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Consider the following code example
class Program
{
static void Main(string[] args)
{
StudentInfo stud = new StudentInfo();
stud.Name.FirstName = "zai";
stud.name.FirstName = "zai";
}
}
class NameInfo :ICloneable
{
private string firstname;
public string FirstName
{
get { return firstname; }
set { firstname = value; }
}
public object Clone()
{
NameInfo n = new NameInfo();
n.LastName = this.lastname;
return n;
}
}
class StudentInfo:ICloneable
{
public NameInfo name = new NameInfo();
public NameInfo Name
{
get
{
if (name != null)
return (NameInfo)name.Clone();
else
return null;
}
set
{
if (value != null)
name = (NameInfo)value.Clone();
else
name = null;
}
}
public object Clone()
{
StudentInfo s = new StudentInfo();
s.Name = this.Name;
return s;
}
}the following statement fails when accessing firstname thru Name property
stud.Name.FirstName = "zai";
while the one below is ok
stud.name.FirstName = "zai";
why??
if I was not using an IClonable interface both of them work....but im not sure its an IClonable issue...
is there any rule that says that we souldnt access inner variables through a property of that object?
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stud.Name.FirstName = "zai"; doesn't work because of the getter for the Name property. There you clone the field name and return this newly created instance. Afterwards you assign a new first name to the clone instance, which cannot reflect in the field of your StudentInfo instance as your operating on another instance of Nameinfo.
So if you clone a field inside a getter before returning it, you actually protect it from be changed by any outside code.
"Programming today is a race between software engineers striving to build bigger and better idiot-proof programs, and the Universe trying to produce bigger and better idiots. So far, the Universe is winning." - Rick Cook www.troschuetz.de
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Hi. I'm developing a client application that sends xml files as DIME attachments to a web service. I use WSE 2.0 for that.
In order to fix some bugs it is almost imperative to me to see how the whole SOAP request looks like(the SOAP envelope and the attachmets), and also the SOAP response from the server.
I did some research and found out that WSE 3.0 has just such a feature, to write incoming and outgoing SOAP messages to trace files on the disk. But unfortunatelly I am forced to use WSE 2.0 because the web service can only handle DIME attachments and WSE 3.0 has no support for DIME.
So, what other ways are there to view the SOAP request/response contents?
Any ideea would be greatly apreaciated.
Thanks.
LATER EDIT: It turns out that WSE 2.0 also has this tracing facility, but I can't use it because my project must also use WSE 3.0 and even though references to both Microsoft.Web.Services2 and Microsoft.Web.Services3 are added to my Visual Studio 2005 Project if I right click the project name in Solution Explorer, at the bottom of the context menu I only have "WSE 3.0 Settings" (no WSE 2.0 whatsoever).
Is there any way to get the SOAP request context programatically using some of the classes in WSE?
What can I say... Life is complex and has so many aspects.
-- modified at 2:25 Wednesday 10th January, 2007
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Hi,
In Windows Application .Net2.0.
if i create a form object.
so how to check form object created or not .
arrgent.
Thannks
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How do you mean ? If it's been shown, or if the class exists ?
Christian Graus - C++ MVP
'Why don't we jump on a fad that hasn't already been widely discredited ?' - Dilbert
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iam working in c# 2005
i have mdi form when i try to open child form in it it's open in maxmizied state instead of i chane it's properites to windows state=maxmizied
and in the form load i write this code
"this.WindowState = FormWindowState.Maximized;"
notes
the form right to left =yes "it's client requirement" even if i chane this properites the same problem occurred
what is the soulations ?!!!!!!!
ma_refay
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I'm not sure of what you're asking. You can set the initial state in the properties in the designer.
Christian Graus - C++ MVP
'Why don't we jump on a fad that hasn't already been widely discredited ?' - Dilbert
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i initial state form windows state in the properties in the designer but it's execute it it's take the size when apper in the desgin view not maxmizied it even if i set it's properites in designer
ma_refay
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Hello!
I am having a problem with .net remoting.
I have searched Microsoft documents, but got no hints.
When the server is accessed by remote client, it turns to be proxy : OK
All instances <b>new inside the server class</b> stay native--direct call : OK
All references <b>passed to the server class</b> turns to be TransparentProxy : Why ? Is it because the reference is outside the server object memory segment ? But they are in the same app domain--real object out there.
Technically,
<code>
class Server : MarshalByRefObject {
ListBox myList = new ListBox(); // stay native--direct call
ListBox hisList; // turns to TransparentProxy
public Server(ListBox list) {
hisList=list;
... // open port, listen to client request
}
}
class MyForm : System.Windows.Form {
public MyForm() {
...
new Server(listBox); // start the server
}
}
</code>
Your comments would be very helpful. Thanks.
Sovann
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When you start a file conversion process in iTunes (programatically, through the COM interface), it hands you back a status object. You can poll that status object for progress data, or you can create event handlers and that object will raise progress events for you. Hence:
iTunesConvertOperationStatus itcoStatus = null;<br />
...<br />
<br />
itcoStatus = iTunesApp.ConvertFile2(strPath);<br />
...<br />
<br />
itcoStatus.OnConvertOperationCompleteEvent +=new (shortened)_OnConvertOperationCompleteEventEventHandler(itcoStatus_OnConvertOperationCompleteEvent);
My question is: once I've bound the event handler to the instance of the object, can I call:
itcoStatus = iTunesApp.ConvertFile2(strPath)
over and over without first releasing the handler? Or do I have to wait for the Complete event, release the handler, call ConvertFile2(), and rebind the handler each time?
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As long as the iTunesApp object is instantiated and you don't create a new instance of it each time, the event handler will stay bound until you release it.
-----------------------------
In just two days, tomorrow will be yesterday.
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do you mean the itcoStatus object? The event handlers (in this case) aren't bound to the iTunesApp object.
Which bring up my point: if I simply keep overwriting the itcoStatus object with a new instance (not explicitly releasing the old instance) are the handlers bound to the new instance? Or did they become defunct when the old instance was stomped?
I realize my terms aren't very technical here, which reveals my real lack of knowledge about "instances"...
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JoeRip wrote: do you mean the itcoStatus object?
Yes, I did mean the itcoStatus object. I guess I wasn't paying close enough attention to your example code.
JoeRip wrote: if I simply keep overwriting the itcoStatus object with a new instance (not explicitly releasing the old instance) are the handlers bound to the new instance? Or did they become defunct when the old instance was stomped?
Yes, if you overwrite the existing instance of the object with a new instance (by repeatedly calling itcoStatus = new iTunesConvertOperationStatus() you will loose the event handlers. Each time you call new you are creating an entirely new instance of the object.
In your example code, the first line:
iTunesConvertOperationStatus itcoStatus = null;
defines a variable named itcoStatus whose data type is a itunesConvertOperationsStatus object. When you then run code like this:
itcoStatus = new iTunesConvertOperationStatus()
you create a specific instance of that object in memory. The itcoStatus variable holds a reference (essentially a pointer) to the memory used by that instance. Each time you call new you get a new instance, which means you potentially get a different portion of memory so the itcoStatus variable ends up with a different reference.
-----------------------------
In just two days, tomorrow will be yesterday.
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Dear all ,
i am making web application using C#, asp.net2.0(visual studio 2005) and sql2000, i want to know how can i securly pass password value from
client to server. PLease guide me.
Thanks
regards
imran khan
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There is no 100% secure way. You should never pass the password around anyway, compare its hash value. There are plenty of resources here and elsewhere that cover this.
only two letters away from being an asset
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do a search for terms like "challenge response" "salted hash" the subject is very complex and you should read as much as you can before implementing a solution as very subtle changes in the way you implement things make massive differences to security.
HTH
Russ
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I want to get the error number when a exception occurs and i catch using the try {.. } catch {..} method.
i hav given like
catch { Exception ex}
{
}
but i didnt find any property of ex that gives me error number
Please help
REgards
Hari
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Exceptions are string messages. You need something like ex.Message which gives the text message of the exception. Hope this helps you 
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There is no error number. .NET uses exceptions instead of error codes, with good reason. The exception defines the error, why return a code which, you hope, the user can turn back into an Exception so that it contains meaningful error. No code can give a call stack - it's a step backwards.
Christian Graus - Microsoft MVP - C++
Metal Musings - Rex and my new metal blog
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Yes, but I think he means he wants to differentiate between specific exceptions, so he can decide how to handle them programatically. In other words, how do you compare exceptions?
I've wondered this myself.
For almost any method or property in .NET, you can look at the help files and see what possible Exceptions they can throw. So it stands to reason that you can somehow say "if myException is X, do this" somehow.
I suppose you could compare the message text, but I doubt this is canonical, guaranteed to be unique or not change...
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I'm a newb, but it looks like you have to know what exceptions can be thrown, and handle it in one of two ways:
try
{
DoWork();
}
catch (System.File.FileNotExists e)
{
}
OR,
catch (Exception e)
{
if (e is StackOverflowException ||
e is OutOfMemoryException)
DoSomething();
}
of course, you don't want to eat all exceptions, as I am in the second example. That will screw you.
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JoeRip wrote: how do you compare exceptions?
You don't really compare exceptions. If you need to take different action based on different exceptions, you would write multiple catch handlers.
try
{
}
catch (System.NullReferenceException)
{
}
catch (System.InvalidOperationException)
{
}
The only caution is that you need to pay attention to the ordering of the catch handlers. The runtime will go through the catch handlers until it finds the first one that can handle the exception and then stop. This means that if you catch a base exception before a derived one, you will never handle the derived exception. For example:
try
{
}
catch (System.ArgumentException)
{
}
catch (System.ArgumentNullException)
{
}
try
{
}
catch (System.ArgumentNullException)
{
}
catch (System.ArgumentException)
{
}
In general, you only want to catch exceptions that your code can actually do something about and perform some sort of cleanup. You don't want to use them to help control your program flow as actually catching the exception is expensive.
-----------------------------
In just two days, tomorrow will be yesterday.
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JoeRip wrote: So it stands to reason that you can somehow say "if myException is X, do this" somehow.
You can catch Exception and use the 'is' keyword, ( and hopefully rethrow if it's unhandled ), or you can specify in your catch statemetns what you wan to catch ( better ) Some exceptions have base classes, which you can also catch.
Christian Graus - C++ MVP
'Why don't we jump on a fad that hasn't already been widely discredited ?' - Dilbert
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try
{
// throw specific exception here
}
catch ( KeyNotFoundException ex )
{
}
catch ( InvalidOperationException ex )
{
}
catch ( Exception ex )
{
// all unhandled exceptions go here
}
HTH,
Martin
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Hello, I'm fairly new to the C# world. What am I saying? I'm pretty new to coding all around and I've ran into a problem I have had to luck figuring out. So...
Before you ask, yes I have looked threw articles on the site. But none of them really help me. It is very hard to understand uncommented code at my skill level so it really does no good to me.
My first C# application is a simple RSS reader. I have most of the stuff done for it besides the TreeView. I cannot seem to figure out how to get this TreeView to grab data from my database and then display it in a certain way.
The tree view in the end should look like this:
<br />
TreeView<br />
<br />
|Folder<br />
|-RSS Channel/Feed<br />
|--News Item<br />
Ok so I have three folders in my database: Folders, Feeds, and NewsItems. The folders in the tree view will call the database table Folders, the rss channels/feed will call data from the Feeds table and finally the news items will call data from the NewsItems table.
How would I go about doing this? I have predefined values in all tables in the database, I'm not worried about adding new stuff to it yet and have it update. I just need to get the view to work.
Thanks for any help you can give
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