|
I am developing an application with Winforms (w/ C#).This application will work with MS SQL Server.The thing which made me confused is, my application should be noticed, whenever a update / insert generated in that dataSource.
My friend told me that I could handle this situation , using Sql TimeStamp Column..
I found an article ( http://www.codeproject.com/cs/database/Multi-Tier.asp[^]) which talks about the DBConcurrency
Do you have any other ideas rather than using TimeStamp , or should I solve my problem with these technique ?
If there is anything that you dont understand , please let me know ..
|
|
|
|
|
|
|
Hi,
I have to get the area value of a given building plan image. This is a floor plan image where I need to calculate area of a room in the floor plan or the whole area of the floor plan in square meters. I tried to get the pixel value but didn?t work. I can input a scale which the plan has been drawn but find it difficult to obtain the area.
Is there anyway to do that?
|
|
|
|
|
If anyone can answer either of these questions I would appreciate it greatly! Thanks!
1)I'm using the Microsoft Automation object for PowerPoint, but I'm running into a kind of problem. When I start hammering PowerPoint with requests it crashes (as one would expect). However, when this happens, I would like to be able to catch these exceptions without the user ever knowing.
2) All this time I've thought that I can simply load my automation object like this:
//Create an instance of PowerPoint.
oPPT = new PowerPoint.ApplicationClass();
// Show PowerPoint to the user.
oPPT.Visible = Microsoft.Office.Core.MsoTriState.msoFalse;
As opposed to what I havwe currently:
//Create an instance of PowerPoint.
oPPT = new PowerPoint.ApplicationClass();
// Show PowerPoint to the user.
oPPT.Visible = Microsoft.Office.Core.MsoTriState.msoTrue;
But to my dismay the first time that I tried putting in msoFalse I am suddenly confronted with the following error:
A first chance exception of type 'System.Runtime.InteropServices.COMException' occurred in PowerPointService.exe
Additional information: Application (unknown member) : Invalid request. Hiding the application window is not allowed.
I don't quite know how to get round that one!
Thanks SO much!
Jim
|
|
|
|
|
Esmo2000 wrote:
// Show PowerPoint to the user.
oPPT.Visible = Microsoft.Office.Core.MsoTriState.msoFalse;
What are you trying to do? If you want to show the application window of course Visible has to be set to msoTrue.
This posting is provided "AS IS" with no warranties, and confers no rights.
Software Design Engineer
Developer Division Sustained Engineering
Microsoft
[My Articles] [My Blog]
|
|
|
|
|
I am trying to make it so it is NOT visible. I don't know how to do that.
|
|
|
|
|
It's not visible unless you make it visible, so just don't set the Visible property.
This posting is provided "AS IS" with no warranties, and confers no rights.
Software Design Engineer
Developer Division Sustained Engineering
Microsoft
[My Articles] [My Blog]
|
|
|
|
|
When I try to not set the visible property it will continue to load okay, but then if I try to use any of the functionality of the program it won't work. For example, if i try to open a file it fails saying there is no active window.
Is there anyway that i can do my processing silently?
Sincere regards,
Jim
|
|
|
|
|
If PowerPoint requires an active window it requires an active window. Most likely this is due to how the animations work, but I don't know. What is obvious is that PowerPoint requires an active window.
This posting is provided "AS IS" with no warranties, and confers no rights.
Software Design Engineer
Developer Division Sustained Engineering
Microsoft
[My Articles] [My Blog]
|
|
|
|
|
Hi!
I am trying to serialize a class that contains a list of objects. Here's the situation:
<br />
[Serializable()]<br />
class A: ISerializable{<br />
ArrayList m_aList;
<br />
public A(){}<br />
<br />
public A(SerializationInfo info, StreamingContext ctxt)<br />
{<br />
}<br />
public void GetObjectData(SerializationInfo info, <br />
StreamingContext ctxt) <br />
{<br />
}<br />
}<br />
<br />
class B{<br />
string m_sName;<br />
public string Name{ <br />
get{return m_sName;} <br />
set{m_sName = value;}<br />
}<br />
public B(){}<br />
}<br />
So I need a way to serialize and unserialize the list of objects B contained in A. Normally, B would be a more complicated class with the serialization capabilities too.
Thanks!
Huck
|
|
|
|
|
First of all, your comments - and perhaps your thinking - are wrong in the sense that the serialization constructor is to deserialize data, while ISerializable.GetObjectData is to serialize data. You should read Serializing Objects[^] in the .NET Framework SDK for an overview and examples of serialization.
The easiest way to achieve what you want: don't implement ISerializable. Just attribute your class with the SerializableAttribute as you're currently doing. By default, any private or public members of a class are serialized for types that are serializable. If you implement ISerializable just pass the array to the SerializationInfo.AddValue method:
[Serializable]
public class MyClass : ISerializable
{
MyStruct[] structs;
protected MyClass(SerializationInfo info, StreamingContext context)
{
structs = (MyStruct[])info.GetValue("structs", typeof(MyStruct[]));
}
void ISerializable.GetObjectData(SerializationInfo info, StreamingContext context)
{
info.AddValue("structs", structs, typeof(MyStruct[]));
}
}
[Serializable]
public struct MyStruct
{
public string Field1;
public int Field2;
[NonSerialized] public string Field3
{
get { return Field1 + Field2.ToString(); }
}
}
This posting is provided "AS IS" with no warranties, and confers no rights.
Software Design Engineer
Developer Division Sustained Engineering
Microsoft
[My Articles] [My Blog]
|
|
|
|
|
Hi I am using asp.net and c# to create a web application and I am having trouble deleting records from my sql server database table if anyone has any ideas please help thanks in advance
Tadhg88
[code]DataTable concerts = concertDataSet1.Tables["Concert"];
foreach(DataRow myRow in concerts.Rows)
{
if(ConcertsListBox.SelectedItem.ToString() == myRow[0].ToString())
{
//*** put the new DataRow in the DataTable
concerts.Rows.Remove(myRow);
//*** update the database table using the dataset
sqlDataAdapter1.Update(concertDataSet1);
ConcertsListBox.DataBind();
return;
}
}[/code]
|
|
|
|
|
I think you've removed from concerts DatTable, not table in your DataSet. Use Remove method for concertDataSet1.Tables["Concert"].Rows.
Mazy
"One who dives deep gets the pearls,the burning desire for realization brings the goal nearer." - Babuji
|
|
|
|
|
See DateTimePicker.CustomFormat Property .
Mazy
"One who dives deep gets the pearls,the burning desire for realization brings the goal nearer." - Babuji
|
|
|
|
|
thnx
i have done it myself
i haveplaced 00:00:00 in the customformat instead of HH:mm:ss so i rote it here as a query
sukanya
|
|
|
|
|
HI
I have a datetimepicker contorl on a windows form which i have sent it to the time in the format property. it is in 12 hrs format i want to appear in 24 hrs format
Is there any way to do that?
Sukanya
|
|
|
|
|
EDIT: This problem is solved!
I'm building an application partly in C# (which I am learning currently) and the other part in C++.
What I want to do is pass a string or array of char's form my C++ dll to my C# exe. I seem to be able to pass basic data types, but when it comes to pointers or Strings or anything else, it either doest work, or my heap gets messed up or overwritten.
here is what I have in my C++ project
EXPORT void TestFunc(char* str)
{
str = ptr;
}
here is the C# stuff
[DllImport("My_C_PlusPlus.dll")]
public static extern void TestFunc( [MarshalA(UnmanagedType.LPTStr)] StringBuilder str);
StringBuilder temp = new StringBuilder(128);
TestFunc(temp);
and temp ends up NOT being correct;
But I tried this too
C++..
EXPORT char* TestFunc()
{
return ptr
}
C#...
String temp = TestFunc();
temp ends up being correct weather it’s a String or StringBuiler, but then my heap for my c++ dll gets jacked. I get an int 3 (user defined break) right away upon returning that function;
I also tried just using a char* in my C# project and assigning upon return from the dll function call but that didn’t work at all, the value ended up being all message. The problem is, one project thinks is some datatype and the other thinks its something else, so it never works. Is there some sort of unified data type for strings or pointers to strings that I can use here?
|
|
|
|
|
I tried it with LPTSTR in my dll with no luck either.
|
|
|
|
|
WHOA! figured it out
enough guessing and checking seemed to work, lol
inside the DLL: (C++)
EXPORT void MyFunc(LPTSTR pString)
{
strcpy(pString,"text");
}
inside the exe: (C#)
[DllImport("mydll.dll")]
public static extern void MyFunc( [MarshalAs(UnmanagedType.LPStr)] StringBuilder str);
StringBuilder temp = new StringBuilder(128);
What my problem was was, i was trying to use the string inside the c# project as a pointer to point to the stuff in the dll, but what i needed to do was pass a pointer to memory inside the exe to the dll and have it assign stuff there. No pointers in C# is kinda awkward for me as a (7+ years C++ coder)
anyway, im talking to myself, good night 
|
|
|
|
|
Hey guys,
I'm so sorry because this is probably one of the most stupid questions I ever asked, but hey, I once was a VB programmer and now started C#, you should be happy hearing that 
Now what's happening, I'm creating a databound control in C# which uses an Sql connection in order to fetch it's data. To establish the connection we need a connection string, and so I check for the existance of if. When the connectionstring property was not set, I want to throw an exception telling the user that the connectionstring was not set.
throw new SqlException("Connectionstring not set");
Now when compiling I get the warning
No overload for method 'SqlException' takes '1' arguments
I cannot find what's really meant here, and how to solve it... Any ideas?
I love it when a plan comes together
|
|
|
|
|
It means that the SqlException class provides no constructor that takes 1 argument, in your case the error message.
Taking a quick look at MSDN shows that the SqlException class provides no constructor at all, so you'll have to throw some other exception. Unless, someone knows a workaround.
www.troschuetz.de
|
|
|
|
|
Stefan Troschütz wrote:
Unless, someone knows a workaround
A workaround to a no-public-constructor object?!?!?
I guess you could instantiate through reflection if you were THAT desperate to have a SqlException.
|
|
|
|
|
Yup, I guess that should be it... Throwing an ArgumentException in case of an SqlException solves the problem.
I love it when a plan comes together
|
|
|
|
|
nikneem2005 wrote:
I cannot find what's really meant here
Sorry to state the obvious, but what is really meant is what it really says. The "Method" you are calling is actually a constructor (similar in signiture to a method). As the error states, there is no constructor which takes one parameter (argument).
You can confirm this by opening object browser in VS, navigating to system.data.sqlclient.SqlException - it has NO public constructors at all. The most likely reason for this is that SqlException was not intended to be used by client code. A quick look with .NET reflector confirms there is a serialization constructor on this object only.
Now, to answer your question, create your own exception, inheriting from System.ApplicationException, and throw this instead. Something like "ConfigurationException" would be relevant in this case and could be reused anytime where the app is not configured correctly.
|
|
|
|
General 
News 
Suggestion 
Question 
Bug 
Answer 
Joke 
Praise 
Rant 
Admin 
Submit an article or tip
