|
In a DataGrid with a data source of DataTable,
What's the difference between a column_changed event and a column_changing?
When editing the data table during runtime, it first enters the column_changing method, then the column_changed one.
I want to invalidate the user's editing in a column according to a certain criterion.
Thanks!~
Here is Rebecca.
|
|
|
|
|
Rebecca Gao wrote:
What's the difference between a column_changed event and a column_changing?
changed is in the past tense
changing is in the present continuous tense
Therefore:
* The ..._changing event fires as the change is taking place, giving you a chance to cancel the change or other action you need to complete before the change is completed.
* The ..._changed event fires after the chance has been made, giving you a chance to perform actions that rely on the change having successfully completed.
Do you want to know more?
|
|
|
|
|
Hi,
Do any one know how to call a windows service in the web service. A line of code will be great.
Thanks in advance,
Sreepathi.
|
|
|
|
|
I am looking for a combined tree and grid control.
It should display nodes in a hierarchy (showPlusMinus and showRootLines) like a tree view. Mostly, it should look like a treeview.
It should also display columns with column headers, though, like a grid. The master/child datagrid doesn't really do a good job for this.
I've tried starting with grid, and adding my own PlusMinux boxes and RootLines, and I've tried starting with a treeview, and breaking up each line into columns with column headers. Either way, it's going to be a ton of work so that the custom control has good support for both grid stuff and tree stuff.
I realize that I can purchase for $$$ money several different grids that do trees very well, but I'm cheap. I'm surprised that no-one has published source code to a free version that I can use.
Does anyone have something like this they'd like to share?
Thanks,
Norman R.
|
|
|
|
|
|
Hi,
I've been working on an async download class. It's basiclly complete but I need to raise some events from a thread started with BeginInvoke. When I raise the event it works fine but if I want to modify the user interface I understand that it needs to be running on the UI thread (I checked the InvokeRequired property and it is true). What I'm trying to work out is how I can automatically run the events on the thread the class was created in. Any help would be appreciated!
On a side-note I looked at the .net 2.0 implementation of an async download (in the WebClient class) but it uses alot of new classes (like AsyncOperation) which I cant use in 1.1.
Dan
EDIT: Oh and heres the class incase anyone wants to take a look at it. 
http://homepages.paradise.net.nz/dannyres/FileDownload.cs[^]
|
|
|
|
|
You need to Invoke again on the thread the gui runs from.
when the event fires and you receive it on your form instead of updating your control directly you would need to do it through another delegate.
public delegate void UpdateControlHandler(string text);
private void UpdateControl(string text)
{
this.mycontrol.Text = text;
}
private void GotMyEvent(object sender,MyEventArgs e)
{
if(this.InvokeRequired)
{
object [] args = new object[1];
args[0] = e.text;
this.Invoke(new UpdateControlHandler(this.UpdateControl),args);
}
else
{
this.UpdateControl(e.text);
}
}
hope this helps
it works for me
|
|
|
|
|
Although this does work its not really what I would like.. I'm wondering if theres a way todo this so its automatically on the UI thread and whoever is using the class doesnt have to use Invoke..? Is this even possible? :P
Dan
|
|
|
|
|
Hi
can any one tell me
1) how can i reach to Yahoo messenger from my vb.net
program and identify add and remove ID and ... and how can i send & recieve
message from my program to/from other yahoo messenger id?
(Port number that yahoo used and ...)
2) how can i make my id that used in my program always on?
i hope you understand what i mean !!!! 
Best Regards
M.Khayatan
MkhProgrammer
|
|
|
|
|
I have a nested loop in which I am looking at username and password if they click more than 3x's I lock them out... However, my loop won't work... Here is the code
While DR.Read()
'If i <= 3 0 Then
If User = DR("DTLoginID").ToString() And Pwd = DR("DTPassword").ToString() Then
Response.Redirect("Broadcast.aspx")
ElseIf User = DR("DTLoginID").ToString() And Pwd <> DR("DTPassword").ToString() Then
MsgBox.alert("The Username and/or Password does not exist; Please Try Again")
Me.txtUser.Enabled = True
' i = i + 1
ElseIf User <> DR("DTLoginID").ToString() And Pwd <> DR("DTPassword").ToString() Then
MsgBox.alert("The Username and/or Password does not exist; Please Try Again")
Me.txtUser.Enabled = True
' i = i + 1
End If
'ElseIf i > 3 Then
'MsgBox.alert("No User Exist")
'Response.Redirect("Broadcast.aspx")
' End If
End While
It will go straight to the (marked out items) elseif i > 3 and do the redirect.... any suggestions..
|
|
|
|
|
You might want to try an Exit Sub after each of the if traps. You might be getting stuck in your while loop after one of your conditions has been met.
While DR.Read()
'If i <= 3 0 Then
If User = DR("DTLoginID").ToString() And Pwd = DR("DTPassword").ToString() Then
Response.Redirect("Broadcast.aspx")
Exit Sub ''''<addded code="">>>>
ElseIf User = DR("DTLoginID").ToString() And Pwd <> DR("DTPassword").ToString() Then
MsgBox.alert("The Username and/or Password does not exist; Please Try Again")
Me.txtUser.Enabled = True
' i = i + 1
Exit Sub ''''<addded code="">>>>
ElseIf User <> DR("DTLoginID").ToString() And Pwd <> DR("DTPassword").ToString() Then
MsgBox.alert("The Username and/or Password does not exist; Please Try Again")
Me.txtUser.Enabled = True
' i = i + 1
Exit Sub ''''<addded code="">>>>
End If
'ElseIf i > 3 Then
'MsgBox.alert("No User Exist")
'Response.Redirect("Broadcast.aspx")
Exit Sub ''''<addded code="">>>>
' End If
End While
Best of luck
Forever Developing
|
|
|
|
|
While DR.Read()
If i <= 3Then
If User = DR("DTLoginID").ToString() And Pwd = DR("DTPassword").ToString() Then
Response.Redirect("Broadcast.aspx")
ElseIf User = DR("DTLoginID").ToString() And Pwd <> DR("DTPassword").ToString() Then
MsgBox.alert("The Username and/or Password does not exist; Please Try Again")
Me.txtUser.Enabled = True
' i = i + 1
ElseIf User <> DR("DTLoginID").ToString() Then
MsgBox.alert("The Username and/or Password does not exist; Please Try Again")
Me.txtUser.Enabled = True
' i = i + 1
End If
'ElseIf i > 3 Then
'MsgBox.alert("No User Exist")
'Get to the screen where you want user to know that user is been locked
exit while
' End If
End While
|
|
|
|
|
I am interested in dividing my components into run-time and design-time components. I want to do this so that code I only need for design time is not included in the run-time component, which is shipped to an end-user. The design time component would only be needed by the programmer when making use of the design-time capabilities of my component, such as using it in the Windows form designer.
It does not appear this is possible in .NET. I can still certainly divide my component into two different assemblies, one for run-time code and one for design-time code. But it seems there are two reasons that I can not make the sort of clean division in which both assemblies need to be available at design time while the run-time assembly only needs to be available at run-time.
The first reason is that the classes I use for my design time code, derived from System.ComponentModel, do not necessarily only pertain to design time functionality. According to the documentation on type converters, as an example, they might apply both to design time and run-time. There seems no way to specify that a type converter, which I would put in my design-time assembly should only pertain to design-time code.
Secondly to use the classes in my design time assembly at design time, I must provide attributes for the types and properties to which the design-time classes pertain in my run-time assembly and, since the attributes refer to classes in another assembly, the run-time assembly must reference that other design-time assembly. This effectively ties my run-time assembly to these classes which I only want to use at design time.
Has this issue been addressed or discussed anywhere ? It does seem to me wasteful that .NET classes which I create only for design-time functionality needs to be distributed to the end-user by a programmer who uses my component, even though the end-user will never need the functionality. Furthermore I see no way to tell .NET that the casses which I create for design-time functionality should only be used at design time and not run-time.
Because of these issues, I have a feeling that there must be a way to create a design time assembly for my component which does not have to be unnecessarily shipped to end-users as part of run-time execution. Does anybody know how to do this ?
Edward Diener
|
|
|
|
|
Hi,
Is there a way to increase the height of a list view item?
Also, if the font is increased to, say, 10 from 8.25 (default), the text gets truncated in display and the full letter(s) is/are not visible in the available item height.
anyone knows a way out?
any help/suggestion appreciated.
Thanks.
|
|
|
|
|
Thank you Valadatanciu
I do use Abort() function for the thread before exit the program. It has not being helping.
Simply by calling Application::Exit() will still keep the instance of the process. I tried it before and I tried today after seeing your post. The results were same.
I do not have same problem in C#. Calling Application.Exit() will clear the process in C#. I wonder C++ side did not do good job on garbge collection work as MS declared.
|
|
|
|
|
Application::Run(new FormFoo()); starts a new application based on FormFoo, what means that starts the wndProc based on that window. so basicly if you close the window with this->Close(); the FormFoo wndProc will not process anymore windows messages and your code will continue runing from winmain and stop the thread exectution with return 0;
how do you exit your program? with Application::Exit(); or with this->Close(); (i recomand the first option)?
by the way my name is Vlad Stanciu not valalalal 
I hope you understand...
By the way... visit http://nehe.gamedev.net[^]
|
|
|
|
|
Thank you very much for trying to help again, Vlad.
Sorry I just copied your ID Valadatanciu yesterday in my reply since I did not know your name.
I always use Application::Exit() to terminate my programs in .net. Yesterday, I found that the reason not working this time, was I used a thread and suspend it during the middle of execution, then computer did not like it so even when I called Application::Exit(), the process was still alive. After I took the suspend() function out, it closed properly. What a mess!
Thank you again.
|
|
|
|
|
Hi ,
As anyone encountered an error message stating that the form that was specified as the MDI Parent is not an MDIContainer. I can understand that this would arise when the form has not had the IsMDiContainer property to true however i have set this property and the application was running fine until yesterday evening any ideas. i am about to unistall framework and VS2003 and reload.
Can anyone help?
Cheers
dazzler
|
|
|
|
|
I use managed C++ and use Application::Exit() to terminate my program. The GUI was gone after call the function. However, the process is still in my Windows Task Manager. How can I kill the process when I exit the program?
My code starts at:
int APIENTRY _tWinMain(HINSTANCE hInstance,
HINSTANCE hPrevInstance,
LPTSTR lpCmdLine,
int nCmdShow)
{
System::Threading::Thread::CurrentThread->ApartmentState = System::Threading::ApartmentState::STA;
Application::Run(new MainForm());
return 0;
}
and end with:
MainForm::Close();
Application::ExitThread();
Application::Exit();
Anything missing here? Your help will be greatly appreciated.
|
|
|
|
|
your thread is still runnig probabliy because you didn't do a good cleaning (you leted some objects that couldn't be closed opened)
I sugest you close the program by simply by calling Application::Exit(); this closes the window opened for message loop end exits the application.
if you are not satisfied by this mthod you colud always abort a thread (cause an imediatly close and resource freeing process) like this (for the curent thread) System::Threading::Thread::CurrentThread->Abort();
I hope you understand...
By the way... visit http://nehe.gamedev.net[^]
|
|
|
|
|
Good day all…
I am interested in adding the fading color (similar to the Windows Media Player version 10) scheme to my Main Menu. Does anyone have an object type or maybe guide to a location where I can complete this solution?
Thanks in advance for your assistance.
Have a great coding day.
Regards,
Tony D. Abel
|
|
|
|
|
I have the following code, but I cannot seem to get the changes in the dataset to be commited to the database. All I get is a 0 rowcount:
Private editQry As String = "select idc,nomiko,Eponymo,Onoma,Tel from Persons where idc=1"
Private adoCEDataAdapter As SqlCeDataAdapter
Private CustEditDataSet As DataSet
Private cb As SqlCeCommandBuilder
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
Me.Close()
End Sub
Private Sub frmCustEdit_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
adoCEDataAdapter = New SqlCeDataAdapter(editQry, frmConnect.adocon)
cb = New SqlCeCommandBuilder(adoCEDataAdapter)
CustEditDataSet = New DataSet
adoCEDataAdapter.Fill(CustEditDataSet)
txtSurname.DataBindings.Add(New Binding("Text", CustEditDataSet.Tables(0), "Eponymo"))
txtName.DataBindings.Add(New Binding("Text", CustEditDataSet.Tables(0), "Onoma"))
txtTel.DataBindings.Add(New Binding("Text", CustEditDataSet.Tables(0), "Tel"))
cbLegal.DataBindings.Add(New Binding("SelectedIndex", CustEditDataSet.Tables(0), "nomiko"))
End Sub
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
MsgBox(adoCEDataAdapter.Update(CustEditDataSet).ToString())
Me.Close()
End Sub
I have tried to create the Update query with:
adoCEDataAdapter.UpdateCommand=cb.GetUpdateCommand
and it returns a query, but again nothing happens on the adoCEDataAdapter.Update(CustEditDataSet)
Help....
|
|
|
|
|
Hi all,
I've created a new windows form application (C++) project,
and I can't see the form's events - not under the Properties window and not in the bar that is above my code editor. Do I have to add anything to support this?
thanks.
/=/=/=/= Sagmam =\=\=\=\
|
|
|
|
|
This is my first time delploying a windows application. I was able to deploy it to a computer that has .net installed but how do I deploy to a computer without .net installed. I think I need to add dotnetfx.exe to my installer but don't know how. Are their any walkthroughs out their that are simple to follow for a first timer? Please help.
Thanks in advance,
Beginner in VB.Net
|
|
|
|
|
You can do many things to get .NET installed on the target machine. InstallShield has .NET built in and will create an installer or if you have Visual Shtudio 2003 then you can use the PluginInstaller[^] from Microsoft and then just create a setup project and .NET will be included for you.
Steve Maier, MCSD MCAD
|
|
|
|
General 
News 
Suggestion 
Question 
Bug 
Answer 
Joke 
Praise 
Rant 
Admin 
Submit an article or tip
