RE: Re: HttpWebRequest in Silverlight Application [Solved] - WPF Discussion Boards

HttpWebRequest in Silverlight Application

3-Dec-09 6:38

javixuwi wrote:
And the codebehind too?

Yes. There's no difference between the code-behind code and
the code produced from XAML Smile | :)

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

Message Removed

2-Dec-09 3:56

N_tro_P

2-Dec-09 3:56

Message Removed

Thi**012-Dec-09 3:20

Thi**01

2-Dec-09 3:20

Hi, this is my first post in this forum. Codeproject is a good source for nearly everything i need. Big Grin | :-D

I use Visual Studio 2008 SP1 and have Silverlight 3.
I made: new project -> C# -> Silverlight Application

I have to read a xml-file and i wanted to use the XmlReader-class:

XmlReader xmlReader = XmlReader.Create(@"C:\Dokumente und Einstellungen\THI\Desktop\stage2.xml");

An Exception occured: file is not in the xap-package try to use fetching the file with HttpWebRequest. (something like this)

I tryed to make this example work:
http://msdn.microsoft.com/en-us/library/system.net.httpwebrequest(VS.95).aspx#Mtps_DropDownFilterText[^]

I dont understand how to write the RequestState class and i dont understand what is: allDone.WaitOne() or allDone.Set()

Is here anybody who can explain this?

I tried to write RequestState class:

public class RequestState : IAsyncResult
    {

        private HttpWebRequest myRequest = null;

        public HttpWebRequest Request
        {
            get { return myRequest; }
            set { myRequest = value; }
        }


        private HttpWebResponse myResponse = null;

        public HttpWebResponse Response
        {
            get { return myResponse; }
            set { myResponse = value; }
        }


        private Stream myStream = null;

        public Stream StreamResponse
        {
            get { return myStream; }
            set { myStream = value; }
        }

        private byte[] ReadBuffer = new byte[1024];

        public byte[] ReBuffer
        {
            get { return ReadBuffer; }
            set { ReadBuffer = value; }
        }

        private StringBuilder myStringBuilder = new StringBuilder();

        public StringBuilder RequestData
        {
            get { return myStringBuilder; }
            set { myStringBuilder = value; }
        
        }
    }

Greetings
Thi

Re: HttpWebRequest in Silverlight Application

Mark Salsbery2-Dec-09 8:51

Re: HttpWebRequest in Silverlight Application

2-Dec-09 8:51

First - your URI @"C:\Dokumente und Einstellungen\THI\Desktop\stage2.xml"
is not going to work. Silverlight runs on the client and does not allow
direct access to the client's file system without asking the user first,
using the OpenFileDialog class.

The XmlReader.Create() method that takes a URI string only works for files
packaged in the Silverlight application's XAP file.

If the XML file you need to open is on the client's computer, you
need to use OpenFileDialog, not HttpWebRequest.

So where is the XML file you need to load?

Thi**01 wrote:
I dont understand how to write the RequestState class and i dont understand what is: allDone.WaitOne() or allDone.Set()

All web requests in Silverlight are asynchronous. That means
the request is sent, processing continues, and at some later time
when a reply is received, the app is notified.

The example code you linked to uses an EventWaitHandle to wait
on the requesting thread until the reply is received, then continues
processing, essentially making the web request synchronous. IMO
it's a bad example - a reply could take many seconds, so if the
request is made on the UI thread, you've halted the UI thread,
which could lead to a bad user experience.

allDone is an EventWaitHandle or one of its derived classes, so if
you're new to threading, you may want to look at that documentation.

The RequestState can be anything you want - an existing object of any
class. Its purpose is to allow you to pass something across the asynchrounous
call. Whatever object you pass in the request will be available to you in the
reply.

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

Abhinav S2-Dec-09 23:44

Re: HttpWebRequest in Silverlight Application

2-Dec-09 23:44

As another way to load an xml file dynamically from the server, you could use the OpenReadCompleted() or DownloadStringCompleted() method of the WebClient class. This method loads the xml file asynchronously - http://blogs.silverlight.net/blogs/msnow/archive/2009/02/10/silverlight-tip-of-the-day-93-reading-xml-with-silverlight.aspx[^]

Hope this helps.

Thi**013-Dec-09 1:29

Thi**01

3-Dec-09 1:29

Thanks, im at work now and going to try your tips, then i post again!

RE: Re: HttpWebRequest in Silverlight Application [Solved]

Thi**013-Dec-09 6:53

Thi**01

3-Dec-09 6:53

The tip with the WebClient worked for me. Big Grin | :-D

I will explain what the point was.

You have to know this:
http://msdn.microsoft.com/en-us/library/cc645032(VS.95).aspx[^]

What this text says is, that the Silverlight-Runtime looks first for a certain security-file when a resource is called from a server: the clientaccesspolicy.xml. When this file is not correct or not there at all then a security exception is thrown.

The problem was:
This file was not there so i had to put i manually on my localhost.
(I have apache. The clientaccesspolicy.xml has to be put in the htdocs folder.)
clientaccesspolicy.xml :

<?xml version="1.0" encoding="utf-8"?>
<access-policy>
  <cross-domain-access>
    <policy>
      <allow-from>      
        <domain uri="*"/>
      </allow-from>      
      <grant-to>      
        <resource path="/" include-subpaths="true"/>
      </grant-to>      
    </policy>
  </cross-domain-access>
</access-policy>

This is my Silverlight App :

public void client_DownloadStringCompleted(object sender, DownloadStringCompletedEventArgs e)
        {
                Debug.WriteLine(e.Result);
        }

        public void XmlReadTest()
        {
            Uri url = new Uri("http://localhost/stage2.xml",UriKind.Absolute);
            WebClient client = new WebClient();
            client.DownloadStringCompleted += new DownloadStringCompletedEventHandler(client_DownloadStringCompleted);
            client.DownloadStringAsync(url);
          
        }

Nice Closing Time

Executes a delegate on the thread that owns the control's underlying window handle

cppwxwidgetsss2-Dec-09 2:41

cppwxwidgetsss

2-Dec-09 2:41

Hi I want to use this lovely code in a WPF app
but there is no Invoke method for WPF's TextBox
so I have a run time error which say that the SerialPort's Thread is trying to change the TextBox that owns to another thread
anybody have any idea?
here is the code(article), I am talking about:
http://www.codeproject.com/KB/cs/virtualports.aspx?msg=3291065#xx3291065xx

Re: Executes a delegate on the thread that owns the control's underlying window handle

Ian Shlasko2-Dec-09 5:06

Ian Shlasko

2-Dec-09 5:06

The Invoke method in WPF was moved to the Dispatcher object, which can be accessed via the Dispatcher property on the TextBox.

Proud to have finally moved to the A-Ark. Which one are you in?
Author of Guardians of Xen (Sci-Fi/Fantasy novel)

Re: Executes a delegate on the thread that owns the control's underlying window handle

cppwxwidgetsss2-Dec-09 18:23

cppwxwidgetsss

2-Dec-09 18:23

thank you very much
I was really confused

MenuItem like the Sort menuitem in Firefox 3's Organize Bookmarks ... ?

Mohammad Dayyan1-Dec-09 23:01

Mohammad Dayyan

1-Dec-09 23:01

Hi.
I'm gonna create a MenuItem like this one in Firefox 3's Organize Bookmarks ... [^] in WPF !

Could you please guide me how I should do it ?
Thanks.

Re: MenuItem like the Sort menuitem in Firefox 3's Organize Bookmarks ... ?

Ashfield2-Dec-09 1:32

Ashfield

2-Dec-09 1:32

Mohammad Dayyan wrote:
I'm gonna create a MenuItem like

Kind of conflicts with

Mohammad Dayyan wrote:
Could you please guide me how I should do it ?

doesn't it?

Try, when you have a specific problem post your code and someone will probably help

Bob
Ashfield Consultants Ltd
Proud to be a 2009 Code Project MVP

Should I use Silverlight

Mycroft Holmes1-Dec-09 19:26

Mycroft Holmes

1-Dec-09 19:26

I have a mate who has had a web site built for him, based on C# and classic ASP, it is all very amateurish and I am considering offering to rebuild the thing properly. This will be a labour of love, or at least a few beers anyway. The design requires a lot of pictures/graphics but is predominately a data driven site.

I have no experience at all with WPF and Silverlight although I have started working through a book and I have built a number of ASPX sites. Also I am a lousy UI designer, I'm the great proponent of battleshit grey.

So, should I use it to learn Silverlight or just stick to ASPX. Professionally I am a winforms LOB developer so there will be limited professional benefit.

Never underestimate the power of human stupidity
RAH

Re: Should I use Silverlight

Mark Salsbery2-Dec-09 8:28

Re: Should I use Silverlight

2-Dec-09 8:28

There's a significant learning curve if you're new
to WPF/Silverlight, although since you know .NET
already, it lessens the pain a bit.

Unlike ASP/ASP.NET, Silverlight apps run on the client. This allows
for much richer user experience on the client end that you can't get
from static HTML pages, and you get to use familiar language like C#/VB.NET.
When Silverlight is hosted in an ASP.NET web app, you can
then have processes running on both the server and the client.
If that is something you can (or need to) leverage to make
the site better and the learning curve is worth the time,
then go for it.

Otherwise, I would think ASP.NET would be a good option.

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

Mycroft Holmes2-Dec-09 12:05

Mycroft Holmes

2-Dec-09 12:05

It turns out there are mild time constraints so I may save the SL for version 2. Thanks for your input Mark

Never underestimate the power of human stupidity
RAH

WPF Data Grid Auto Height problem

wasimsharp30-Nov-09 21:44

wasimsharp

30-Nov-09 21:44

hi friends i use wpf Datagrid.

<br />
 <Custom:DataGrid  VirtualizingStackPanel.IsVirtualizing="True" VirtualizingStackPanel.VirtualizationMode="Recycling" EnableRowVirtualization="True"   SelectionUnit="FullRow" RowBackground="Aqua" AlternatingRowBackground="Beige"   IsReadOnly="True"  SelectionMode="Extended" AutoGenerateColumns="False"   Background="White" FontWeight="Bold" FontFamily="Arial" FontSize="10.667" Height="Auto"  x:Name="dgChronicDiagnosis" HorizontalGridLinesBrush="{x:Null}" VerticalScrollBarVisibility="Auto"    MinHeight="0"  VerticalGridLinesBrush="{x:Null}" GridLinesVisibility="None" RowDetailsVisibilityMode="Collapsed"   BorderBrush="{x:Null}" ColumnHeaderStyle="{DynamicResource DataGridColumnHeaderStyle}" RowStyle="{DynamicResource DataGridRowStyle1}" BorderThickness="0"  Margin="0,4,0,0" VerticalAlignment="Center" VerticalContentAlignment="Stretch" IsSynchronizedWithCurrentItem="True" AreRowDetailsFrozen="True"><br />
                        <Custom:DataGrid.Columns><br />
<br />
											<br />
			<Custom:DataGridTemplateColumn  Header="OnSet" Width="10*"  CellStyle="{DynamicResource TempDataGridCellStyle}" ><br />
								<Custom:DataGridTemplateColumn.CellTemplate><br />
									<DataTemplate ><br />
										<TextBlock Text="{Binding ONSET}"    FontFamily="Arial" FontSize="10.667"/><br />
									</DataTemplate><br />
								</Custom:DataGridTemplateColumn.CellTemplate><br />
							</Custom:DataGridTemplateColumn><br />
							<br />
						</Custom:DataGrid.Columns><br />
					</Custom:DataGrid><br />

Now when i bind the Data grid with list having one record there i lot of white space as record increases the space also increases

WANTED wasim khan(Killed 50 Innocent Buggs, Distroyed 200 Exception, make 5 Project Hostage) any Compnay Hire him will pay 30,000. Best place where u can get him is Sorcim Technologies Murre Road RWP

Re: WPF Data Grid Auto Height problem

Super Lloyd2-Dec-09 14:43

Super Lloyd

2-Dec-09 14:43

You might have more luck on their own forum!
http://wpf.codeplex.com/Thread/List.aspx[^]

[Message Deleted]

noufal200930-Nov-09 21:05

noufal2009

30-Nov-09 21:05

[Message Deleted]

Abhinav S30-Nov-09 21:57

30-Nov-09 21:57

If your application uses Silverlight 3, you can make use of NotifyOnValidationError with your validation being implemented in the setter property. Have a look here - http://blogs.silverlight.net/blogs/jesseliberty/archive/2009/07/18/what-s-new-in-silverlight-3-validation.aspx[^]

noufal200930-Nov-09 23:08

noufal2009

30-Nov-09 23:08

I can't get u Abinav.Could you just give me the code.Thanks

Abhinav S30-Nov-09 23:15

30-Nov-09 23:15

This website has a code sample - http://mtaulty.com/CommunityServer/blogs/mike_taultys_blog/archive/2009/03/18/a-quick-look-at-silverlight-3-data-validation.aspx[^]

Re: textbox validation in silverlight [modified]

noufal200930-Nov-09 23:35

noufal2009

30-Nov-09 23:35

Sample is fine.But,it wont find out if u enter numerics in text column.I need the entire code for that.When I click the button,it should check the values in textboxes and it should display.Could u help me?thanks

Abhinav S30-Nov-09 23:45

30-Nov-09 23:45

Try using something like int32.TryParse() in the setter property -
http://www.bloggingdeveloper.com/post/Int32Parse-ConvertToInt32-Int32TryParse-Comparing-String-to-Integer-Conversion-Methods-of-NET.aspx[^]

modified on Tuesday, December 1, 2009 7:57 AM

Mark Salsbery1-Dec-09 8:08