Re: Push data from WCF to client - C# Discussion Boards

Re: Push data from WCF to client

BobJanova28-Feb-12 22:29

BobJanova

28-Feb-12 22:29

nitin_ion wrote:
Is there a way we can use WCF to push data to clients over HTTP?

There is no way to push over HTTP full stop, never mind with WCF. HTTP is based on a request/response model so you can only send data in response to a request made by the client.

Re: Push data from WCF to client

Pete O'Hanlon28-Feb-12 23:27

Pete O'Hanlon

28-Feb-12 23:27

That's not entirely correct. It is possible to establish a polling duplex HTTP connection. You can find details here[^] on HTTP push.

*pre-emptive celebratory nipple tassle jiggle* - Sean Ewington

"Mind bleach! Send me mind bleach!" - Nagy Vilmos

My blog | My articles | MoXAML PowerToys | Mole 2010 - debugging made easier - my favourite utility

Re: Push data from WCF to client

BobJanova29-Feb-12 1:55

BobJanova

29-Feb-12 1:55

Most of those are essentially faking a push. Re-using a connection would count but I didn't think the browser/service client would accept a second response within the same connection if it hadn't requested it.

Re: Push data from WCF to client

Pete O'Hanlon29-Feb-12 2:02

Pete O'Hanlon

29-Feb-12 2:02

And this is why I was careful to say a Duplex connection - so that the client knows that the response will be left open.

*pre-emptive celebratory nipple tassle jiggle* - Sean Ewington

"Mind bleach! Send me mind bleach!" - Nagy Vilmos

My blog | My articles | MoXAML PowerToys | Mole 2010 - debugging made easier - my favourite utility

Re: Push data from WCF to client

PIEBALDconsult29-Feb-12 2:41

PIEBALDconsult

29-Feb-12 2:41

Push is evil, don't use it.

Always use polling.

Re: Push data from WCF to client

jschell29-Feb-12 11:47

jschell

29-Feb-12 11:47

Yep.

And like extra worse for a chat mobile application.

Re: Push data from WCF to client

BobJanova1-Mar-12 1:47

BobJanova

1-Mar-12 1:47

For a web service, yes. There are other scenarios where that's definitely not the case though (when the speed of update to clients is critical and the number of clients relatively low).

Re: Push data from WCF to client

jschell1-Mar-12 8:43

jschell

1-Mar-12 8:43

BobJanova wrote:
There are other scenarios ...

Never for a "chat" service. That means humans. And with a low number even less point.

C# programme crashes without an obvious reason

Ash Zidan28-Feb-12 6:16

Ash Zidan

28-Feb-12 6:16

I'm writing a C# program that reads RSS feeds and displays them on a windows form... The program first worked fine, no problem, but suddenly it began to crash once I had navigated in the web browser control in the C# program. I got into some sort of knowing what causes the problem... When provide the web browser using WebBrowser.DocumentText = sting with large amount of data it does crash... so does anybody have a solution for that??

sb.Append("");
sb.Append(row.title);
sb.Append("

");
sb.Append(ASCIIEncoding.ASCII.GetString((byte[])row.desc));
desc_self_nav = false;
webBrsrRSSDesc.DocumentText = sb.ToString()

Re: C# programme crashes without an obvious reason

Eddy Vluggen28-Feb-12 9:13

Eddy Vluggen

28-Feb-12 9:13

Is it the webbrowser that crashes, or the stringbuilder? Can you paste the text of the exception that it throws?

Bastard Programmer from Hell Suspicious | :suss:

Re: C# programme crashes without an obvious reason

Shameel28-Feb-12 18:32

Shameel

28-Feb-12 18:32

Eddy Vluggen wrote:
Is it the webbrowser that crashes, or the stringbuilder?

That's what the OP wants to know.

Eddy Vluggen wrote:
Can you paste the text of the exception that it throws?

Obviously, if there was an exception, it would not be called a crash.

Re: C# programme crashes without an obvious reason

Eddy Vluggen28-Feb-12 20:27

Eddy Vluggen

28-Feb-12 20:27

Shameel wrote:
That's what the OP wants to know

Not so hard to find out, is it? Just put the contents of the StringBuilder in a (temp) string, and assign it to the browser on the second line.

Shameel wrote:

Obviously, if there was an exception, it would not be called a crash.

Thanks for the useful hint Smile | :)

Bastard Programmer from Hell Suspicious | :suss:

Re: C# programme crashes without an obvious reason

Pete O'Hanlon28-Feb-12 21:29

Pete O'Hanlon

28-Feb-12 21:29

Shameel wrote:
Obviously, if there was an exception, it would not be called a crash.

Not true. If he hasn't handled the exception it would still crash, but there would still be an exception.

*pre-emptive celebratory nipple tassle jiggle* - Sean Ewington

"Mind bleach! Send me mind bleach!" - Nagy Vilmos

My blog | My articles | MoXAML PowerToys | Mole 2010 - debugging made easier - my favourite utility

Re: C# programme crashes without an obvious reason

Shameel28-Feb-12 23:10

Shameel

28-Feb-12 23:10

Pete O'Hanlon wrote:
but there would still be an exception.

Correct, but in case of a crash, the OP would not be able to post the exception here, and that is what I was pointing out to.

Re: C# programme crashes without an obvious reason

Pete O'Hanlon28-Feb-12 23:22

Pete O'Hanlon

28-Feb-12 23:22

I'm pretty sure that an unhandled exception would be written to the event log if it crashed an application. It's been so long since I've written an application where I didn't have a top level exception handler, but I'm fairly certain this is the case.

*pre-emptive celebratory nipple tassle jiggle* - Sean Ewington

"Mind bleach! Send me mind bleach!" - Nagy Vilmos

My blog | My articles | MoXAML PowerToys | Mole 2010 - debugging made easier - my favourite utility

Re: C# programme crashes without an obvious reason

Eddy Vluggen29-Feb-12 0:30

Eddy Vluggen

29-Feb-12 0:30

Non curo; if he's working with computers, then he should be able to tell a bit more than "it crashed". Your basic helpdesk-employee will tell you that there are different kind of crashes - should I simply assume that it generated a BSOD?

Most people here are referring to "exceptions" when they're talking about code and "crash".

Bastard Programmer from Hell Suspicious | :suss:

Re: C# programme crashes without an obvious reason

jschell28-Feb-12 13:52

jschell

28-Feb-12 13:52

Ash Zidan wrote:
but suddenly it began to crash once

And that means what exactly?

What exactly is the evidence that you see?

Re: C# programme crashes without an obvious reason

Shameel28-Feb-12 23:15

Shameel

28-Feb-12 23:15

Try storing the content of the StringBuilder to a temporary html file and use WebBrowser.Navigate method to load the file. This will help you in isolating the real culprit - the StringBuilder or the WebBrowser.

PropertyDescriptor.GetValue and PropertyInfo.GetValue

kashme28-Feb-12 3:23

kashme

28-Feb-12 3:23

PropertyDescriptor.GetValue(object component);
what is this component. I do not get. Can someone please get an example.
Also why PropertyInfo.GetValue(object, objects[]) needs to have parameters. Why we cannot have values through reflection directly. Can someone give me example of propertydescriptor.GetValue(object component), how to use it. I do not find much on msdn.

Re: PropertyDescriptor.GetValue and PropertyInfo.GetValue

Eddy Vluggen28-Feb-12 9:01

Eddy Vluggen

28-Feb-12 9:01

kashme wrote:
what is this component

It's an abstract description of a property[^].

kashme wrote:
Can someone please get an example

At the bottom of that page are the usual examples.

Used it for example, when implementing a GetProperties[^] method. A neat way to provide properties that a PropertyEditor can understand while passing an array wrapped in a ICustomTypeDescriptor[^].

Bastard Programmer from Hell Suspicious | :suss:

MOQ unit test

michaelgr128-Feb-12 2:50

michaelgr1

28-Feb-12 2:50

Hello,

I am writing unit test to a method named methodName for example. The tested class extends another base class.

The tested method uses a method that is implemented in the base class, But i want to use Mock in order to Mock this method.

How can i do it?

Re: MOQ unit test

Eddy Vluggen28-Feb-12 9:10

Eddy Vluggen

28-Feb-12 9:10

Something like this;

    class MyBaseClass
    {
        public virtual string methodName()
        {
            return "This is base calling";
        }
    }
    class MyTestedClass: MyBaseClass
    {
        public override string methodName()
        {
            return "This is the testing value calling";
        }

    }
    class MyTestedClassMock: MyBaseClass
    {
        public override string methodName()
        {
            return "Whaahaha, I'm not the real one, just a mock-stand in.";
        }
    }

//..in the test-bit
MyBaseClass someObject = new MyTestedClassMock();
                        // or new MyTestedClass();
MessageBox.Show(someObject.methodName());

Bastard Programmer from Hell Suspicious | :suss:

Accessing System Databases

AmbiguousName28-Feb-12 1:48

AmbiguousName

28-Feb-12 1:48

hello guys... How can I access system databases in which <b>The Machine</b> stores some of the info we can use it. For example <b>Win32_OperatingSystem</b>. Now I can access 'LastBootUpTime' from this database.
The question is:
how can find and view this database (and other related databases) in sql server? thnx for any input

Re: Accessing System Databases

Bernhard Hiller28-Feb-12 3:25

Bernhard Hiller

28-Feb-12 3:25

That's Windows Management Instrumentation (WMI). See e.g. http://msdn.microsoft.com/en-us/library/windows/desktop/aa393964(v=vs.85).aspx[^]

Synchronize RichTextBox scrolling

lune1228-Feb-12 0:57

lune12

28-Feb-12 0:57

Hi,

I have two multiline RichTextBoxes, no wrap (horizontal/vertical scrollbars)

Is there a way I can sync the scrolling so when I scroll one, the other one scrolls?

Thanks

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