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What Suzanne said is a good idea. If you want columnar data, however, take a look at Multi-Column ComboBox[^] here on CP. It should give you some ideas and seems to already be data-bindable.
Microsoft MVP, Visual C#
My Articles
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Hi,
I'd like to write a simple program that starts by itself when the computers is starting, without user intervention.
How can I do that ?
Thanks
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You can just drop the program in your startup folder if your running windows.
C:\Documents and Settings\user\Start Menu\Programs is a typical location of the startup folder.
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Yes, that's an idea; but it's not what I expected.
In fact, I want to write an underground program, running like an anti-virus or an alarm. Suppose, to make simple, that it is an alarm.
When the computer is turning on, the alarm-program is starting (undergroundly). And each hour, it makes a sound (with no interface).
How can I do that. Must I build a Windows service ?
Thanks
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That would be your best bet. Unless you want to start your program from the Run key in the Registry and set your forms ShowInTaskBar property to false.
RageInTheMachine9532
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bsargos wrote:
undergroundly
I learned me a knew werd to day!
---------------------------
He who knows that enough is enough will always have enough.
-Lao Tsu
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It's not funny 
I would prefer you answer my question !
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You'll have to create a windows service. If you're using VS.NET you can create a new project by selecting Windows Service to get you started. You'll need to add your code to the OnStart and OnStop methods in the class it creates for you. From the design view of the class right click and select Add Installer. This makes it possible to use installutil.exe to install the service on the target machine. Read about Windows Service Applications[^] for more information.
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Thank you very much
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I've just copied the sample DataGridTimePickerColumn style from the VS help, and used it on a few DateTime columns in a DataGrid (in the constructor, I set it to the short date format). What a mess! You'd have to pay people a lot of money to make them use it!!
Pressing 'Tab' seems to move across the columns as expected, until after you click on one of the columns to give it focus. Then 'Tab' takes you to every other column! Plus if the DateTimePicker is on a form, you can use the up and down arrow keys to scroll the parts of the (short) date. In the DataGrid, all they do is move up and down the columns of the grid.
Has anyone seen an example anywhere showing how to do this properly?
Roj
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The keyword is example. There are several implementations of various DataGridColumnStyle derivates here on CodeProject and on MSDN[^], but you could always read the documentation and create your own.
The arrow keys are intepreted differently because of the control being hosted in the DataGrid. It's not so easy to make these behave as you'd expect for the hosted control - in this case a DateTimePicker.
Microsoft MVP, Visual C#
My Articles
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hi
i want to know that there is three loops for matrix multipltication for instance
for(i=0;i<3;i++)
{
for (j=0;j<3;j++)
{
for(k=0;k<3;k++)
know if i want to know abt how i should enter the value in an array and what is the function of theird loop how should i input the value in array
3*3d matrix
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If you're declaring a multi-dimensional array (as opposed to a jagged array), then you could do something like this:
double[,,] matrix = new double[3,3,3];
for (int i = 0; i < 3; i++)
for (int j = 0; j < 3; j++)
for (int k = 0; k < 3; k++)
matrix[i, j, k] = i * j * k; A jagged array wouldn't be a whole lot different, but you'd declare it as double[][][] and reference elements as matrix[i][j][k]. A multi-dimensional array is recommended in this case. You can read more information about the difference by reading about Arrays[^] in the C# Language Specification.
Microsoft MVP, Visual C#
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hi
i try to send xml bitween client and server win app
but
i want to do that as xml not by encoding it into byte`s
thank you
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You must. All web servers do it, whether download HTML web pages or sending and receiving SOAP messages. You must encode it (whether you do it or some class you use does it, like an HttpWebClientProtocol used for web service proxies or a simple HttpWebRequest) and use the same encoding on both the client and server.
Once the server decodes it using the correct encoding, you've got your XML back. This is how a network works - you upload/download bytes and text gets encoded in order to be send as bytes. Most often, APIs do this for you, but it still gets done. If you insist on using socket connections and sending data yourself instead of using one of the many helper classes, then you are responsible for encoding and decoding data.
Microsoft MVP, Visual C#
My Articles
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Hi,
How can I drawing on axhost control?
I try this code: (AxHost Control is a)
Graphics g = a.CreateGraphics();
Pen p = new Pen(Color.Blue,2);
g.DrawLine(p,0,0,100,100);
but line dont appear. Thanks.
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An AxHost control is just the base class for a hosted ActiveX control. The ActiveX control is responsible for it's own drawing, so using a Graphics object to draw on top of it won't work unless you provide some way through your controls supported interfaces to draw on it. One such way would be to return an HDC (as an IntPtr in managed code) from some method in your ActiveX control that you can use to create a Graphics object (see Graphics.FromHdc) and then draw on the ActiveX control.
Also, be sure to call Dispose on your Graphics object to free native resources that the Graphics object uses, otherwise your performance will degrade over time.
Microsoft MVP, Visual C#
My Articles
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good day everyone,
can someone help me figure out how to get a list of all machines on specified network domain?
thanks a lot.
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If you're using Active Directory for your domain, you can use the DirectorySearcher. See the article Querying Active Directory using .NET Classes and LDAP Queries[^] for an example.
If you're not using an Active Directory for your domain but instead are using old-school NT4 domains, then you'll have to query the WINS server. I'm not aware of any examples doing this, but you could find more information about querying a WINS server in the MSDN Library[^].
Microsoft MVP, Visual C#
My Articles
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:-Ohay there,
Before getting into any solution please read the entire message. See we have Exception Class in .net framework from (System.Object). Exception class is the base class for all exceptions(this sentence is from msdn).
So you are agreeing with this concept that, Exception is a Class.
just see the eg:
1. int a=10,b=20;
2. try
3. {
4. a=b/a;
5. }
6. catch(Exception Ex)
7. {
8. MessageBox.Show(Ex.Message.ToString());
9. }
Ok we can fight.
Before fighting the above mentioned eg won't rise any errors. Ok. Here my duty is something else.
If you see the line 6.
catch(Exception Ex) here I am just creating a variable of the type Exception. On line 8. I am calling a Property of the Exception class without creating the instance of Exception. Only initialization is happed in line 6.
How can I call a property of a class without creating an instance of that class ?
Any concept is there like " static property " ? Up to my level best No.
Just think you have different idea on the above mentioned question. Then what Microsoft mean by the signature of Property "Message" in Exception Class.
public virtual string Message {get;}
the above confusion is there for all properties which is available in Exception Class.
One more scenario If I create an instance of Exception class I will get all properties and method which available for the line 8.
What is this ?
Here what is the point creating instance if we want.
Next doubt is about disposing.
I think we can dispose instances of any class. What about the dispose method for an exception class ?
Just think I am creating one instance of Exception class (ins1).
How GC will destruct the inc1. When it destruct ?
Advance thanks for you
Sreejith SS Nair
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Line 6 does create a variable of type Exception. The piece you're missing is that the framework's exception handling takes the object that was thrown using throw and tries to match it up with the exception handlers. If your handler is the one that's called, the Ex reference is set to the object that was thrown (which is either of type Exception or some type derived from Exception). Your line 8 is then using the instance property Message (which is already a string, no need for ToString) of the object that was thrown.
You can have static properties on a class; you simply use the static keyword just as you would for fields or methods.
You can only call the Dispose method on objects whose class implements a Dispose method. The convention is that exception objects do not implement a Dispose method, because it would be hard for generic code to know that Dispose should be called.
Stability. What an interesting concept. -- Chris Maunder
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sreejith ss nair wrote:
So you are agreeing with this concept that, Exception is a Class
I don't need to agree with it. It is fact. I could disagree until I was blue in the face, but it would remain a fact that Exception is a class.
sreejith ss nair wrote:
How can I call a property of a class without creating an instance of that class ?
You can't the C# compiler won't allow it. You are confusing the fact that you don't see the object being created. In this example you do:
1: try
2: {
3: throw(new Exception())
4: }
5: catch(Exception ex)
6: {
7: Console.WriteLine(ex.Message);
8: }
sreejith ss nair wrote:
I think we can dispose instances of any class. What about the dispose method for an exception class ?
Just think I am creating one instance of Exception class (ins1).
How GC will destruct the inc1. When it destruct ?
Like all objects in the .NET Framework - When the garbage collector chooses to. It is a non-deterministic function so you cannot determine when it is destroyed.
"You can have everything in life you want if you will just help enough other people get what they want." --Zig Ziglar
Coming soon: The Second EuroCPian Event
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sreejith ss nair wrote:
Just think you have different idea on the above mentioned question. Then what Microsoft mean by the signature of Property "Message" in Exception Class.
public virtual string Message {get;}
the above confusion is there for all properties which is available in Exception Class.
A virtual or abstract member can be overridden by a derivative class, so that if you a derivative class was actually thrown and overrides the Message property, then its Message property's get accessor is called, not that on the Exception class. This is polymorphism, something you really need to understand if you're doing object-oriented development.
See Virtual Methods[^] in the C# Language Specification for more information.
Microsoft MVP, Visual C#
My Articles
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Hi,
I have 2 methods exported from a dll, MyReader.dll
typedef unsigned short UINT16;
typedef unsigned int UINT32;
typedef unsigned char UINT8;
#define CMYREADER_API __declspec(dllexport)
class CMYREADER_API CMyReader
{
public:
bool mapImage(UINT16 SectorSize, const char * FileOnHardDriveToMap);
bool mapImage(UINT16 SectorSize, bool (* CallbackFunctionAddress)(UINT32 SectorToBeRead, UINT8 * SetToSectorData, bool IsLiteral));
....
};
How can I call the 2nd method from My C# Client? I have declared a delegate to pass as the 2nd argument to the function.
[DllImport("MyReader.dll", EntryPoint ="?mapImage@CMYReader@@QAE_NGP6A_NIPAE_N@Z@Z",CallingConvention=CallingConvention.ThisCall)]
private static extern System.Int32 mapImage(IntPtr inst,System.UInt16 SectorSize, ReadSectorDelegate CallbackFunctionAddress);
But when I give the CallingConvention as CallingConvention.ThisCall, I get the following error.
---------------------------<br />
Microsoft Visual C++ Debug Library<br />
---------------------------<br />
Debug Error!<br />
<br />
Program: E:\Vini\MyRdrTest\bin\Debug\MyRdrTest.exe<br />
Module: <br />
File: i386\chkesp.c<br />
Line: 42<br />
The value of ESP was not properly saved across a function call. This is usually a result of calling a function declared with one calling convention with a function pointer declared with a different calling convention. <br />
<br />
(Press Retry to debug the application)<br />
---------------------------<br />
Abort Retry Ignore <br />
---------------------------
But if I change the callingConvention to CallingConvention.StdCall, it does not call the CallBack function. Is there any other way to implement this? What am I doing wrong here?
Kindly help.
Vini
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