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hi.good day.just would like to ask..how can i save something into an image file(into jpg etc.) that is in the child form?thnx!
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Well, I don't know what the problem is...
Search MSDN for Bitmap class and have a look at its methods...
Q:What does the derived class in C# tell to it's parent?
A:All your base are belong to us!
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hi,
how can i track the downloading of images from web browser control used in my application,i used begindownload event but i couldn't get the url of the image,
thanks.
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Is there anyway to get or reference the local directory a web service is located in ?
i.e. similar to Application.StartupPath ?
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A web service is a variant of an ASP.NET weg application. It doesn't "come alive" until it's called by some consumer and instantiated. There is no "StartupPath".. You could look into using Server.MapPath(), but web services are not my strong suit.
RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome
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Right, I need to get the local path reference within the service during runtime, so I'm not worried about it not being instantiated. I'll look into MapPath(), thanks.
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Well it appears the Server.GetPath() method is useful from a client perspective, but I need to get the local path in the service. Any other suggestions ?
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I was wrong...just had to pass null as the path...thanks Dave.
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RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome
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 Can a windows service capture HID input events?
I need to capture HID input from a remote control. I have done this and was successful in a windows application by overriding WndProc.
I need to be able to do this in a service and can't seem to get anything? Does a service have a hidden top level window I can override? Is there a way to do this?
Mary
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Hey,
i am trying to develop a small program taking advantage of .NET Remoting.
I have a button which i want to Start and Stop the Server with.
But my problem is that I cant really find any information about how to stop the Server.
I simply start the Server by doing the following:
RemotingConfiguration.Configure("theconfiguration.config");
But then i dont know how to stop the Server again when pushing the button.
Can anyone help me ?
I can see that if i instead of using a configuration file, set it all up directly in the code there is the ChannelServices.RegisterChannel and the ChannelServices.UnregisterChannel.
But will this be the correct way to do it if i want to start and stop the Server ?
Or will i have to etc. make a new application domain and run the server there and then destroy it when i want the Server to stop ?
How should it be done ?
Hope someone can help me
Best regards
Martin
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I am trying to sort out the difference between these terms as they seem to be thrown around interchangebly. But indeed are they really different concepts or is casting basically helpful in describing boxing/unboxing?
Casting defined: objects of one type converted to objects of another type
Boxing defined: 1 - casting a value type into a reference type 2 - casting to an object
Unboxing: casting the reference type back into a value type
And sort of a separate question, but how can I figure out the rules of casting.... in other words I expected to able to do this. Is the reason it cannot be done because the variable i2 is not an object?
int i2 = 5;
string s2 = "";
s2 = (string)i2;
However you can do this, and myShort is not an object.
short myShort;
int myInt = 500;
myShort = (short)myInt;
So I am a bit confused about when I can try to cast vs box!
-- modified at 21:04 Saturday 28th January, 2006
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Boxing is casting a value type to a reference type.
Unboxing is just the reverse.
You want to avoid boxing whenever possible. There is a HUGE performance penalty for both box and unboxing.
An integer, or just about snything else for that matter, can't be cast to a string. Each type has it's own .ToString() method to return a string representation of the object.
int i2 =5;
string s2 = i2.ToString();
Value types CAN be cast to other values types. All that's required is a little change in the representation. Your example works because a short (16-singed integer) can be converted to an int (32-bit signed integer, just by widening the field. There's no loss of data.
Are there any hard and fast rules to casting? No, not really. It depends on the type and what it's being converted to.
RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome
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Regarding my terminology question... It seems like boxing is a specific way of casting (casting value type to reference type)? I just seem to find the two terms thrown around a lot and I want to make sure I am using them correctly.
I think I am getting the point of why I could not cast s2 = int(i2) ?? But to be sure, this is my take after reading responses: (Very simply put however!)....Basically string and int types are derived from the same parent class, so I cannot cast. Instead if I need to do the casting (correct term?), then I do this in C# by using the ToString method ( and in the background C# boxes the value (i.e. makes it an object )).
I hit the books and found various definitions for boxing/unboxing and only one definition for casting. But it never really helped me to know why I could not cast an int to a string. So thank-you for the help. It seems like some of the casting can be trial and error and the compiler in most cases will help you out; but if you care to look at the where the classes are coming from (the parent class) then you can figure out if the cast might work?
Various definitions of boxing (choose your favorite one  )
1) Boxing: So that common operations can be performed on both reference types and value types, each value type has a corresponding hidden reference type. This is created when it is cast to a reference type. This process is called boxing.
2) Boxing: Value types are allocated on the stack by default, but they can always be converted into a heap-based reference-type object, called boxing.
3) Unboxing: The reverse of boxing is of course unboxing, which means that you can convert a heap-based reference-type object into its value-type equivalent…
4) Boxing and unboxing are the processes that enable value types (e.g., integers) to be treated as reference types (objects). The value is "boxed" inside an Object, and subsequently "unboxed" back to a value type.
5) Boxing At its simplest, boxing is the conversion of a value type to a reference type. The reciprocal case is when a reference type is unboxed back to a value type.
6) Boxing: Thus, a value type is “boxed” inside an object (when an object reference refers to a value type, a process know as boxing occurs).
Casting Definitions
Casting: Object of one type can be converted to objects of another type… It can be implicit or explicit.
-- modified at 13:43 Sunday 29th January, 2006
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LuluSailor wrote: It seems like boxing is a specific way of casting (casting value type to reference type)?
No, it's not. Look at the term itself - BOXING. What your doing is pretty close to putting a type in a box so that it can be contained and manipulated as the box type, not the type that's in the box.
Casting is a conversion of a type to another, SIMILAR, type. That's why you can't cast an int to a string. They're nowhere near similar in their functionality.
RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome
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First let's look at the two different kinds of data types:
Value type: A simple data type that is stored as-is, like an int.
Reference type: A pointer (which is basically an int) that points to memory allocated on the heap, that contains the actual data.
Casting reference types in .NET is somewhat different than in most other platforms. The objects in .NET contains their own datatype information, so the type of the reference only determines how you use the object, not the actual type of the object. This means that in .NET you can only cast a reference to the actual class or one of its base classes, not to some completely different class.
Then let's look at the different ways of casting:
:: Casting a value type to another value type. Most numeric value types can be casted to other numeric value types. This is actually more of a conversion than a cast.
:: Casting an object to any of its base classes, for an example casting an HtmlButton to an Object. This only changes the type of the reference, leaving the actual data unchanged.
:: Casting an object from a base class to the actual class or one of the inherited classes on the way, for an example casting an Object reference that points to an actual HtmlButton object from Object to HtmlControl.
:: Boxing a value type into a reference type, for an example casting an int to an Object. This will allocate memory on the heap where an object structure containing the int is stored, and the result is an Object reference that points to that memory structure.
:: Unboxing a reference type to its value type, for an example casting from an Object to an int. This will retrieve the data from the memory structure and release the memory used on the heap. Unboxing can only be done to the exact value type that the object contains, no other value type.
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Hello all,
I have search a loooooooot in Google to get a nice neat way to convert MS Word Document into plain text file using C#. I did not get any solution. It would be great if anyone can help me with any snippet or suggession.
Thanks to all
Emran
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Check out wvWare library .wv is a library which allows access to Microsoft Word files. It can load and parse Word 2000, 97, 95 and 6 file formats.
Use wvText - to convert word document to plain text.
http://wvware.sourceforge.net[^]
DevIntelligence.com - My blog for .Net Developers
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Thank you sooooo much.
Emran
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Hi all ,
I have a byte array which includes ascii data.
What is the best way to transfer it to hex ?
By the way , How can I show this data within datagrid ?
Thanks very much
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I am trying to write a simple class, my own CheckBox using my own "bitmap checkmarks", derived from UserControl. I want to add this to my Toolbox and use it in windows forms applications. Not only do I need to understand how to properly write this, I also need to know how to properly embed the bitmap resources in the control.
Can anyone direct me to a good tutorial?
Thanks!
Mark
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I should check if user’s mail exists or not, when she/he enters in my web application. But in asp.net we can just send an email with classes in the System.web.mail namespace. But as I mentioned, it is vital in my web application that user’s mail is a real mail. So I should check it if it is real or not (except its format).
Please instruct me to solve my problem with mail checking.
Thanks a lot.
Thanks Rastegar
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There is no way that you can automatically check for certain if the mail address exists.
You can ask the mail server if it will accept the mail address, but that is not a guarantee that the address is correct. Large mail servers (for an example hotmail) will accept any address, as it's too much work to check the address both before and after recieving a mail.
The only way that you can be certain that the address works is if you send a mail to the user, that contains an address where they can confirm the address.
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