|
 Thanks. This clears my doubt regarding APPDOMAIN and multithreading.
|
|
|
|
|
Hi everybody,
I have a DataGrid in my form that bound to a DataSet, I use background thread to update the data in the dataset, bacause there are a few threads working behind, I don;t want the updated data to be displayed in the Grid until all the threads finish. I try to use SuspendBinding, but it doesn't work.
Does anybody have idea of how to solve it?
Thanks
Alan
Alan Shen
MCAD for .NET Version
^~^~^~^~^~^~^~^~^~^~^
Great idea is the beginging of success!
|
|
|
|
|
You could, of course, create two DataSets, and with a simple assignment when your worker thread completes its operation, have the data inserted into the second data set. Then call the Data Binding method, binding to the second data set, and Refresh.
I'll bet you already thought of that, though,...
|
|
|
|
|
Hi everybody,
I want to insert thousands of rows into an Access database, I use OleDbCommand to execute the insert sql, but it works pretty slow,
is there any good way to solve the problem?
Thanks for any help in advance!
Alan
Alan Shen
MCAD for .NET Version
^~^~^~^~^~^~^~^~^~^~^
Great idea is the beginging of success!
|
|
|
|
|
Actually, in my experience whery big ammount of inserts is allways not too fast, especially if you are executing it in some kind of for() or while() cycle.
Some time ago I created a 2D map in database where insert was wery simple like that: insert (x,y, <somemaptype>) values (1,2,34). In my case I used 2 for() cycles and OdbcConnection with OdbcCommand. insert statement was executed 1`000`000 times and it took 15-20 minutes because someMapType was Random generated number.
I suggest you have to check and try optimize your code, maybe even create transaction sql file and execute it in database side with you oledb. And there is one more thing - Access is the sickest database I ever seen. Maybe you should try some other database.
|
|
|
|
|
I used to use classwizard in VC++ 6.0, to add functionality of an event(eg: to override onLButtondown in view class).
I think, The classwizard is not available in VC++ 7.0(.Net version). So how to add this event.
Should I manually add the function signature in c++ and header file?
Thanks
Vinay
|
|
|
|
|
Go to the implementation file for the dialog, and then in your Properties window and there should be a toolbar button in it with a green block. Clicking it will list the available MFC overrides.
"Your coding practices might be buggy, but your code is always right."
Internet::WWW::CodeProject::bneacetp
N-Tech Productions
http://www.n-tp.com/
|
|
|
|
|
|
You're welcome. 
"Your coding practices might be buggy, but your code is always right."
Internet::WWW::CodeProject::bneacetp
N-Tech Productions
http://www.n-tp.com/
|
|
|
|
|
Hi,
I am experiencing some weird problems with an ASP.NET web application that is making use of System.Data.DataSet and System.Data.DataRow classes.
On a machine with single CPU, the application is running fine.
On a machine with Hyperthreading CPU, after a couple of seconds of running OK, the
application is crashing and the stack dump indicates that the error appears when trying to write in a System.Data.DataRow object.
If I am disabling the CPU Hyperthreading feature the application runs OK also on this machine.
Did anyone experienced also issues like this ?
Here it is the stack dump:
Source Error:
Line 1834: }
Line 1835: set {
Line 1836: this[this.tableSubscription.RequiredStatusColumn] = value;
Line 1837: }
Line 1838: }
Source File: c:\inetpub\wwwroot\CDS\DectDataSet.cs Line: 1836
(My note: this file is auto-generated from an XML schema file)
Stack Trace:
[NullReferenceException: Object reference not set to an instance of an object.]
System.Data.RecordManager.NewRecordBase() +49
System.Data.DataTable.NewRecord(Int32 sourceRecord) +20
System.Data.DataRow.BeginEdit() +42
System.Data.DataRow.set_Item(DataColumn column, Object value) +260
CDS.SubscriptionRow.set_RequiredStatus(Int32 value) in c:\inetpub\wwwroot\CDS\DectDataSet.cs:1836
CDS.Subscription.Remove(ResultDelegate resultDelegate) in c:\inetpub\wwwroot\cds\subscription.cs:752
CDS.SubscriptionManagement.Remove(String number) in c:\inetpub\wwwroot\CDS\SubscriptionManagement.cs:764
CDS.SubscriptionsForm.m_cmdRemove_Command(Object sender, CommandEventArgs e) in c:\inetpub\wwwroot\CDS\SubscriptionsForm.aspx.cs:736
System.Web.UI.WebControls.LinkButton.OnCommand(CommandEventArgs e) +110
System.Web.UI.WebControls.LinkButton.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +115
System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +18
System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +138
System.Web.UI.Page.ProcessRequestMain() +1277
Thanks is advance to anyone that can provide me some information in order to address this issue.
|
|
|
|
|
Sounds like a threading issue. A multithreaded app can perform fine on a single proc system, but if there is a threading problem it will not always make itself known. To truly test any application that uses several threads you should run it on a dual or more processor system.
|
|
|
|
|
Indeed, furhter investigations showed that is a threading issue. Although my application does not explicitely create any thread (this is what lead me into confusion), it also uses the delegation mechanism and I have understood that this mechanism creates background threads in order to implement the asynchronous notifications.
So I think the solution is to add some extra synchronizations on the DataSet/DataRow objects since these are the object that are shared between the various delegates.
|
|
|
|
|
Hi all
I have written a program which connects socket and send request to the server , gets the response. in this request i want to set the headers. then the response from the server must be .xml. i have done this by using httpwebrequest and httpwebresponse. now i am trying to do using sockets. if u have any idea on this please help me out.
Regards
Forum
|
|
|
|
|
|
Hi
Thanq for responding. but the thing is i am passing the all the information as a string. in this i concatenated my own headers. but it's not giving any values here. response is also like this
HTTP/1.1 200 OK\r\nServer: Microsoft-IIS/5.0\r\nDate: Mon, 07 Mar 2005 11:58:54 GMT\r\nX-Powered-By: ASP.NET\r\nConnection: close\r\nTransfer-Encoding: chunked\r\nCache-Control: private\r\nContent-Type: text/html; charset=utf-8\r\n\r\n43\r\nThe Action Engine Server is alive.3/7/2005 3:58:54 AM \r\n0\r\n\r\n
but i want xml file which comes from the server.
if u have an idea on this please do reply.
Thanks
Kavitha.
Forum
|
|
|
|
|
Being a newbee to the .NET stuff, I'm currently developing Web versions of my Company's apps and am having a very frustrating time with something that should be very easy.
I've created an app which uses OledbDataAdapters/DataSets which handle the data and display it in DataGrids.
When I originally created them, the data adapters were visible as Icons at the bottom of the Design View and all I had to do to modfy them was to right click and select properties, or whatever. However, now they are not visible any more and I need to modify them. How do I get the Icons back? Is it really obvious and I'm just being plain dumb? I don't ever remember deciding to hide them!
Thanks for your patience and any help that you can give.
code dope.
Life's like a sh*t sandwich - the more bread you got, the less sh*t you gotta eat!
|
|
|
|
|
The first thing that comes to mind is to ask if they still exist. Are you able to run the program in the debugger? or do the dataAdaptor and dataSet names in your code have squiggles under them? Either of those two things would show that they don't exist anymore and somehow were deleted.
If the program runs and/or the names don't have squiggles, then did the little window the icons appear in get shrunk? Look at the bottom of the design view window. Is there little shadded area with scroll arrows on the right right side? If so, place the cursor on the edge and drag it up till you see the icons.
|
|
|
|
|
Definatly worth checking out,
Cω @ Microsoft Research[^]
Its similar to C#, but does a great job of bridging the gap between relational and hierarchal data. With Cω, you can run an XPath query or SQL query on any .NET object
Hope this isnt a repost
|
|
|
|
|
Concepts from Comega are continually being added to the C# langauge. For instance, nullable types with the question mark syntax will be merged into C# 2.0 later this year. If you peruse through Channel9.msdn.com, you'll find that the C# language creator, Anders Heiljsberg, discusses that data-bound applications will be the primary focus of C# 3.0; they will most likely implement some of the query syntax from Comega.
One thing I really like about the language is its asynchronous execution syntax in the form of chords. I find dealing with threads and callbacks too low-level for some tasks, I hope to see a similar construct come to C# in the near future.
Tech, life, family, faith: Give me a visit.
I'm currently blogging about: Lies of Our Fathers: A Must-Know About Lent
Judah Himango
|
|
|
|
|
hi guys,I get some marvelous error from my c# program again & again, i guess it is a security exception error, so i disable security with caspol -s off, give it full trust, copy it to hard drive, copy it to cd drive, sign it with public/private key, in all these cases i got the same exception, i use framework 1.1.4322. and just want to read the file, not write to it, also i am admin of my computer! and it is in the same directory. why i got this error?
below you can see the exception text.
access to the path "g:\saving document6.cad" is denied
See the end of this message for details on invoking
just-in-time (JIT) debugging instead of this dialog box.
************** Exception Text **************
System.UnauthorizedAccessException: Access to the path "G:\saving document6.cad" is denied.
at System.IO.__Error.WinIOError(Int32 errorCode, String str)
at System.IO.FileStream..ctor(String path, FileMode mode, FileAccess access, FileShare share, Int32 bufferSize, Boolean useAsync, String msgPath, Boolean bFromProxy)
at System.IO.FileStream..ctor(String path, FileMode mode)
at wordtraining.main.lessonup()
at wordtraining.main.lbxLesson_DoubleClick(Object sender, EventArgs e)
at System.Windows.Forms.Control.OnDoubleClick(EventArgs e)
at System.Windows.Forms.ListBox.WndProc(Message& m)
at System.Windows.Forms.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
************** Loaded Assemblies **************
mscorlib
Assembly Version: 1.0.5000.0
Win32 Version: 1.1.4322.573
CodeBase: file:///c:/winnt/microsoft.net/framework/v1.1.4322/mscorlib.dll
----------------------------------------
wordtraining
Assembly Version: 1.0.1249.40111
Win32 Version: 1.0.1249.40111
CodeBase: file:///C:/Program%20Files/Rayan/wordtraining/wordtraining.exe
----------------------------------------
System.Windows.Forms
Assembly Version: 1.0.5000.0
Win32 Version: 1.1.4322.573
CodeBase: file:///c:/winnt/assembly/gac/system.windows.forms/1.0.5000.0__b77a5c561934e089/system.windows.forms.dll
----------------------------------------
System
Assembly Version: 1.0.5000.0
Win32 Version: 1.1.4322.573
CodeBase: file:///c:/winnt/assembly/gac/system/1.0.5000.0__b77a5c561934e089/system.dll
----------------------------------------
System.Management
Assembly Version: 1.0.5000.0
Win32 Version: 1.1.4322.573
CodeBase: file:///c:/winnt/assembly/gac/system.management/1.0.5000.0__b03f5f7f11d50a3a/system.management.dll
----------------------------------------
System.Drawing
Assembly Version: 1.0.5000.0
Win32 Version: 1.1.4322.573
CodeBase: file:///c:/winnt/assembly/gac/system.drawing/1.0.5000.0__b03f5f7f11d50a3a/system.drawing.dll
----------------------------------------
AxMP3PLib
Assembly Version: 1.0.0.0
Win32 Version: 1.0.0.0
CodeBase: file:///C:/Program%20Files/Rayan/wordtraining/AxMP3PLib.DLL
----------------------------------------
MP3PLib
Assembly Version: 1.0.0.0
Win32 Version: 1.0.0.0
CodeBase: file:///C:/Program%20Files/Rayan/wordtraining/MP3PLib.DLL
----------------------------------------
Accessibility
Assembly Version: 1.0.5000.0
Win32 Version: 1.1.4322.573
CodeBase: file:///c:/winnt/assembly/gac/accessibility/1.0.5000.0__b03f5f7f11d50a3a/accessibility.dll
----------------------------------------
************** JIT Debugging **************
To enable just in time (JIT) debugging, the config file for this
application or machine (machine.config) must have the
jitDebugging value set in the system.windows.forms section.
The application must also be compiled with debugging
enabled.
For example:
<configuration>
<system.windows.forms jitdebugging="true">
When JIT debugging is enabled, any unhandled exception
will be sent to the JIT debugger registered on the machine
rather than being handled by this dialog.
|
|
|
|
|
An UnauthorizedAccessException is thrown when an I/O routine gets an Access Denied error from the OS. You obviously don't have permission to perform this operation at that location.
In the FileStream constructor, ensure you're using FileMode.Open and FileAccess.Read. You may also get an access denied error if another process has the file open and has not allowed concurrent reading from the file (file share mode does not include 'Read').
Stability. What an interesting concept. -- Chris Maunder
|
|
|
|
|
hi, mike
I want to thank's for your repy, you are really a genius.
best regards.
|
|
|
|
|
Hi, everybody,
when I bound a DataSet to DataGrid, and turn on the sort function of DataGrid, I can change the listed order by click the Header of column in DataGrid.
I can get the current selected row of DataGrid by currentselectedrowindex, is there any way to get the datarow in the related dataset.
Thanks,
alan
Alan Shen
MCAD for .NET Version
^~^~^~^~^~^~^~^~^~^~^
Great idea is the beginging of success!
|
|
|
|
|
Try it with the BindingManager. See the following code:
BindingManager bm = baseDataGrid.BindingContext(baseDataGrid.DataSource,BaseDataGrid.DataMember];
if (bm.Count>0)
{
DataRow dr=((DataRowView)bm.Current).Row;
}
Regards
Uwe
|
|
|
|
|
Sorry! Here is the correct code:
BindingManagerBase bm = baseDataGrid.BindingContext(baseDataGrid.DataSource,BaseDataGrid.DataMember];
if (bm.Count>0)
{
DataRow dr=((DataRowView)bm.Current).Row;
}
Regards
Uwe
|
|
|
|
General 
News 
Suggestion 
Question 
Bug 
Answer 
Joke 
Praise 
Rant 
Admin 
Submit an article or tip
