent = udpclient.Send(bytes, bytes.Length);
    sent = udpclient.Send(bytes, bytes.Length, SystemInformation.ComputerName, 7000);
    MessageBox.Show(Encoding.ASCII.GetString(bytes));
    //sent = udpclient.Send(bytes, bytes.Length, ipendpoint);
    lbl_bytessent.Text = "Sent: " + sent;
    //udpclient.Client.Close();
}
catch(Exception ex){
    MessageBox.Show("send result: error: " + ex.Message);
}

PS: I left the comments to show what I've already tried Smile | :)

I need to send some bytes to a receiving application. I have a small example in VB6 where it seems to work, so I tried in C# to do the same. The bytes that are sent (is set in integer sent) is always correct, the function doesn't come in the catch. However, the receiving application does not seem to react, but it does so with the VB6 application. I'm guessing I need to set some relation between sender and receiver, but I can't figure out how.

Any help on this? According to the examples on MSDN, I'm quite correct?

Thanks !

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

Windows Forms

7127-Mar-07 3:22

27-Mar-07 3:22

hi,

i am having Form1,Form2,and Form3

In Form2 i am having some values like selecting a radioButton,check box,or entering some text in the textboxes.

then i will be moving to Form3..

Now how can i Save the content of Form2..

if i come back from Form3 to Form2 i should load my values..

Help me pls

With Regards
prasad Smile | :)

Re: Windows Forms

Christian Graus27-Mar-07 3:35

27-Mar-07 3:35

First, please tell me they are not called that...

The easiest way to do this is to make your forms controls within the one form, and change which one is visible. If Form2 disappears when Form3 shows, that's the best way to approach that, in general. The other way to do it, is to just hide Form2, instead of destroying it.

The controls approach is nicer.

Re: Windows Forms

Martin#27-Mar-07 3:40

27-Mar-07 3:40

Christian Graus wrote:
ForumC#
Subject:Re: Windows Forms
Sender:Christian Graus
Date:9:35 27 Mar '07

First, please tell me they are not called that...

Re: Windows Forms

Martin#27-Mar-07 3:36

27-Mar-07 3:36

Hello,

You could hold the Form2 instance in memory (Hide), instaed of disposing (Close) every time you change to ann other form.

All the best,

Martin

Large TXT files

Sabry190527-Mar-07 3:04

Sabry1905

27-Mar-07 3:04

Hello All
i am trying to read a large txt files -may 1 GB-, which coze my program to hang, and i need to know if there are techniques that make this without hang and do it faster
if you know something can help. please tell me.

Christian Graus27-Mar-07 3:13

27-Mar-07 3:13

The best thing is to avoid such files. You *can* read a file a line at a time, but I'm not sure if it loads in to memory anyhow when you do that. I'd hope not. What code are you using right now ? What is in the files ?

hakonvik27-Mar-07 3:22

hakonvik

27-Mar-07 3:22

Hi
You could consider using a backgroundworker to read the file, while showing a "loading" sign or something..
Big Grin | :-D

basically something like:

private void getTextFileWorker_DoWork(object sender, DoWorkEventArgs e)
{
//start to read the file, show loading sign...

while(morelinesinfile)
{
this.Invoke(new AddValueDelegate(AddValue), new object[] { valueFromFile });
}
}

private void AddValue(string valueFromFile)
{
//do something with the value, add it to a list...
}

private void getTextFileWorker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
//finish up etc..hide sign..
}

best regards
HV

Christian Graus27-Mar-07 3:36

27-Mar-07 3:36

I suspect the real issue is that 1 GB of text will, on most computers, mean your RAM is full and you're using virtual memory.