Search Results

Search found 4334 results on 174 pages for 'sender'.

Page 20/174 | < Previous Page | 16 17 18 19 20 21 22 23 24 25 26 27  | Next Page >

• how to display numbers without garbage numbers?

  - by Medeti Naveen Kumar

  Hi friends, whenever i press the numbers in text filed upto 9 numbers my textfield has taken right values but i press 10 th number.i have found duplicate number. in my header file i declare a pressnumber is "long long int" -(IBAction)press:(id)sender{ pressNumber = pressNumber*10 + (int)[sender tag]; phonenumber.text = [NSString stringWithFormat:@"%d",currentNumber]; } i want to enter a phone number in my textfiled but it is not taken 10 right numbers. Thanking you,

  Read the article

• Unable to find assembly, C#

  - by PlasmaCube

  So, here's the deal. I've got two ASP.NET applications, both of which use SQLServer Session State management. They also both use the same server. I've got a custom session class in an external DLL, which fully implements serialization, and which both applications have referenced. Each application, in turn, has a class which inherits from the DLL class, and both applications use their own respective classes for their session state. Now, what I was trying to accomplish was that if you wanted to go to the other application, it could look in the session (they all use the same session key) and treat the existing object there as the base (the one from the DLL), extract whatever login info you need, then overwrite the session object with your own. Unfortunately, when the second application attempts to read the session, it seems that it looks for the DLL of the first application, and when it can't find it, it throws an exception. Is there a flaw in my logic? Here's an example: // Global.asax of the 1st app protected void Session_Start(object sender, EventArgs e) { Session.Add( "UserSessionKey", new FirstUserSession()); // FirstUserSession inherits from BaseUserSession } Now the second application: // Global.asax of 2nd app protected void Session_Start(object sender, EventArgs e) { if (Session["UserSessionKey"] != null) { BaseUserSession existing = (BaseUserSession)Session["UserSessionKey"]; SecondUserSession session = new SecondUserSession(); // This also inherits from BaseUserSession session.Authenticated = existing.Authenticated; session.Id = existing.Id; session.Role = existing.Role; Session.Add("UserSessionKey", session); } else { Session.Add("UserSessionKey", new SecondUserSession()); } } Here's the exception stack trace. In this case, "MyCBC" is the real name of the first app, and "ASPTesting" is the second app. [SerializationException: Unable to find assembly 'MyCBC, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null'.] System.Runtime.Serialization.Formatters.Binary.BinaryAssemblyInfo.GetAssembly() +1871092 System.Runtime.Serialization.Formatters.Binary.ObjectReader.GetType(BinaryAssemblyInfo assemblyInfo, String name) +7545734 System.Runtime.Serialization.Formatters.Binary.ObjectMap..ctor(String objectName, String[] memberNames, BinaryTypeEnum[] binaryTypeEnumA, Object[] typeInformationA, Int32[] memberAssemIds, ObjectReader objectReader, Int32 objectId, BinaryAssemblyInfo assemblyInfo, SizedArray assemIdToAssemblyTable) +120 System.Runtime.Serialization.Formatters.Binary.ObjectMap.Create(String name, String[] memberNames, BinaryTypeEnum[] binaryTypeEnumA, Object[] typeInformationA, Int32[] memberAssemIds, ObjectReader objectReader, Int32 objectId, BinaryAssemblyInfo assemblyInfo, SizedArray assemIdToAssemblyTable) +52 System.Runtime.Serialization.Formatters.Binary.__BinaryParser.ReadObjectWithMapTyped(BinaryObjectWithMapTyped record) +190 System.Runtime.Serialization.Formatters.Binary.__BinaryParser.ReadObjectWithMapTyped(BinaryHeaderEnum binaryHeaderEnum) +61 System.Runtime.Serialization.Formatters.Binary.__BinaryParser.Run() +253 System.Runtime.Serialization.Formatters.Binary.ObjectReader.Deserialize(HeaderHandler handler, __BinaryParser serParser, Boolean fCheck, Boolean isCrossAppDomain, IMethodCallMessage methodCallMessage) +168 System.Runtime.Serialization.Formatters.Binary.BinaryFormatter.Deserialize(Stream serializationStream, HeaderHandler handler, Boolean fCheck, Boolean isCrossAppDomain, IMethodCallMessage methodCallMessage) +203 System.Web.Util.AltSerialization.ReadValueFromStream(BinaryReader reader) +788 System.Web.SessionState.SessionStateItemCollection.ReadValueFromStreamWithAssert() +55 System.Web.SessionState.SessionStateItemCollection.DeserializeItem(String name, Boolean check) +281 System.Web.SessionState.SessionStateItemCollection.get_Item(String name) +19 System.Web.SessionState.HttpSessionStateContainer.get_Item(String name) +13 System.Web.SessionState.HttpSessionState.get_Item(String name) +13 ASPTesting._Default.Page_Load(Object sender, EventArgs e) in C:\Documents and Settings\sarsstu\My Documents\Projects\Testing\ASPTesting\ASPTesting\Default.aspx.cs:20 System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o, Object t, EventArgs e) +14 System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e) +35 System.Web.UI.Control.OnLoad(EventArgs e) +99 System.Web.UI.Control.LoadRecursive() +50 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +627 Thanks to everyone in advance.

  Read the article

• error prepareForSegue between a viewController and a tableViewController

  - by beta

  -(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender { if ([segue.identifier isEqualToString:@"My_TableView"]) { MyTableViewController *destViewController = segue.destinationViewController; destViewController.data = data; } } Hi, I have a problem doing a segue (modal) between a ViewController to a TableViewController. The name of the segue between the ViewController and the NavigationController is "My_TableView". Compiler gives me this error: unrecognized selector sent to instance 0x9275b50 what's the problem?

  Read the article

• Error exposing event througt interface

  - by carlos

  I have this interface Interface IProDataSource Delegate Sub DstartingHandler(ByVal sender As Object, ByVal e As EventArgs) Event starting_Sinc As DstartingHandler End Interface Trying to use the intarce like this Public Class DataSource : Implements IProDataSource Public Event starting_Sinc As DstartingHandler Implements IProDataSource.starting_Sinc Public Delegate Sub DstartingHandler(ByVal sender As Object, ByVal e As EventArgs) End Class Gives me the next error Event 'starting_Sinc' cannot implement event 'starting_Sinc' on interface 'IProDataSource' because their delegate types 'DstartingHandler' and 'IProDataSource.DstartingHandler' do not match.

  Read the article

• how to find out which textbox is currenlty selected.

  - by abcdefghijklmnopqrstuvwxyz

  I have 3 text-boxes, how do I find out which text-box is currently selected (has focus). I am unable to come up with anything. Public Class Form1 Public activeTextBox As TextBox = CType(Me.ActiveControl, TextBox) Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click activeTextBox.Text = activeTextBox.Text & "This is text 1" End Sub Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click activeTextBox.Text = activeTextBox.Text & "This is the text 2" End Sub End Class

  Read the article

• Disable automatic index on related object id from yml

  - by BugBusterX

  Doctrine Automatically creates indexes on columns that are used to define object relations, For example user: id, name message: id, sender_id, receiver_id, message if I define relationship between message and user in a way that message has one Sender and has one Receiver, doctrine will automatically index sender_id and receiver_id fields when I generate sql from model. I would like to disable index on sender, because I manually create index with sender_id and receiver id together. How can I disable auto generated index?

  Read the article

• SQL Server 2008 Problem with SCOPE_IDENTITY()

  - by jinsungy

  My code does not update the thread field. It is null. Anyone have any ideas? INSERT INTO [Messages]([Sender], [Receiver], [Job_Number], [Subject], [MessageText], [DateSent]) VALUES(@Sender, @Receiver, @Job_Number, @Subject, @MessageText, @DateSent) SET @ThreadID = SCOPE_IDENTITY() UPDATE [Messages] SET Thread = @ThreadID WHERE MessageID = @ThreadID

  Read the article

• MKMapView maptype not changing!

  - by TheLearner

  I cannot understand why my MKMapView does not want to change to satellite view. This method is called and case 1 is called I have stepped over it but it simply does not change to satellite type it always changes to standard. It only works when it goes back to Map type. Anyone have any ideas? - (IBAction)mapSatelliteSegmentControlTapped:(UISegmentedControl *)sender { switch (sender.selectedSegmentIndex) { case 1: //Satellite self.mapView.mapType = MKMapTypeSatellite; default: //Map self.mapView.mapType = MKMapTypeStandard; } }

  Read the article

• copy code from one file to other file in c#

  - by gou

  Using Below Code, We Can Copy Code from One textbox to other textbox. private void Copybtn_Click(object sender, EventArgs e) { Clipboard.SetText(txtSour.Text); } //paste the text private void Pastebtn_Click(object sender, EventArgs e) { txtDestinatio.Text = Clipboard.GetText(); } My Requirement is: Copy Code from one file to other file using C#? Is It possible using ClipBoard? Then i need to copy code from one file to other? Please AnyOne Help me

  Read the article

• [C#] Get Index of Control in an Control-Array

  - by Cocaine112358

  I have a TextBox Array private TextBox[,] Fields = new TextBox[9, 9]; and all the TextBoxes have got the same TextChanged-Event void Field_Changed( object sender, EventArgs e ) Is there a way to get the Index of the sender in the Array (without giving each TextBox it's own EventHandler)?

  Read the article

• a string doesn't exist in the current context

  - by Strider007

  the following is a part of my code. string lsStatus; lsStatus = ((Tv10DBLookup)(Sender)).EditValue.ToString(); while im debuging the code, im getting the following: "lsStatus is not in the context" ! Knowing that (Tv10DBLookup)(Sender)).EditValue is returning the value "Closed" what does this mean ?

  Read the article

• Passing parameters between Silverlight and ASP.NET – Part 1

  - by mohanbrij

  While working with Silverlight applications, we may face some scenarios where we may need to embed Silverlight as a component, like for e.g in Sharepoint Webpars or simple we can have the same with ASP.NET. The biggest challenge comes when we have to pass the parameters from ASP.NET to Silverlight components or back from Silverlight to ASP.NET. We have lots of ways we can do this, like using InitParams, QueryStrings, using HTML objects in Silverlight, etc. All these different techniques have some advantages or disadvantages or limitations. Lets see one by one why we should choose one and what are the ways to achieve the same. 1. InitParams: Lets start with InitParams, Start your Visual Studio 2010 IDE, and Create a Silverlight Application, give any name. Now go to the ASP.NET WebProject which is used to Host the Silverlight XAP component. You will find lots of different tags are used by Silverlight object as <params> tags. To use InitParams, Silverlight provides us with a tag called InitParams which we can use to pass parameters to Silverlight object from ASP.NET. 1: <object data="data:application/x-silverlight-2," type="application/x-silverlight-2" width="100%" height="100%"> 2: <param name="source" value="ClientBin/SilverlightApp.xap"/> 3: <param name="onError" value="onSilverlightError" /> 4: <param name="background" value="white" /> 5: <param name="minRuntimeVersion" value="4.0.50826.0" /> 6: <param name="initparams" id="initParams" runat="server" value=""/> 7: <param name="autoUpgrade" value="true" /> 8: <a href="http://go.microsoft.com/fwlink/?LinkID=149156&v=4.0.50826.0" style="text-decoration:none"> 9: <img src="http://go.microsoft.com/fwlink/?LinkId=161376" alt="Get Microsoft Silverlight" style="border-style:none"/> 10: </a> 11: </object> Here in the code above I have included a initParam as a param tag (line 6), now in the page load I will add a line 1: initParams.Attributes.Add("value", "key1=Brij, key2=Mohan"); This basically add a value parameter inside the initParam. So thats all we need in our ASP.NET side, now coming to the Silverlight Code open the code behind of App.xaml and add the following lines of code. 1: private string firstKey, secondKey; 2: private void Application_Startup(object sender, StartupEventArgs e) 3: { 4: if (e.InitParams.ContainsKey("key1")) 5: this.firstKey = e.InitParams["key1"]; 6: if (e.InitParams.ContainsKey("key2")) 7: this.secondKey = e.InitParams["key2"]; 8: this.RootVisual = new MainPage(firstKey, secondKey); 9: } This code fetch the init params and pass it to our MainPage.xaml constructor, in the MainPage.xaml we can use these variables according to our requirement, here in this example I am simply displaying the variables in a Message Box. 1: public MainPage(string param1, string param2) 2: { 3: InitializeComponent(); 4: MessageBox.Show("Welcome, " + param1 + " " + param2); 5: } This will give you a sample output as Limitations: Depending on the browsers you have some limitation on the overall string length of the parameters you can pass. To get more details on this limitation, you can refer to this link :http://www.boutell.com/newfaq/misc/urllength.html 2. QueryStrings To show this example I am taking the scenario where we have a default.aspx page and we are going to the SIlverlightTestPage.aspx, and we have to work with the parameters which was passed by default.aspx in the SilverlightTestPage.aspx Silverlight Component. So first I will add a new page in my application which contains a button with ID =btnNext, and on click of the button I will redirect my page to my SilverlightTestAppPage.aspx with the required query strings. Code of Default.aspx 1: protected void btnNext_Click(object sender, EventArgs e) 2: { 3: Response.Redirect("~/SilverlightAppTestPage.aspx?FName=Brij" + "&LName=Mohan"); 4: } Code of MainPage.xaml.cs 1: public partial class MainPage : UserControl 2: { 3: public MainPage() 4: { 5: InitializeComponent(); 6: this.Loaded += new RoutedEventHandler(MainPage_Loaded); 7: } 8: 9: void MainPage_Loaded(object sender, RoutedEventArgs e) 10: { 11: IDictionary<string, string> qString = HtmlPage.Document.QueryString; 12: string firstName = string.Empty; 13: string lastName = string.Empty; 14: foreach (KeyValuePair<string, string> keyValuePair in qString) 15: { 16: string key = keyValuePair.Key; 17: string value = keyValuePair.Value; 18: if (key == "FName") 19: firstName = value; 20: else if (key == "LName") 21: lastName = value; 22: } 23: MessageBox.Show("Welcome, " + firstName + " " + lastName); 24: } 25: } Set the Startup page as Default.aspx, now run the application. This will give you the following output: Since here also you are using the Query Strings to pass your parameters, so you are depending on the browser capabilities of the length of the query strings it can pass. Here also you can refer the limitation which I have mentioned in my previous example for the length of parameters you can use.   3. Using HtmlPage.Document Silverlight to ASP.NET <—> ASP.NET to Silverlight: To show this I setup a sample Silverlight Application with Buttons Get Data and Set Data with the Data Text Box. In ASP.NET page I kep a TextBox to Show how the values passed to and From Silverlight to ASP.NET reflects back. My page with Silverlight control looks like this. When I Say Get Data it pulls the data from ASP.NET to Silverlight Control Text Box, and When I say Set data it basically Set the Value from Silverlight Control TextBox to ASP.NET TextBox. Now let see the code how it is doing. This is my ASP.NET Source Code. Here I have just created a TextBox named : txtData 1: <body> 2: <form id="form1" runat="server" style="height:100%"> 3: <div id="silverlightControlHost"> 4: ASP.NET TextBox: <input type="text" runat="server" id="txtData" value="Some Data" /> 5: <object data="data:application/x-silverlight-2," type="application/x-silverlight-2" width="100%" height="100%"> 6: <param name="source" value="ClientBin/SilverlightApplication1.xap"/> 7: <param name="onError" value="onSilverlightError" /> 8: <param name="background" value="white" /> 9: <param name="minRuntimeVersion" value="4.0.50826.0" /> 10: <param name="autoUpgrade" value="true" /> 11: <a href="http://go.microsoft.com/fwlink/?LinkID=149156&v=4.0.50826.0" style="text-decoration:none"> 12: <img src="http://go.microsoft.com/fwlink/?LinkId=161376" alt="Get Microsoft Silverlight" style="border-style:none"/> 13: </a> 14: </object><iframe id="_sl_historyFrame" style="visibility:hidden;height:0px;width:0px;border:0px"></iframe> 15: </div> 16: </form> 17: </body> My actual logic for getting and setting the data lies in my Silverlight Control, this is my XAML code with TextBox and Buttons. 1: <Grid x:Name="LayoutRoot" Background="White" Height="100" Width="450" VerticalAlignment="Top"> 2: <Grid.ColumnDefinitions> 3: <ColumnDefinition Width="110" /> 4: <ColumnDefinition Width="110" /> 5: <ColumnDefinition Width="110" /> 6: <ColumnDefinition Width="110" /> 7: </Grid.ColumnDefinitions> 8: <TextBlock Text="Silverlight Text Box: " Grid.Column="0" VerticalAlignment="Center"></TextBlock> 9: <TextBox x:Name="DataText" Width="100" Grid.Column="1" Height="20"></TextBox> 10: <Button x:Name="GetData" Width="100" Click="GetData_Click" Grid.Column="2" Height="30" Content="Get Data"></Button> 11: <Button x:Name="SetData" Width="100" Click="SetData_Click" Grid.Column="3" Height="30" Content="Set Data"></Button> 12: </Grid> Now we have to write few lines of Button Events for Get Data and Set Data which basically make use of Windows.System.Browser namespace. 1: private void GetData_Click(object sender, RoutedEventArgs e) 2: { 3: DataText.Text = HtmlPage.Document.GetElementById("txtData").GetProperty("value").ToString(); 4: } 5:  6: private void SetData_Click(object sender, RoutedEventArgs e) 7: { 8: HtmlPage.Document.GetElementById("txtData").SetProperty("value", DataText.Text); 9: } That’s it so when we run this application my Form will look like this. 4. Using Object Serialization. This is a useful when we want to pass Objects of Data from our ASP.NET application to Silverlight Controls and back. This technique basically uses the above technique I mentioned in Pint 3 above. Since this itself is a length topic so details of this I am going to cover in Part 2 of this Post with Sample Code Example very soon.

  Read the article

• Windows Phone 7: Building a simple dictionary web client

  - by TechTwaddle

  Like I mentioned in this post a while back, I came across a dictionary web service called Aonaware that serves up word definitions from various dictionaries and is really easy to use. The services page on their website, http://services.aonaware.com/DictService/DictService.asmx, lists all the operations that are supported by the dictionary service. Here they are, Word Dictionary Web Service The following operations are supported. For a formal definition, please review the Service Description. Define Define given word, returning definitions from all dictionaries DefineInDict Define given word, returning definitions from specified dictionary DictionaryInfo Show information about the specified dictionary DictionaryList Returns a list of available dictionaries DictionaryListExtended Returns a list of advanced dictionaries (e.g. translating dictionaries) Match Look for matching words in all dictionaries using the given strategy MatchInDict Look for matching words in the specified dictionary using the given strategy ServerInfo Show remote server information StrategyList Return list of all available strategies on the server Follow the links above to get more information on each API. In this post we will be building a simple windows phone 7 client which uses this service to get word definitions for words entered by the user. The application will also allow the user to select a dictionary from all the available ones and look up the word definition in that dictionary. So of all the apis above we will be using only two, DictionaryList() to get a list of all supported dictionaries and DefineInDict() to get the word definition from a particular dictionary. Before we get started, a note to you all; I would have liked to implement this application using concepts from data binding, item templates, data templates etc. I have a basic understanding of what they are but, being a beginner, I am not very comfortable with those topics yet so I didn’t use them. I thought I’ll get this version out of the way and maybe in the next version I could give those a try. A somewhat scary mock-up of the what the final application will look like, Select Dictionary is a list picker control from the silverlight toolkit (you need to download and install the toolkit if you haven’t already). Below it is a textbox where the user can enter words to look up and a button beside it to fetch the word definition when clicked. Finally we have a textblock which occupies the remaining area and displays the word definition from the selected dictionary. Create a silverlight application for windows phone 7, AonawareDictionaryClient, and add references to the silverlight toolkit and the web service. From the solution explorer right on References and select Microsoft.Phone.Controls.Toolkit from under the .NET tab, Next, add a reference to the web service. Again right click on References and this time select Add Service Reference In the resulting dialog paste the service url in the Address field and press go, (url –> http://services.aonaware.com/DictService/DictService.asmx) once the service is discovered, provide a name for the NameSpace, in this case I’ve called it AonawareDictionaryService. Press OK. You can now use the classes and functions that are generated in the AonawareDictionaryClient.AonawareDictionaryService namespace. Let’s get the UI done now. In MainPage.xaml add a namespace declaration to use the toolkit controls, xmlns:toolkit="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone.Controls.Toolkit" the content of LayoutRoot is changed as follows, (sorry, no syntax highlighting in this post) <StackPanel x:Name="TitlePanel" Grid.Row="0" Margin="12,5,0,5">     <TextBlock x:Name="ApplicationTitle" Text="AONAWARE DICTIONARY CLIENT" Style="{StaticResource PhoneTextNormalStyle}"/>     <!--<TextBlock x:Name="PageTitle" Text="page name" Margin="9,-7,0,0" Style="{StaticResource PhoneTextTitle1Style}"/>--> </StackPanel> <!--ContentPanel - place additional content here--> <Grid x:Name="ContentPanel" Grid.Row="1" Margin="12,0,12,0">     <Grid.RowDefinitions>         <RowDefinition Height="Auto"/>         <RowDefinition Height="Auto"/>         <RowDefinition Height="*"/>     </Grid.RowDefinitions>     <toolkit:ListPicker Grid.Column="1" x:Name="listPickerDictionaryList"                         Header="Select Dictionary :">     </toolkit:ListPicker>     <Grid Grid.Row="1" Margin="0,5,0,0">         <Grid.ColumnDefinitions>             <ColumnDefinition Width="*"/>             <ColumnDefinition Width="Auto" />         </Grid.ColumnDefinitions>         <TextBox x:Name="txtboxInputWord" Grid.Column="0" GotFocus="OnTextboxInputWordGotFocus" />         <Button x:Name="btnGo" Grid.Column="1" Click="OnButtonGoClick" >             <Button.Content>                 <Image Source="/images/button-go.png"/>             </Button.Content>         </Button>     </Grid>     <ScrollViewer Grid.Row="2" x:Name="scrollViewer">         <TextBlock  Margin="12,5,12,5"  x:Name="txtBlockWordMeaning" HorizontalAlignment="Stretch"                    VerticalAlignment="Stretch" TextWrapping="Wrap"                    FontSize="26" />     </ScrollViewer> </Grid> I have commented out the PageTitle as it occupies too much valuable space, and the ContentPanel is changed to contain three rows. First row contains the list picker control, second row contains the textbox and the button, and the third row contains a textblock within a scroll viewer. The designer will now be showing the final ui, Now go to MainPage.xaml.cs, and add the following namespace declarations, using Microsoft.Phone.Controls; using AonawareDictionaryClient.AonawareDictionaryService; using System.IO.IsolatedStorage; A class called DictServiceSoapClient would have been created for you in the background when you added a reference to the web service. This class functions as a wrapper to the services exported by the web service. All the web service functions that we saw at the start can be access through this class, or more precisely through an object of this class. Create a data member of type DictServiceSoapClient in the Mainpage class, and a function which initializes it, DictServiceSoapClient DictSvcClient = null; private DictServiceSoapClient GetDictServiceSoapClient() {     if (null == DictSvcClient)     {         DictSvcClient = new DictServiceSoapClient();     }     return DictSvcClient; } We have two major tasks remaining. First, when the application loads we need to populate the list picker with all the supported dictionaries and second, when the user enters a word and clicks on the arrow button we need to fetch the word’s meaning. Populating the List Picker In the OnNavigatingTo event of the MainPage, we call the DictionaryList() api. This can also be done in the OnLoading event handler of the MainPage; not sure if one has an advantage over the other. Here’s the code for OnNavigatedTo, protected override void OnNavigatedTo(System.Windows.Navigation.NavigationEventArgs e) {     DictServiceSoapClient client = GetDictServiceSoapClient();     client.DictionaryListCompleted += new EventHandler<DictionaryListCompletedEventArgs>(OnGetDictionaryListCompleted);     client.DictionaryListAsync();     base.OnNavigatedTo(e); } Windows Phone 7 supports only async calls to web services. When we added a reference to the dictionary service, asynchronous versions of all the functions were generated automatically. So in the above function we register a handler to the DictionaryListCompleted event which will occur when the call to DictionaryList() gets a response from the server. Then we call the DictionaryListAsynch() function which is the async version of the DictionaryList() api. The result of this api will be sent to the handler OnGetDictionaryListCompleted(), void OnGetDictionaryListCompleted(object sender, DictionaryListCompletedEventArgs e) {     IsolatedStorageSettings settings = IsolatedStorageSettings.ApplicationSettings;     Dictionary[] listOfDictionaries;     if (e.Error == null)     {         listOfDictionaries = e.Result;         PopulateListPicker(listOfDictionaries, settings);     }     else if (settings.Contains("SavedDictionaryList"))     {         listOfDictionaries = settings["SavedDictionaryList"] as Dictionary[];         PopulateListPicker(listOfDictionaries, settings);     }     else     {         MessageBoxResult res = MessageBox.Show("An error occured while retrieving dictionary list, do you want to try again?", "Error", MessageBoxButton.OKCancel);         if (MessageBoxResult.OK == res)         {             GetDictServiceSoapClient().DictionaryListAsync();         }     }     settings.Save(); } I have used IsolatedStorageSettings to store a few things; the entire dictionary list and the dictionary that is selected when the user exits the application, so that the next time when the user starts the application the current dictionary is set to the last selected value. First we check if the api returned any error, if the error object is null e.Result will contain the list (actually array) of Dictionary type objects. If there was an error, we check the isolated storage settings to see if there is a dictionary list stored from a previous instance of the application and if so, we populate the list picker based on this saved list. Note that in this case there are chances that the dictionary list might be out of date if there have been changes on the server. Finally, if none of these cases are true, we display an error message to the user and try to fetch the list again. PopulateListPicker() is passed the array of Dictionary objects and the settings object as well, void PopulateListPicker(Dictionary[] listOfDictionaries, IsolatedStorageSettings settings) {     listPickerDictionaryList.Items.Clear();     foreach (Dictionary dictionary in listOfDictionaries)     {         listPickerDictionaryList.Items.Add(dictionary.Name);     }     settings["SavedDictionaryList"] = listOfDictionaries;     string savedDictionaryName;     if (settings.Contains("SavedDictionary"))     {         savedDictionaryName = settings["SavedDictionary"] as string;     }     else     {         savedDictionaryName = "WordNet (r) 2.0"; //default dictionary, wordnet     }     foreach (string dictName in listPickerDictionaryList.Items)     {         if (dictName == savedDictionaryName)         {             listPickerDictionaryList.SelectedItem = dictName;             break;         }     }     settings["SavedDictionary"] = listPickerDictionaryList.SelectedItem as string; } We first clear all the items from the list picker, add the dictionary names from the array and then create a key in the settings called SavedDictionaryList and store the dictionary list in it. We then check if there is saved dictionary available from a previous instance, if there is, we set it as the selected item in the list picker. And if not, we set “WordNet ® 2.0” as the default dictionary. Before returning, we save the selected dictionary in the “SavedDictionary” key of the isolated storage settings. Fetching word definitions Getting this part done is very similar to the above code. We get the input word from the textbox, call into DefineInDictAsync() to fetch the definition and when DefineInDictAsync completes, we get the result and display it in the textblock. Here is the handler for the button click, private void OnButtonGoClick(object sender, RoutedEventArgs e) {     txtBlockWordMeaning.Text = "Please wait..";     IsolatedStorageSettings settings = IsolatedStorageSettings.ApplicationSettings;     if (txtboxInputWord.Text.Trim().Length <= 0)     {         MessageBox.Show("Please enter a word in the textbox and press 'Go'");     }     else     {         Dictionary[] listOfDictionaries = settings["SavedDictionaryList"] as Dictionary[];         string selectedDictionary = listPickerDictionaryList.SelectedItem.ToString();         string dictId = "wn"; //default dictionary is wordnet (wn is the dict id)         foreach (Dictionary dict in listOfDictionaries)         {             if (dict.Name == selectedDictionary)             {                 dictId = dict.Id;                 break;             }         }         DictServiceSoapClient client = GetDictServiceSoapClient();         client.DefineInDictCompleted += new EventHandler<DefineInDictCompletedEventArgs>(OnDefineInDictCompleted);         client.DefineInDictAsync(dictId, txtboxInputWord.Text.Trim());     } } We validate the input and then select the dictionary id based on the currently selected dictionary. We need the dictionary id because the api DefineInDict() expects the dictionary identifier and not the dictionary name. We could very well have stored the dictionary id in isolated storage settings too. Again, same as before, we register a event handler for the DefineInDictCompleted event and call the DefineInDictAsync() method passing in the dictionary id and the input word. void OnDefineInDictCompleted(object sender, DefineInDictCompletedEventArgs e) {     WordDefinition wd = e.Result;     scrollViewer.ScrollToVerticalOffset(0.0f);     if (wd.Definitions.Length == 0)     {         txtBlockWordMeaning.Text = String.Format("No definitions were found for '{0}' in '{1}'", txtboxInputWord.Text.Trim(), listPickerDictionaryList.SelectedItem.ToString().Trim());     }     else     {         foreach (Definition def in wd.Definitions)         {             string str = def.WordDefinition;             str = str.Replace("  ", " "); //some formatting             txtBlockWordMeaning.Text = str;         }     } } When the api completes, e.Result will contain a WordDefnition object. This class is also generated in the background while adding the service reference. We check the word definitions within this class to see if any results were returned, if not, we display a message to the user in the textblock. If a definition was found the text on the textblock is set to display the definition of the word. Adding final touches, we now need to save the current dictionary when the application exits. A small but useful thing is selecting the entire word in the input textbox when the user selects it. This makes sure that if the user has looked up a definition for a really long word, he doesn’t have to press ‘clear’ too many times to enter the next word, protected override void OnNavigatingFrom(System.Windows.Navigation.NavigatingCancelEventArgs e) {     IsolatedStorageSettings settings = IsolatedStorageSettings.ApplicationSettings;     settings["SavedDictionary"] = listPickerDictionaryList.SelectedItem as string;     settings.Save();     base.OnNavigatingFrom(e); } private void OnTextboxInputWordGotFocus(object sender, RoutedEventArgs e) {     TextBox txtbox = sender as TextBox;     if (txtbox.Text.Trim().Length > 0)     {         txtbox.SelectionStart = 0;         txtbox.SelectionLength = txtbox.Text.Length;     } } OnNavigatingFrom() is called whenever you navigate away from the MainPage, since our application contains only one page that would mean that it is exiting. I leave you with a short video of the application in action, but before that if you have any suggestions on how to make the code better and improve it please do leave a comment. Until next time…

  Read the article

• Windows Azure Service Bus Splitter and Aggregator

  - by Alan Smith

  This article will cover basic implementations of the Splitter and Aggregator patterns using the Windows Azure Service Bus. The content will be included in the next release of the “Windows Azure Service Bus Developer Guide”, along with some other patterns I am working on. I’ve taken the pattern descriptions from the book “Enterprise Integration Patterns” by Gregor Hohpe. I bought a copy of the book in 2004, and recently dusted it off when I started to look at implementing the patterns on the Windows Azure Service Bus. Gregor has also presented an session in 2011 “Enterprise Integration Patterns: Past, Present and Future” which is well worth a look. I’ll be covering more patterns in the coming weeks, I’m currently working on Wire-Tap and Scatter-Gather. There will no doubt be a section on implementing these patterns in my “SOA, Connectivity and Integration using the Windows Azure Service Bus” course. There are a number of scenarios where a message needs to be divided into a number of sub messages, and also where a number of sub messages need to be combined to form one message. The splitter and aggregator patterns provide a definition of how this can be achieved. This section will focus on the implementation of basic splitter and aggregator patens using the Windows Azure Service Bus direct programming model. In BizTalk Server receive pipelines are typically used to implement the splitter patterns, with sequential convoy orchestrations often used to aggregate messages. In the current release of the Service Bus, there is no functionality in the direct programming model that implements these patterns, so it is up to the developer to implement them in the applications that send and receive messages. Splitter A message splitter takes a message and spits the message into a number of sub messages. As there are different scenarios for how a message can be split into sub messages, message splitters are implemented using different algorithms. The Enterprise Integration Patterns book describes the splatter pattern as follows: How can we process a message if it contains multiple elements, each of which may have to be processed in a different way? Use a Splitter to break out the composite message into a series of individual messages, each containing data related to one item. The Enterprise Integration Patterns website provides a description of the Splitter pattern here. In some scenarios a batch message could be split into the sub messages that are contained in the batch. The splitting of a message could be based on the message type of sub-message, or the trading partner that the sub message is to be sent to. Aggregator An aggregator takes a stream or related messages and combines them together to form one message. The Enterprise Integration Patterns book describes the aggregator pattern as follows: How do we combine the results of individual, but related messages so that they can be processed as a whole? Use a stateful filter, an Aggregator, to collect and store individual messages until a complete set of related messages has been received. Then, the Aggregator publishes a single message distilled from the individual messages. The Enterprise Integration Patterns website provides a description of the Aggregator pattern here. A common example of the need for an aggregator is in scenarios where a stream of messages needs to be combined into a daily batch to be sent to a legacy line-of-business application. The BizTalk Server EDI functionality provides support for batching messages in this way using a sequential convoy orchestration. Scenario The scenario for this implementation of the splitter and aggregator patterns is the sending and receiving of large messages using a Service Bus queue. In the current release, the Windows Azure Service Bus currently supports a maximum message size of 256 KB, with a maximum header size of 64 KB. This leaves a safe maximum body size of 192 KB. The BrokeredMessage class will support messages larger than 256 KB; in fact the Size property is of type long, implying that very large messages may be supported at some point in the future. The 256 KB size restriction is set in the service bus components that are deployed in the Windows Azure data centers. One of the ways of working around this size restriction is to split large messages into a sequence of smaller sub messages in the sending application, send them via a queue, and then reassemble them in the receiving application. This scenario will be used to demonstrate the pattern implementations. Implementation The splitter and aggregator will be used to provide functionality to send and receive large messages over the Windows Azure Service Bus. In order to make the implementations generic and reusable they will be implemented as a class library. The splitter will be implemented in the LargeMessageSender class and the aggregator in the LargeMessageReceiver class. A class diagram showing the two classes is shown below. Implementing the Splitter The splitter will take a large brokered message, and split the messages into a sequence of smaller sub-messages that can be transmitted over the service bus messaging entities. The LargeMessageSender class provides a Send method that takes a large brokered message as a parameter. The implementation of the class is shown below; console output has been added to provide details of the splitting operation. public class LargeMessageSender {     private static int SubMessageBodySize = 192 * 1024;     private QueueClient m_QueueClient;       public LargeMessageSender(QueueClient queueClient)     {         m_QueueClient = queueClient;     }       public void Send(BrokeredMessage message)     {         // Calculate the number of sub messages required.         long messageBodySize = message.Size;         int nrSubMessages = (int)(messageBodySize / SubMessageBodySize);         if (messageBodySize % SubMessageBodySize != 0)         {             nrSubMessages++;         }           // Create a unique session Id.         string sessionId = Guid.NewGuid().ToString();         Console.WriteLine("Message session Id: " + sessionId);         Console.Write("Sending {0} sub-messages", nrSubMessages);           Stream bodyStream = message.GetBody<Stream>();         for (int streamOffest = 0; streamOffest < messageBodySize;             streamOffest += SubMessageBodySize)         {                                     // Get the stream chunk from the large message             long arraySize = (messageBodySize - streamOffest) > SubMessageBodySize                 ? SubMessageBodySize : messageBodySize - streamOffest;             byte[] subMessageBytes = new byte[arraySize];             int result = bodyStream.Read(subMessageBytes, 0, (int)arraySize);             MemoryStream subMessageStream = new MemoryStream(subMessageBytes);               // Create a new message             BrokeredMessage subMessage = new BrokeredMessage(subMessageStream, true);             subMessage.SessionId = sessionId;               // Send the message             m_QueueClient.Send(subMessage);             Console.Write(".");         }         Console.WriteLine("Done!");     }} The LargeMessageSender class is initialized with a QueueClient that is created by the sending application. When the large message is sent, the number of sub messages is calculated based on the size of the body of the large message. A unique session Id is created to allow the sub messages to be sent as a message session, this session Id will be used for correlation in the aggregator. A for loop in then used to create the sequence of sub messages by creating chunks of data from the stream of the large message. The sub messages are then sent to the queue using the QueueClient. As sessions are used to correlate the messages, the queue used for message exchange must be created with the RequiresSession property set to true. Implementing the Aggregator The aggregator will receive the sub messages in the message session that was created by the splitter, and combine them to form a single, large message. The aggregator is implemented in the LargeMessageReceiver class, with a Receive method that returns a BrokeredMessage. The implementation of the class is shown below; console output has been added to provide details of the splitting operation.   public class LargeMessageReceiver {     private QueueClient m_QueueClient;       public LargeMessageReceiver(QueueClient queueClient)     {         m_QueueClient = queueClient;     }       public BrokeredMessage Receive()     {         // Create a memory stream to store the large message body.         MemoryStream largeMessageStream = new MemoryStream();           // Accept a message session from the queue.         MessageSession session = m_QueueClient.AcceptMessageSession();         Console.WriteLine("Message session Id: " + session.SessionId);         Console.Write("Receiving sub messages");           while (true)         {             // Receive a sub message             BrokeredMessage subMessage = session.Receive(TimeSpan.FromSeconds(5));               if (subMessage != null)             {                 // Copy the sub message body to the large message stream.                 Stream subMessageStream = subMessage.GetBody<Stream>();                 subMessageStream.CopyTo(largeMessageStream);                   // Mark the message as complete.                 subMessage.Complete();                 Console.Write(".");             }             else             {                 // The last message in the sequence is our completeness criteria.                 Console.WriteLine("Done!");                 break;             }         }                     // Create an aggregated message from the large message stream.         BrokeredMessage largeMessage = new BrokeredMessage(largeMessageStream, true);         return largeMessage;     } }   The LargeMessageReceiver initialized using a QueueClient that is created by the receiving application. The receive method creates a memory stream that will be used to aggregate the large message body. The AcceptMessageSession method on the QueueClient is then called, which will wait for the first message in a message session to become available on the queue. As the AcceptMessageSession can throw a timeout exception if no message is available on the queue after 60 seconds, a real-world implementation should handle this accordingly. Once the message session as accepted, the sub messages in the session are received, and their message body streams copied to the memory stream. Once all the messages have been received, the memory stream is used to create a large message, that is then returned to the receiving application. Testing the Implementation The splitter and aggregator are tested by creating a message sender and message receiver application. The payload for the large message will be one of the webcast video files from http://www.cloudcasts.net/, the file size is 9,697 KB, well over the 256 KB threshold imposed by the Service Bus. As the splitter and aggregator are implemented in a separate class library, the code used in the sender and receiver console is fairly basic. The implementation of the main method of the sending application is shown below.   static void Main(string[] args) {     // Create a token provider with the relevant credentials.     TokenProvider credentials =         TokenProvider.CreateSharedSecretTokenProvider         (AccountDetails.Name, AccountDetails.Key);       // Create a URI for the serivce bus.     Uri serviceBusUri = ServiceBusEnvironment.CreateServiceUri         ("sb", AccountDetails.Namespace, string.Empty);       // Create the MessagingFactory     MessagingFactory factory = MessagingFactory.Create(serviceBusUri, credentials);       // Use the MessagingFactory to create a queue client     QueueClient queueClient = factory.CreateQueueClient(AccountDetails.QueueName);       // Open the input file.     FileStream fileStream = new FileStream(AccountDetails.TestFile, FileMode.Open);       // Create a BrokeredMessage for the file.     BrokeredMessage largeMessage = new BrokeredMessage(fileStream, true);       Console.WriteLine("Sending: " + AccountDetails.TestFile);     Console.WriteLine("Message body size: " + largeMessage.Size);     Console.WriteLine();         // Send the message with a LargeMessageSender     LargeMessageSender sender = new LargeMessageSender(queueClient);     sender.Send(largeMessage);       // Close the messaging facory.     factory.Close();  } The implementation of the main method of the receiving application is shown below. static void Main(string[] args) {       // Create a token provider with the relevant credentials.     TokenProvider credentials =         TokenProvider.CreateSharedSecretTokenProvider         (AccountDetails.Name, AccountDetails.Key);       // Create a URI for the serivce bus.     Uri serviceBusUri = ServiceBusEnvironment.CreateServiceUri         ("sb", AccountDetails.Namespace, string.Empty);       // Create the MessagingFactory     MessagingFactory factory = MessagingFactory.Create(serviceBusUri, credentials);       // Use the MessagingFactory to create a queue client     QueueClient queueClient = factory.CreateQueueClient(AccountDetails.QueueName);       // Create a LargeMessageReceiver and receive the message.     LargeMessageReceiver receiver = new LargeMessageReceiver(queueClient);     BrokeredMessage largeMessage = receiver.Receive();       Console.WriteLine("Received message");     Console.WriteLine("Message body size: " + largeMessage.Size);       string testFile = AccountDetails.TestFile.Replace(@"\In\", @"\Out\");     Console.WriteLine("Saving file: " + testFile);       // Save the message body as a file.     Stream largeMessageStream = largeMessage.GetBody<Stream>();     largeMessageStream.Seek(0, SeekOrigin.Begin);     FileStream fileOut = new FileStream(testFile, FileMode.Create);     largeMessageStream.CopyTo(fileOut);     fileOut.Close();       Console.WriteLine("Done!"); } In order to test the application, the sending application is executed, which will use the LargeMessageSender class to split the message and place it on the queue. The output of the sender console is shown below. The console shows that the body size of the large message was 9,929,365 bytes, and the message was sent as a sequence of 51 sub messages. When the receiving application is executed the results are shown below. The console application shows that the aggregator has received the 51 messages from the message sequence that was creating in the sending application. The messages have been aggregated to form a massage with a body of 9,929,365 bytes, which is the same as the original large message. The message body is then saved as a file. Improvements to the Implementation The splitter and aggregator patterns in this implementation were created in order to show the usage of the patterns in a demo, which they do quite well. When implementing these patterns in a real-world scenario there are a number of improvements that could be made to the design. Copying Message Header Properties When sending a large message using these classes, it would be great if the message header properties in the message that was received were copied from the message that was sent. The sending application may well add information to the message context that will be required in the receiving application. When the sub messages are created in the splitter, the header properties in the first message could be set to the values in the original large message. The aggregator could then used the values from this first sub message to set the properties in the message header of the large message during the aggregation process. Using Asynchronous Methods The current implementation uses the synchronous send and receive methods of the QueueClient class. It would be much more performant to use the asynchronous methods, however doing so may well affect the sequence in which the sub messages are enqueued, which would require the implementation of a resequencer in the aggregator to restore the correct message sequence. Handling Exceptions In order to keep the code readable no exception handling was added to the implementations. In a real-world scenario exceptions should be handled accordingly.

  Read the article

• Gmail rejects emails. Openspf.net fails the tests

  - by pablomedok

  I've got a problem with Gmail. It started after one of our trojan infected PCs sent spam for one day from our IP address. We've fixed the problem, but we got into 3 black lists. We've fixed that, too. But still every time we send an email to Gmail the message is rejected: So I've checked Google Bulk Sender's guide once again and found an error in our SPF record and fixed it. Google says everything should become fine after some time, but this doesn't happen. 3 weeks already passed but we still can't send emails to Gmail. Our MX setup is a bit complex, but not too much: We have a domain name delo-company.com, it has it's own mail @delo-company.com (this one is fine, but the problems are with sub-domain name corp.delo-company.com). Delo-company.com domain has several DNS records for the subdomain: corp A 82.209.198.147 corp MX 20 corp.delo-company.com corp.delo-company.com TXT "v=spf1 ip4:82.209.198.147 ~all" (I set ~all for testing purposes only, it was -all before that) These records are for our corporate Exchange 2003 server at 82.209.198.147. Its LAN name is s2.corp.delo-company.com so its HELO/EHLO greetings are also s2.corp.delo-company.com. To pass EHLO check we've also created some records in delo-company.com's DNS: s2.corp A 82.209.198.147 s2.corp.delo-company.com TXT "v=spf1 ip4:82.209.198.147 ~all" As I understand SPF verifications should be passed in this way: Out server s2 connects to MX of the recepient (Rcp.MX): EHLO s2.corp.delo-company.com Rcp.MX says Ok, and makes SPF check of HELO/EHLO. It does NSlookup for s2.corp.delo-company.com and gets the above DNS-records. TXT records says that s2.corp.delo-company.com should be only from IP 82.209.198.147. So it should be passed. Then our s2 server says RCPT FROM: Rcp.MX` server checks it, too. The values are the same so they should also be positive. Maybe there is also a rDNS check, but I'm not sure what is checked HELO or RCPT FROM. Our PTR record for 82.209.198.147 is: 147.198.209.82.in-addr.arpa. 86400 IN PTR s2.corp.delo-company.com. To me everything looks fine, but anyway all emails are rejected by Gmail. So, I've checked MXtoolbox.com - it says everything is fine, I passed http://www.kitterman.com/spf/validate.html Python check, I did 25port.com email test. It's fine, too: Return-Path: <[email protected]> Received: from s2.corp.delo-company.com (82.209.198.147) by verifier.port25.com id ha45na11u9cs for <[email protected]>; Fri, 2 Mar 2012 13:03:21 -0500 (envelope-from <[email protected]>) Authentication-Results: verifier.port25.com; spf=pass [email protected] Authentication-Results: verifier.port25.com; domainkeys=neutral (message not signed) [email protected] Authentication-Results: verifier.port25.com; dkim=neutral (message not signed) Authentication-Results: verifier.port25.com; sender-id=pass [email protected] Content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----_=_NextPart_001_01CCF89E.BE02A069" Subject: test Date: Fri, 2 Mar 2012 21:03:15 +0300 X-MimeOLE: Produced By Microsoft Exchange V6.5 Message-ID: <[email protected]> X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: test Thread-Index: Acz4jS34oznvbyFQR4S5rXsNQFvTdg== From: =?koi8-r?B?89XQ0tXOwMsg8MHXxcw=?= <[email protected]> To: <[email protected]> I also checked with [email protected], but it FAILs all the time, no matter which SPF records I make: <s2.corp.delo-company.com #5.7.1 smtp;550 5.7.1 <[email protected]>: Recipient address rejected: SPF Tests: Mail-From Result="softfail": Mail From="[email protected]" HELO name="s2.corp.delo-company.com" HELO Result="softfail" Remote IP="82.209.198.147"> I've filled Gmail form twice, but nothing happens. We do not send spam, only emails for our clients. 2 or 3 times we did mass emails (like New Year Greetings and sales promos) from corp.delo-company.com addresses, but they where all complying to Gmail Bulk Sender's Guide (I mean SPF, Open Relays, Precedence: Bulk and Unsubscribe tags). So, this should be not a problem. Please, help me. What am I doing wrong? UPD: I also tried Unlocktheinbox.com test and the server also fails this test. Here is the result: http://bit.ly/wYr39h . Here is one more http://bit.ly/ypWLjr I also tried to send email from that server manually via telnet and everything is fine. Here is what I type: 220 mx.google.com ESMTP g15si4811326anb.170 HELO s2.corp.delo-company.com 250 mx.google.com at your service MAIL FROM: <[email protected]> 250 2.1.0 OK g15si4811326anb.170 RCPT TO: <[email protected]> 250 2.1.5 OK g15si4811326anb.170 DATA 354 Go ahead g15si4811326anb.170 From: [email protected] To: Pavel <[email protected]> Subject: Test 28 This is telnet test . 250 2.0.0 OK 1330795021 g15si4811326anb.170 QUIT 221 2.0.0 closing connection g15si4811326anb.170 And this is what I get: Delivered-To: [email protected] Received: by 10.227.132.73 with SMTP id a9csp96864wbt; Sat, 3 Mar 2012 09:17:02 -0800 (PST) Received: by 10.101.128.12 with SMTP id f12mr4837125ann.49.1330795021572; Sat, 03 Mar 2012 09:17:01 -0800 (PST) Return-Path: <[email protected]> Received: from s2.corp.delo-company.com (s2.corp.delo-company.com. [82.209.198.147]) by mx.google.com with SMTP id g15si4811326anb.170.2012.03.03.09.15.59; Sat, 03 Mar 2012 09:17:00 -0800 (PST) Received-SPF: pass (google.com: domain of [email protected] designates 82.209.198.147 as permitted sender) client-ip=82.209.198.147; Authentication-Results: mx.google.com; spf=pass (google.com: domain of [email protected] designates 82.209.198.147 as permitted sender) [email protected] Date: Sat, 03 Mar 2012 09:17:00 -0800 (PST) Message-Id: <[email protected]> From: [email protected] To: Pavel <[email protected]> Subject: Test 28 This is telnet test

  Read the article

• MvcExtensions – Bootstrapping

  - by kazimanzurrashid

  When you create a new ASP.NET MVC application you will find that the global.asax contains the following lines: namespace MvcApplication1 { // Note: For instructions on enabling IIS6 or IIS7 classic mode, // visit http://go.microsoft.com/?LinkId=9394801 public class MvcApplication : System.Web.HttpApplication { public static void RegisterRoutes(RouteCollection routes) { routes.IgnoreRoute("{resource}.axd/{*pathInfo}"); routes.MapRoute( "Default", // Route name "{controller}/{action}/{id}", // URL with parameters new { controller = "Home", action = "Index", id = UrlParameter.Optional } // Parameter defaults ); } protected void Application_Start() { AreaRegistration.RegisterAllAreas(); RegisterRoutes(RouteTable.Routes); } } } As the application grows, there are quite a lot of plumbing code gets into the global.asax which quickly becomes a design smell. Lets take a quick look at the code of one of the open source project that I recently visited: public static void RegisterRoutes(RouteCollection routes) { routes.IgnoreRoute("{resource}.axd/{*pathInfo}"); routes.MapRoute("Default","{controller}/{action}/{id}", new { controller = "Home", action = "Index", id = "" }); } protected override void OnApplicationStarted() { Error += OnError; EndRequest += OnEndRequest; var settings = new SparkSettings() .AddNamespace("System") .AddNamespace("System.Collections.Generic") .AddNamespace("System.Web.Mvc") .AddNamespace("System.Web.Mvc.Html") .AddNamespace("MvcContrib.FluentHtml") .AddNamespace("********") .AddNamespace("********.Web") .SetPageBaseType("ApplicationViewPage") .SetAutomaticEncoding(true); #if DEBUG settings.SetDebug(true); #endif var viewFactory = new SparkViewFactory(settings); ViewEngines.Engines.Add(viewFactory); #if !DEBUG PrecompileViews(viewFactory); #endif RegisterAllControllersIn("********.Web"); log4net.Config.XmlConfigurator.Configure(); RegisterRoutes(RouteTable.Routes); Factory.Load(new Components.WebDependencies()); ModelBinders.Binders.DefaultBinder = new Binders.GenericBinderResolver(Factory.TryGet<IModelBinder>); ValidatorConfiguration.Initialize("********"); HtmlValidationExtensions.Initialize(ValidatorConfiguration.Rules); } private void OnEndRequest(object sender, System.EventArgs e) { if (((HttpApplication)sender).Context.Handler is MvcHandler) { CreateKernel().Get<ISessionSource>().Close(); } } private void OnError(object sender, System.EventArgs e) { CreateKernel().Get<ISessionSource>().Close(); } protected override IKernel CreateKernel() { return Factory.Kernel; } private static void PrecompileViews(SparkViewFactory viewFactory) { var batch = new SparkBatchDescriptor(); batch.For<HomeController>().For<ManageController>(); viewFactory.Precompile(batch); } As you can see there are quite a few of things going on in the above code, Registering the ViewEngine, Compiling the Views, Registering the Routes/Controllers/Model Binders, Settings up Logger, Validations and as you can imagine the more it becomes complex the more things will get added in the application start. One of the goal of the MVCExtensions is to reduce the above design smell. Instead of writing all the plumbing code in the application start, it contains BootstrapperTask to register individual services. Out of the box, it contains BootstrapperTask to register Controllers, Controller Factory, Action Invoker, Action Filters, Model Binders, Model Metadata/Validation Providers, ValueProvideraFactory, ViewEngines etc and it is intelligent enough to automatically detect the above types and register into the ASP.NET MVC Framework. Other than the built-in tasks you can create your own custom task which will be automatically executed when the application starts. When the BootstrapperTasks are in action you will find the global.asax pretty much clean like the following: public class MvcApplication : UnityMvcApplication { public void ErrorLog_Filtering(object sender, ExceptionFilterEventArgs e) { Check.Argument.IsNotNull(e, "e"); HttpException exception = e.Exception.GetBaseException() as HttpException; if ((exception != null) && (exception.GetHttpCode() == (int)HttpStatusCode.NotFound)) { e.Dismiss(); } } } The above code is taken from my another open source project Shrinkr, as you can see the global.asax is longer cluttered with any plumbing code. One special thing you have noticed that it is inherited from the UnityMvcApplication rather than regular HttpApplication. There are separate version of this class for each IoC Container like NinjectMvcApplication, StructureMapMvcApplication etc. Other than executing the built-in tasks, the Shrinkr also has few custom tasks which gets executed when the application starts. For example, when the application starts, we want to ensure that the default users (which is specified in the web.config) are created. The following is the custom task that is used to create those default users: public class CreateDefaultUsers : BootstrapperTask { protected override TaskContinuation ExecuteCore(IServiceLocator serviceLocator) { IUserRepository userRepository = serviceLocator.GetInstance<IUserRepository>(); IUnitOfWork unitOfWork = serviceLocator.GetInstance<IUnitOfWork>(); IEnumerable<User> users = serviceLocator.GetInstance<Settings>().DefaultUsers; bool shouldCommit = false; foreach (User user in users) { if (userRepository.GetByName(user.Name) == null) { user.AllowApiAccess(ApiSetting.InfiniteLimit); userRepository.Add(user); shouldCommit = true; } } if (shouldCommit) { unitOfWork.Commit(); } return TaskContinuation.Continue; } } There are several other Tasks in the Shrinkr that we are also using which you will find in that project. To create a custom bootstrapping task you have create a new class which either implements the IBootstrapperTask interface or inherits from the abstract BootstrapperTask class, I would recommend to start with the BootstrapperTask as it already has the required code that you have to write in case if you choose the IBootstrapperTask interface. As you can see in the above code we are overriding the ExecuteCore to create the default users, the MVCExtensions is responsible for populating the  ServiceLocator prior calling this method and in this method we are using the service locator to get the dependencies that are required to create the users (I will cover the custom dependencies registration in the next post). Once the users are created, we are returning a special enum, TaskContinuation as the return value, the TaskContinuation can have three values Continue (default), Skip and Break. The reason behind of having this enum is, in some  special cases you might want to skip the next task in the chain or break the complete chain depending upon the currently running task, in those cases you will use the other two values instead of the Continue. The last thing I want to cover in the bootstrapping task is the Order. By default all the built-in tasks as well as newly created task order is set to the DefaultOrder(a static property), in some special cases you might want to execute it before/after all the other tasks, in those cases you will assign the Order in the Task constructor. For Example, in Shrinkr, we want to run few background services when the all the tasks are executed, so we assigned the order as DefaultOrder + 1. Here is the code of that Task: public class ConfigureBackgroundServices : BootstrapperTask { private IEnumerable<IBackgroundService> backgroundServices; public ConfigureBackgroundServices() { Order = DefaultOrder + 1; } protected override TaskContinuation ExecuteCore(IServiceLocator serviceLocator) { backgroundServices = serviceLocator.GetAllInstances<IBackgroundService>().ToList(); backgroundServices.Each(service => service.Start()); return TaskContinuation.Continue; } protected override void DisposeCore() { backgroundServices.Each(service => service.Stop()); } } That’s it for today, in the next post I will cover the custom service registration, so stay tuned.

  Read the article

• Service Broker, not ETL

  - by jamiet

  I have been very quiet on this blog of late and one reason for that is I have been very busy on a client project that I would like to talk about a little here. The client that I have been working for has a website that runs on a distributed architecture utilising a messaging infrastructure for communication between different endpoints. My brief was to build a system that could consume these messages and produce analytical information in near-real-time. More specifically I basically had to deliver a data warehouse however it was the real-time aspect of the project that really intrigued me. This real-time requirement meant that using an Extract transformation, Load (ETL) tool was out of the question and so I had no choice but to write T-SQL code (i.e. stored-procedures) to process the incoming messages and load the data into the data warehouse. This concerned me though – I had no way to control the rate at which data would arrive into the system yet we were going to have end-users querying the system at the same time that those messages were arriving; the potential for contention in such a scenario was pretty high and and was something I wanted to minimise as much as possible. Moreover I did not want the processing of data inside the data warehouse to have any impact on the customer-facing website. As you have probably guessed from the title of this blog post this is where Service Broker stepped in! For those that have not heard of it Service Broker is a queuing technology that has been built into SQL Server since SQL Server 2005. It provides a number of features however the one that was of interest to me was the fact that it facilitates asynchronous data processing which, in layman’s terms, means the ability to process some data without requiring the system that supplied the data having to wait for the response. That was a crucial feature because on this project the customer-facing website (in effect an OLTP system) would be calling one of our stored procedures with each message – we did not want to cause the OLTP system to wait on us every time we processed one of those messages. This asynchronous nature also helps to alleviate the contention problem because the asynchronous processing activity is handled just like any other task in the database engine and hence can wait on another task (such as an end-user query). Service Broker it was then! The stored procedure called by the OLTP system would simply put the message onto a queue and we would use a feature called activation to pick each message off the queue in turn and process it into the warehouse. At the time of writing the system is not yet up to full capacity but so far everything seems to be working OK (touch wood) and crucially our users are seeing data in near-real-time. By near-real-time I am talking about latencies of a few minutes at most and to someone like me who is used to building systems that have overnight latencies that is a huge step forward! So then, am I advocating that you all go out and dump your ETL tools? Of course not, no! What this project has taught me though is that in certain scenarios there may be better ways to implement a data warehouse system then the traditional “load data in overnight” approach that we are all used to. Moreover I have really enjoyed getting to grips with a new technology and even if you don’t want to use Service Broker you might want to consider asynchronous messaging architectures for your BI/data warehousing solutions in the future. This has been a very high level overview of my use of Service Broker and I have deliberately left out much of the minutiae of what has been a very challenging implementation. Nonetheless I hope I have caused you to reflect upon your own approaches to BI and question whether other approaches may be more tenable. All comments and questions gratefully received! Lastly, if you have never used Service Broker before and want to kick the tyres I have provided below a very simple “Service Broker Hello World” script that will create all of the objects required to facilitate Service Broker communications and then send the message “Hello World” from one place to anther! This doesn’t represent a “proper” implementation per se because it doesn’t close down down conversation objects (which you should always do in a real-world scenario) but its enough to demonstrate the capabilities! @Jamiet ----------------------------------------------------------------------------------------------- /*This is a basic Service Broker Hello World app. Have fun! -Jamie */ USE MASTER GO CREATE DATABASE SBTest GO --Turn Service Broker on! ALTER DATABASE SBTest SET ENABLE_BROKER GO USE SBTest GO -- 1) we need to create a message type. Note that our message type is -- very simple and allowed any type of content CREATE MESSAGE TYPE HelloMessage VALIDATION = NONE GO -- 2) Once the message type has been created, we need to create a contract -- that specifies who can send what types of messages CREATE CONTRACT HelloContract (HelloMessage SENT BY INITIATOR) GO --We can query the metadata of the objects we just created SELECT * FROM   sys.service_message_types WHERE name = 'HelloMessage'; SELECT * FROM   sys.service_contracts WHERE name = 'HelloContract'; SELECT * FROM   sys.service_contract_message_usages WHERE  service_contract_id IN (SELECT service_contract_id FROM sys.service_contracts WHERE name = 'HelloContract') AND        message_type_id IN (SELECT message_type_id FROM sys.service_message_types WHERE name = 'HelloMessage'); -- 3) The communication is between two endpoints. Thus, we need two queues to -- hold messages CREATE QUEUE SenderQueue CREATE QUEUE ReceiverQueue GO --more querying metatda SELECT * FROM sys.service_queues WHERE name IN ('SenderQueue','ReceiverQueue'); --we can also select from the queues as if they were tables SELECT * FROM SenderQueue   SELECT * FROM ReceiverQueue   -- 4) Create the required services and bind them to be above created queues CREATE SERVICE Sender   ON QUEUE SenderQueue CREATE SERVICE Receiver   ON QUEUE ReceiverQueue (HelloContract) GO --more querying metadata SELECT * FROM sys.services WHERE name IN ('Receiver','Sender'); -- 5) At this point, we can begin the conversation between the two services by -- sending messages DECLARE @conversationHandle UNIQUEIDENTIFIER DECLARE @message NVARCHAR(100) BEGIN   BEGIN TRANSACTION;   BEGIN DIALOG @conversationHandle         FROM SERVICE Sender         TO SERVICE 'Receiver'         ON CONTRACT HelloContract WITH ENCRYPTION=OFF   -- Send a message on the conversation   SET @message = N'Hello, World';   SEND  ON CONVERSATION @conversationHandle         MESSAGE TYPE HelloMessage (@message)   COMMIT TRANSACTION END GO --check contents of queues SELECT * FROM SenderQueue   SELECT * FROM ReceiverQueue   GO -- Receive a message from the queue RECEIVE CONVERT(NVARCHAR(MAX), message_body) AS MESSAGE FROM ReceiverQueue GO --If no messages were received and/or you can't see anything on the queues you may wish to check the following for clues: SELECT * FROM sys.transmission_queue -- Cleanup DROP SERVICE Sender DROP SERVICE Receiver DROP QUEUE SenderQueue DROP QUEUE ReceiverQueue DROP CONTRACT HelloContract DROP MESSAGE TYPE HelloMessage GO USE MASTER GO DROP DATABASE SBTest GO

  Read the article

• C# UDP decoding datagrams fails randomly

  - by Tom Frey

  Hi, I'm experiencing an issue in a multi threaded application and have been debugging it for the last 3 days but for the life of it can not figure it out. I'm writing this, hoping that I either have a DUH moment when typing this or somebody sees something obvious in the code snippets I provide. Here's what's going on: I've been working on a new UDP networking library and have a data producer that multicasts UDP datagrams to several receiver applications. The sender sends on two different sockets that are bound to separate UDP multicast addresses and separate ports. The receiver application also creates two sockets and binds each one to one of the sender's multicast address/port. When the receiver receives the datagram, it copies it from the the buffer in a MemoryStream which is then put onto a thread safe queue, where another thread reads from it and decodes the data out of the MemoryStream. Both sockets have their own queues. What happens now is really weird, it happens randomly, non-reproducible and when I run multiple receiver applications, it only happens randomly on one of them every now and then. Basically, the thread that reads the MemoryStream out of the queue, reads it via a BinaryReader like ReadInt32(), etc. and thereby decodes the data. Every now and then however when it reads the data, the data it reads from it is incorrect, e.g. a negative integer number which the sender never would encode. However, as mentioned before, the decoding only fails in one of the receiver applications, in the other ones the datagram decodes fine. Now you might be saying, well, probably the UDP datagram has a byte corruption or something but I've logged every single datagram that's coming in and compared them on all receivers and the datagrams every application receives are absolutely identical. Now it gets even weirder, when I dump the datagram that failed to decode to disk and write a unit test that reads it and runs it through the decoder, it decodes just fine. Also when I wrap a try/catch around the decoder, reset the MemoryStream position in the catch and run it through the decoder again, it decodes just fine. To make it even weirder, this also only happens when I bind both sockets to read data from the sender, if I only bind one, it doesn't happen or at least I wasn't able to reproduce it. Here are is some corresponding code to what's going on: This is the receive callback for the socket: private void ReceiveCompleted(object sender, SocketAsyncEventArgs args) { if (args.SocketError != SocketError.Success) { InternalShutdown(args.SocketError); return; } if (args.BytesTransferred > SequencedUnitHeader.UNIT_HEADER_SIZE) { DataChunk chunk = new DataChunk(args.BytesTransferred); Buffer.BlockCopy(args.Buffer, 0, chunk.Buffer, 0, args.BytesTransferred); chunk.MemoryStream = new MemoryStream(chunk.Buffer); chunk.BinaryReader = new BinaryReader(chunk.MemoryStream); chunk.SequencedUnitHeader.SequenceID = chunk.BinaryReader.ReadUInt32(); chunk.SequencedUnitHeader.Count = chunk.BinaryReader.ReadByte(); if (prevSequenceID + 1 != chunk.SequencedUnitHeader.SequenceID) { log.Error("UdpDatagramGap\tName:{0}\tExpected:{1}\tReceived:{2}", unitName, prevSequenceID + 1, chunk.SequencedUnitHeader.SequenceID); } else if (chunk.SequencedUnitHeader.SequenceID < prevSequenceID) { log.Error("UdpOutOfSequence\tName:{0}\tExpected:{1}\tReceived:{2}", unitName, prevSequenceID + 1, chunk.SequencedUnitHeader.SequenceID); } prevSequenceID = chunk.SequencedUnitHeader.SequenceID; messagePump.Produce(chunk); } else UdpStatistics.FramesRxDiscarded++; Socket.InvokeAsyncMethod(Socket.ReceiveAsync, ReceiveCompleted, asyncReceiveArgs); } Here's some stub code that decodes the data: public static void OnDataChunk(DataChunk dataChunk) { try { for (int i = 0; i < dataChunk.SequencedUnitHeader.Count; i++) { int val = dataChunk.BinaryReader.ReadInt32(); if(val < 0) throw new Exception("EncodingException"); // do something with that value } } catch (Exception ex) { writer.WriteLine("ID:" + dataChunk.SequencedUnitHeader.SequenceID + " Count:" + dataChunk.SequencedUnitHeader.Count + " " + BitConverter.ToString(dataChunk.Buffer, 0, dataChunk.Size)); writer.Flush(); log.ErrorException("OnDataChunk", ex); log.Info("RETRY FRAME:{0} Data:{1}", dataChunk.SequencedUnitHeader.SequenceID, BitConverter.ToString(dataChunk.Buffer, 0, dataChunk.Size)); dataChunk.MemoryStream.Position = 0; dataChunk.SequencedUnitHeader.SequenceID = dataChunk.BinaryReader.ReadUInt32(); dataChunk.SequencedUnitHeader.Count = dataChunk.BinaryReader.ReadByte(); OnDataChunk(dataChunk); } } You see in the catch{} part I simply reset the MemoryStream.Position to 0 and call the same method again and it works just fine that next time? I'm really out of ideas at this point and unfortunately had no DUH moment writing this. Anybody have any kind of idea what might be going on or what else I could do to troubleshoot this? Thanks, Tom

  Read the article

• Refresh page isnt working in asp.net using treeview

  - by Greg

  Hi, I am trying to refresh an asp.net page using this command: <meta http-equiv="Refresh" content="10"/> On that page I have 2 treeviews. The refresh works ok when I just open the page, but when I click on one of the treeviews and expand it, the refresh stopps working and the page isnt being refreshed. Any ideas why this can happen? Is there any connection to the treeview being expanded? Here is the full code of the page: public partial class Results : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { } // Function that moves reviewed yellow card to reviewed tree protected void ycActiveTree_SelectedNodeChanged(object sender, EventArgs e) { ycActiveTree.SelectedNode.Text = "Move To Active"; ycReviewedTree.PopulateNodesFromClient = false; ycReviewedTree.Nodes[ycReviewedTree.Nodes.Count - 1].ChildNodes.Add(ycActiveTree.SelectedNode.Parent); Application["reviewedTree"] = new ArrayList(); int count = ((ArrayList)Application["activeTree"]).Count; // Move all the nodes from activeTree application to reviewedTree application for (int i = 0; Application["activeTree"] != null && i < count; i++) { ((ArrayList)Application["reviewedTree"]).Add(((ArrayList)Application["activeTree"])[i]); ((ArrayList)Application["activeTree"]).RemoveAt(0); } } protected void ycActiveTree_TreeNodePopulate(object sender, TreeNodeEventArgs e) { if (Application["idList"] != null && e.Node.Depth == 0) { string[] words = ((String)Application["idList"]).Split(' '); // Yellow Card details TreeNode child = new TreeNode(""); // Go over all the yellow card details and populate the treeview for (int i = 1; i < words.Length; i++) { child.SelectAction = TreeNodeSelectAction.None; // Same yellow card if (words[i] != "*") { // End of details and start of point ip's if (words[i] == "$") { // Add the yellow card node TreeNode yellowCardNode = new TreeNode(child.Text); yellowCardNode.SelectAction = TreeNodeSelectAction.Expand; e.Node.ChildNodes.Add(yellowCardNode); child.Text = ""; } // yellow card details else { child.Text = child.Text + words[i] + " "; } } // End of yellow card else { child.PopulateOnDemand = false; child.SelectAction = TreeNodeSelectAction.None; // Populate the yellow card node e.Node.ChildNodes[e.Node.ChildNodes.Count - 1].ChildNodes.Add(child); TreeNode moveChild = new TreeNode("Move To Reviewed"); moveChild.PopulateOnDemand = false; moveChild.SelectAction = TreeNodeSelectAction.Select; e.Node.ChildNodes[e.Node.ChildNodes.Count - 1].ChildNodes.Add(moveChild); child = new TreeNode(""); Application["activeTree"] = new ArrayList(); ((ArrayList)Application["activeTree"]).Add(e.Node.ChildNodes[e.Node.ChildNodes.Count - 1]); } } } // If there arent new yellow cards else if (Application["activeTree"] != null) { // Populate the active tree for (int i = 0; i < ((ArrayList)Application["activeTree"]).Count; i++) { e.Node.ChildNodes.Add((TreeNode)((ArrayList)Application["activeTree"])[i]); } } // If there were new yellow cards and nodes that moved from reviewed tree to active tree if (Application["idList"] != null && Application["activeTree"] != null && e.Node.ChildNodes.Count != ((ArrayList)Application["activeTree"]).Count) { for (int i = e.Node.ChildNodes.Count; i < ((ArrayList)Application["activeTree"]).Count; i++) { e.Node.ChildNodes.Add((TreeNode)((ArrayList)Application["activeTree"])[i]); } } // Nullify the yellow card id's Application["idList"] = null; } protected void ycReviewedTree_SelectedNodeChanged(object sender, EventArgs e) { ycActiveTree.PopulateNodesFromClient = false; ycReviewedTree.SelectedNode.Text = "Move To Reviewed"; ycActiveTree.Nodes[ycActiveTree.Nodes.Count - 1].ChildNodes.Add(ycReviewedTree.SelectedNode.Parent); int count = ((ArrayList)Application["reviewedTree"]).Count; // Move all the nodes from reviewedTree application to activeTree application for (int i = 0; Application["reviewedTree"] != null && i < count; i++) { ((ArrayList)Application["activeTree"]).Add(((ArrayList)Application["reviewedTree"])[i]); ((ArrayList)Application["reviewedTree"]).RemoveAt(0); } } protected void ycReviewedTree_TreeNodePopulate(object sender, TreeNodeEventArgs e) { if (Application["reviewedTree"] != null) { // Populate the reviewed tree for (int i = 0; i < ((ArrayList)Application["reviewedTree"]).Count; i++) { e.Node.ChildNodes.Add((TreeNode)((ArrayList)Application["reviewedTree"])[i]); } } } } Thanks, Greg

  Read the article

• How can I keep a graphics object centered (like a circle) when zooming in or out on it?

  - by sonny5

  using System; using System.Drawing; using System.Collections; using System.ComponentModel; using System.Windows.Forms; using System.Data; using System.Drawing.Drawing2D; using System.Drawing.Imaging; namespace testgrfx { public class Form1 : System.Windows.Forms.Form { float m_Scalef; float m_Scalefout; Rectangle m_r1; private System.Windows.Forms.Button button2; private System.Windows.Forms.Button button3; private System.ComponentModel.Container components = null; private void InitializeComponent() { m_Scalef = 1.0f; // for zooming purposes Console.WriteLine("opening m_Scalef= {0}",m_Scalef); m_Scalefout = 1.0f; Console.WriteLine("opening m_Scalefout= {0}",m_Scalefout); m_r1 = new Rectangle(50,50,100,100); this.AutoScrollMinSize = new Size(600,700); this.components = new System.ComponentModel.Container(); this.button2 = new System.Windows.Forms.Button(); this.button2.BackColor = System.Drawing.Color.LightGray; this.button2.Location = new System.Drawing.Point(120, 30); this.button2.Name = "button2"; this.button2.Size = new System.Drawing.Size(72, 24); this.button2.TabIndex = 1; this.button2.Text = "Zoom In"; this.button2.Click += new System.EventHandler(this.mnuZoomin_Click); this.Controls.Add(button2); this.button3 = new System.Windows.Forms.Button(); this.button3.BackColor = System.Drawing.Color.LightGray; this.button3.Location = new System.Drawing.Point(200, 30); this.button3.Name = "button3"; this.button3.Size = new System.Drawing.Size(72, 24); this.button3.TabIndex = 2; this.button3.Text = "Zoom Out"; this.button3.Click += new System.EventHandler(this.mnuZoomout_Click); this.Controls.Add(button3); //InitMyForm(); } public Form1() { InitializeComponent(); Text = " DrawLine"; BackColor = SystemColors.Window; // Gotta load these kind at start-up ... not with button assignments this.Paint+=new PaintEventHandler(this.Form1_Paint); } static void Main() { Application.Run(new Form1()); } /// Clean up any resources being used. protected override void Dispose( bool disposing ) { if( disposing ) { if (components != null) { components.Dispose(); } } base.Dispose( disposing ); } // autoscroll2.cs does work private void Form1_Paint(object sender, System.Windows.Forms.PaintEventArgs e) { Graphics dc = e.Graphics; dc.PageUnit = GraphicsUnit.Pixel; dc.PageScale = m_Scalef; Console.WriteLine("opening dc.PageScale= {0}",dc.PageScale); dc.TranslateTransform(this.AutoScrollPosition.X/m_Scalef, this.AutoScrollPosition.Y/m_Scalef); Pen pn = new Pen(Color.Blue,2); dc.DrawEllipse(pn,m_r1); Console.WriteLine("form_paint_dc.PageUnit= {0}",dc.PageUnit); Console.WriteLine("form_paint_dc.PageScale= {0}",dc.PageScale); //Console.Out.NewLine = "\r\n\r\n"; // makes all double spaces } private void mnuZoomin_Click(object sender, System.EventArgs e) { m_Scalef = m_Scalef * 2.0f; Console.WriteLine("in mnuZoomin_Click m_Scalef= {0}",m_Scalef); Invalidate(); // to trigger Paint of entire client area } // try: System.Drawing.Rectangle resolution = Screen.GetWorkingArea(someForm); private void Form1_MouseDown(object sender, System.Windows.Forms.MouseEventArgs e) { // Uses the mouse wheel to scroll Graphics dc = CreateGraphics(); dc.TranslateTransform(this.AutoScrollPosition.X/m_Scalef, this.AutoScrollPosition.Y/m_Scalef); Console.WriteLine("opening Form1_MouseDown dc.PageScale= {0}", dc.PageScale); Console.WriteLine("Y wheel= {0}", this.AutoScrollPosition.Y/m_Scalef); dc.PageUnit = GraphicsUnit.Pixel; dc.PageScale = m_Scalef; Console.WriteLine("frm1_moudwn_dc.PageScale= {0}",dc.PageScale); Point [] mousep = new Point[1]; Console.WriteLine("mousep= {0}", mousep); // make sure to adjust mouse pos.for scroll position Size scrollOffset = new Size(this.AutoScrollPosition); mousep[0] = new Point(e.X-scrollOffset.Width, e.Y-scrollOffset.Height); dc.TransformPoints(CoordinateSpace.Page, CoordinateSpace.Device,mousep); Pen pen = new Pen(Color.Green,1); dc.DrawRectangle(pen,m_r1); Console.WriteLine("m_r1= {0}", m_r1); Console.WriteLine("mousep[0].X= {0}", mousep[0].X); Console.WriteLine("mousep[0].Y= {0}", mousep[0].Y); if (m_r1.Contains(new Rectangle(mousep[0].X, mousep[0].Y,1,1))) MessageBox.Show("click inside rectangle"); } private void Form1_Load(object sender, System.EventArgs e) { } private void mnuZoomout_Click(object sender, System.EventArgs e) { Console.WriteLine("first line--mnuZoomout_Click m_Scalef={0}",m_Scalef); if(m_Scalef > 9 ) { m_Scalef = m_Scalef / 2.0f; Console.WriteLine("in >9 mnuZoomout_Click m_Scalef= {0}",m_Scalef); Console.WriteLine("in >9 mnuZoomout_Click__m_Scalefout= {0}",m_Scalefout); } else { Console.WriteLine("<= 9_Zoom-out B-4 redefining={0}",m_Scalef); m_Scalef = m_Scalef * 0.5f; // make it same as previous Zoom In Console.WriteLine("<= 9_Zoom-out after m_Scalef= {0}",m_Scalef); } Invalidate(); } } // public class Form1 }

  Read the article

• Pixel plot method errors out without error message.

  - by sonny5

  // The following method blows up (big red x on screen) without generating error info. Any // ideas why? // MyPlot.PlotPixel(x, y, Color.BlueViolet, Grf); // runs if commented out // My goal is to draw a pixel on a form. Is there a way to increase the pixel size also? using System; using System.Drawing; using System.Drawing.Drawing2D; using System.Collections; using System.ComponentModel; using System.Windows.Forms; using System.Data; public class Plot : System.Windows.Forms.Form { private Size _ClientArea; //keeps the pixels info private double _Xspan; private double _Yspan; public Plot() { InitializeComponent(); } public Size ClientArea { set { _ClientArea = value; } } private void InitializeComponent() { this.AutoScaleBaseSize = new System.Drawing.Size(5, 13); this.ClientSize = new System.Drawing.Size(400, 300); this.Text="World Plot (world_plot.cs)"; this.Resize += new System.EventHandler(this.Form1_Resize); this.Paint += new System.Windows.Forms.PaintEventHandler(this.doLine); this.Paint += new System.Windows.Forms.PaintEventHandler(this.TransformPoints); // new this.Paint += new System.Windows.Forms.PaintEventHandler(this.DrawRectangleFloat); this.Paint += new System.Windows.Forms.PaintEventHandler(this.DrawWindow_Paint); } private void DrawWindow_Paint(object sender, PaintEventArgs e) { Graphics Grf = e.Graphics; pixPlot(Grf); } static void Main() { Application.Run(new Plot()); } private void doLine(object sender, System.Windows.Forms.PaintEventArgs e) { // no transforms done yet!!! Graphics g = e.Graphics; g.FillRectangle(Brushes.White, this.ClientRectangle); Pen p = new Pen(Color.Black); g.DrawLine(p, 0, 0, 100, 100); // draw DOWN in y, which is positive since no matrix called p.Dispose(); } public void PlotPixel(double X, double Y, Color C, Graphics G) { Bitmap bm = new Bitmap(1, 1); bm.SetPixel(0, 0, C); G.DrawImageUnscaled(bm, TX(X), TY(Y)); } private int TX(double X) //transform real coordinates to pixels for the X-axis { double w; w = _ClientArea.Width / _Xspan * X + _ClientArea.Width / 2; return Convert.ToInt32(w); } private int TY(double Y) //transform real coordinates to pixels for the Y-axis { double w; w = _ClientArea.Height / _Yspan * Y + _ClientArea.Height / 2; return Convert.ToInt32(w); } private void pixPlot(Graphics Grf) { Plot MyPlot = new Plot(); double x = 12.0; double y = 10.0; MyPlot.ClientArea = this.ClientSize; Console.WriteLine("x = {0}", x); Console.WriteLine("y = {0}", y); //MyPlot.PlotPixel(x, y, Color.BlueViolet, Grf); // blows up } private void DrawRectangleFloat(object sender, PaintEventArgs e) { // Create pen. Pen penBlu = new Pen(Color.Blue, 2); // Create location and size of rectangle. float x = 0.0F; float y = 0.0F; float width = 200.0F; float height = 200.0F; // translate DOWN by 200 pixels // Draw rectangle to screen. e.Graphics.DrawRectangle(penBlu, x, y, width, height); } private void TransformPoints(object sender, System.Windows.Forms.PaintEventArgs e) { // after transforms Graphics g = this.CreateGraphics(); Pen penGrn = new Pen(Color.Green, 3); Matrix myMatrix2 = new Matrix(1, 0, 0, -1, 0, 0); // flip Y axis with -1 g.Transform = myMatrix2; g.TranslateTransform(0, 200, MatrixOrder.Append); // translate DOWN the same distance as the rectangle... // ...so this will put it at lower left corner g.DrawLine(penGrn, 0, 0, 100, 90); // notice that y 90 is going UP } private void Form1_Resize(object sender, System.EventArgs e) { Invalidate(); } }

  Read the article

• Data table columns become out of order after changing data source.

  - by Scott Chamberlain

  This is kind of a oddball problem so I will try to describe the best that I can. I have a DataGridView that shows a list of contracts and various pieces of information about them. There are three view modes: Contract Approval, Pre-Production, and Production. Each mode has it's own set of columns that need to be displayed. What I have been doing is I have three radio buttons one for each contract style. all of them fire their check changed on this function private void rbContracts_CheckedChanged(object sender, EventArgs e) { dgvContracts.Columns.Clear(); if (((RadioButton)sender).Checked == true) { if (sender == rbPreProduction) { dgvContracts.Columns.AddRange(searchSettings.GetPreProductionColumns()); this.contractsBindingSource.DataMember = "Preproduction"; this.preproductionTableAdapter.Fill(this.searchDialogDataSet.Preproduction); } else if (sender == rbProduction) { dgvContracts.Columns.AddRange(searchSettings.GetProductionColumns()); this.contractsBindingSource.DataMember = "Production"; this.productionTableAdapter.Fill(this.searchDialogDataSet.Production); } else if (sender == rbContracts) { dgvContracts.Columns.AddRange(searchSettings.GetContractsColumns()); this.contractsBindingSource.DataMember = "Contracts"; this.contractsTableAdapter.Fill(this.searchDialogDataSet.Contracts); } } } Here is the GetxxxColumns function public DataGridViewColumn[] GetPreProductionColumns() { this.dgvTxtPreAccount.Visible = DgvTxtPreAccountVisable; this.dgvTxtPreImpromedAccNum.Visible = DgvTxtPreImpromedAccNumVisable; this.dgvTxtPreCreateDate.Visible = DgvTxtPreCreateDateVisable; this.dgvTxtPreCurrentSoftware.Visible = DgvTxtPreCurrentSoftwareVisable; this.dgvTxtPreConversionRequired.Visible = DgvTxtPreConversionRequiredVisable; this.dgvTxtPreConversionLevel.Visible = DgvTxtPreConversionLevelVisable; this.dgvTxtPreProgrammer.Visible = DgvTxtPreProgrammerVisable; this.dgvCbxPreEdge.Visible = DgvCbxPreEdgeVisable; this.dgvCbxPreEducationRequired.Visible = DgvCbxPreEducationRequiredVisable; this.dgvTxtPreTargetMonth.Visible = DgvTxtPreTargetMonthVisable; this.dgvCbxPreEdgeDatesDate.Visible = DgvCbxPreEdgeDatesDateVisable; this.dgvTxtPreStartDate.Visible = DgvTxtPreStartDateVisable; this.dgvTxtPreUserName.Visible = DgvTxtPreUserNameVisable; this.dgvCbxPreProductionId.Visible = DgvCbxPreProductionIdVisable; return new System.Windows.Forms.DataGridViewColumn[] { this.dgvTxtPreAccount, this.dgvTxtPreImpromedAccNum, this.dgvTxtPreCreateDate, this.dgvTxtPreCurrentSoftware, this.dgvTxtPreConversionRequired, this.dgvTxtPreConversionLevel, this.dgvTxtPreProgrammer, this.dgvCbxPreEdge, this.dgvCbxPreEducationRequired, this.dgvTxtPreTargetMonth, this.dgvCbxPreEdgeDatesDate, this.dgvTxtPreStartDate, this.dgvTxtPreUserName, this.dgvCbxPreProductionId, this.dgvTxtCmnHold, this.dgvTxtCmnConcern, this.dgvTxtCmnAccuracyStatus, this.dgvTxtCmnEconomicStatus, this.dgvTxtCmnSoftwareStatus, this.dgvTxtCmnServiceStatus, this.dgvTxtCmnHardwareStatus, this.dgvTxtCmnAncillaryStatus, this.dgvTxtCmnFlowStatus, this.dgvTxtCmnImpromedAccountNum, this.dgvTxtCmnOpportunityId}; } public DataGridViewColumn[] GetProductionColumns() { this.dgvcTxtProAccount.Visible = DgvTxtProAccountVisable; this.dgvTxtProImpromedAccNum.Visible = DgvTxtProImpromedAccNumVisable; this.dgvTxtProCreateDate.Visible = DgvTxtProCreateDateVisable; this.dgvTxtProConvRequired.Visible = DgvTxtProConvRequiredVisable; this.dgvTxtProEdgeRequired.Visible = DgvTxtProEdgeRequiredVisable; this.dgvTxtProStartDate.Visible = DgvTxtProStartDateVisable; this.dgvTxtProHardwareRequired.Visible = DgvTxtProHardwareReqiredVisable; this.dgvTxtProStandardDate.Visible = DgvTxtProStandardDateVisable; this.dgvTxtProSystemScheduleDate.Visible = DgvTxtProSystemScheduleDateVisable; this.dgvTxtProHwSystemCompleteDate.Visible = DgvTxtProHwSystemCompleteDateVisable; this.dgvTxtProHardwareTechnician.Visible = DgvTxtProHardwareTechnicianVisable; return new System.Windows.Forms.DataGridViewColumn[] { this.dgvcTxtProAccount, this.dgvTxtProImpromedAccNum, this.dgvTxtProCreateDate, this.dgvTxtProConvRequired, this.dgvTxtProEdgeRequired, this.dgvTxtProStartDate, this.dgvTxtProHardwareRequired, this.dgvTxtProStandardDate, this.dgvTxtProSystemScheduleDate, this.dgvTxtProHwSystemCompleteDate, this.dgvTxtProHardwareTechnician, this.dgvTxtCmnHold, this.dgvTxtCmnConcern, this.dgvTxtCmnAccuracyStatus, this.dgvTxtCmnEconomicStatus, this.dgvTxtCmnSoftwareStatus, this.dgvTxtCmnServiceStatus, this.dgvTxtCmnHardwareStatus, this.dgvTxtCmnAncillaryStatus, this.dgvTxtCmnFlowStatus, this.dgvTxtCmnImpromedAccountNum, this.dgvTxtCmnOpportunityId}; } public DataGridViewColumn[] GetContractsColumns() { this.dgvTxtConAccount.Visible = this.DgvTxtConAccountVisable; this.dgvTxtConAccuracyStatus.Visible = this.DgvTxtConAccuracyStatusVisable; this.dgvTxtConCreateDate.Visible = this.DgvTxtConCreateDateVisable; this.dgvTxtConEconomicStatus.Visible = this.DgvTxtConEconomicStatusVisable; this.dgvTxtConHardwareStatus.Visible = this.DgvTxtConHardwareStatusVisable; this.dgvTxtConImpromedAccNum.Visible = this.DgvTxtConImpromedAccNumVisable; this.dgvTxtConServiceStatus.Visible = this.DgvTxtConServiceStatusVisable; this.dgvTxtConSoftwareStatus.Visible = this.DgvTxtConSoftwareStatusVisable; this.dgvCbxConPreProductionId.Visible = this.DgvCbxConPreProductionIdVisable; this.dgvCbxConProductionId.Visible = this.DgvCbxConProductionVisable; return new System.Windows.Forms.DataGridViewColumn[] { this.dgvTxtConAccount, this.dgvTxtConImpromedAccNum, this.dgvTxtConCreateDate, this.dgvTxtConAccuracyStatus, this.dgvTxtConEconomicStatus, this.dgvTxtConSoftwareStatus, this.dgvTxtConServiceStatus, this.dgvTxtConHardwareStatus, this.dgvCbxConPreProductionId, this.dgvCbxConProductionId, this.dgvTxtCmnHold, this.dgvTxtCmnConcern, this.dgvTxtCmnAccuracyStatus, this.dgvTxtCmnEconomicStatus, this.dgvTxtCmnSoftwareStatus, this.dgvTxtCmnServiceStatus, this.dgvTxtCmnHardwareStatus, this.dgvTxtCmnAncillaryStatus, this.dgvTxtCmnFlowStatus, this.dgvTxtCmnImpromedAccountNum, this.dgvTxtCmnOpportunityId}; } The issue is when I check a button the first time, everything shows up ok. I choose another view, everything is ok. But when I click on the first view the columns are out of order (it is like they are in reverse order but it is not exactly the same). this happens only to the first page you click on, the other two are fine. You can click off and click back on as many times as you want after those initial steps, The first list you selected at the start will be out of order the other two will be correct. Any ideas on what could be causing this?

  Read the article

• Part 3 of 4 : Tips/Tricks for Silverlight Developers.

  - by mbcrump

  Part 1 | Part 2 | Part 3 | Part 4 I wanted to create a series of blog post that gets right to the point and is aimed specifically at Silverlight Developers. The most important things I want this series to answer is : What is it?  Why do I care? How do I do it? I hope that you enjoy this series. Let’s get started: Tip/Trick #11) What is it? Underline Text in a TextBlock. Why do I care? I’ve seen people do some crazy things to get underlined text in a Silverlight Application. In case you didn’t know there is a property for that. How do I do it: On a TextBlock you have a property called TextDecorations. You can easily set this property in XAML or CodeBehind with the following snippet: <UserControl x:Class="SilverlightApplication19.MainPage" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" mc:Ignorable="d" d:DesignHeight="300" d:DesignWidth="400"> <Grid x:Name="LayoutRoot" Background="White"> <TextBlock Name="txtTB" Text="MichaelCrump.NET" TextDecorations="Underline" /> </Grid> </UserControl> or you can do it in CodeBehind… txtTB.TextDecorations = TextDecorations.Underline;   Tip/Trick #12) What is it? Get the browser information from a Silverlight Application. Why do I care? This will allow you to program around certain browser conditions that otherwise may not be aware of. How do I do it: It is very easy to extract Browser Information out a Silverlight Application by using the BrowserInformation class. You can copy/paste this code snippet to have access to all of them. string strBrowserName = HtmlPage.BrowserInformation.Name; string strBrowserMinorVersion = HtmlPage.BrowserInformation.BrowserVersion.Minor.ToString(); string strIsCookiesEnabled = HtmlPage.BrowserInformation.CookiesEnabled.ToString(); string strPlatform = HtmlPage.BrowserInformation.Platform; string strProductName = HtmlPage.BrowserInformation.ProductName; string strProductVersion = HtmlPage.BrowserInformation.ProductVersion; string strUserAgent = HtmlPage.BrowserInformation.UserAgent; string strBrowserVersion = HtmlPage.BrowserInformation.BrowserVersion.ToString(); string strBrowserMajorVersion = HtmlPage.BrowserInformation.BrowserVersion.Major.ToString(); Tip/Trick #13) What is it? Always check the minRuntimeVersion after creating a new Silverlight Application. Why do I care? Whenever you create a new Silverlight Application and host it inside of an ASP.net website you will notice Visual Studio generates some code for you as shown below. The minRuntimeVersion value is set by the SDK installed on your system. Be careful, if you are playing with beta’s like “Lightswitch” because you will have a higher version of the SDK installed. So when you create a new Silverlight 4 project and deploy it your customers they will get a prompt telling them they need to upgrade Silverlight. They also will not be able to upgrade to your version because its not released to the public yet. How do I do it: Open up the .aspx or .html file Visual Studio generated and look for the line below. Make sure it matches whatever version you are actually targeting. Tip/Trick #14) What is it? The VisualTreeHelper class provides useful methods for involving nodes in a visual tree. Why do I care? It’s nice to have the ability to “walk” a visual tree or to get the rendered elements of a ListBox. I have it very useful for debugging my Silverlight application. How do I do it: Many examples exist on the web, but say that you have a huge Silverlight application and want to find the parent object of a control.  In the code snippet below, we would get 3 MessageBoxes with (StackPanel first, Grid second and UserControl Third). This is a tiny application, but imagine how helpful this would be on a large project. <UserControl x:Class="SilverlightApplication18.MainPage" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" mc:Ignorable="d" d:DesignHeight="300" d:DesignWidth="400"> <Grid x:Name="LayoutRoot" Background="White"> <StackPanel> <Button Content="Button" Height="23" Name="button1" VerticalAlignment="Top" Width="75" Click="button1_Click" /> </StackPanel> </Grid> </UserControl> private void button1_Click(object sender, RoutedEventArgs e) { DependencyObject obj = button1; while ((obj = VisualTreeHelper.GetParent(obj)) != null) { MessageBox.Show(obj.GetType().ToString()); } } Tip/Trick #15) What is it? Add ChildWindows to your Silverlight Application. Why do I care? ChildWindows are a great way to direct a user attention to a particular part of your application. This could be used when saving or entering data. How do I do it: Right click your Silverlight Application and click Add then New Item. Select Silverlight Child Window as shown below. Add an event and call the ChildWindow with the following snippet below: private void button1_Click(object sender, RoutedEventArgs e) { ChildWindow1 cw = new ChildWindow1(); cw.Show(); } Your main application can still process information but this screen forces the user to select an action before proceeding. The code behind of the ChildWindow will look like the following: namespace SilverlightApplication18 { public partial class ChildWindow1 : ChildWindow { public ChildWindow1() { InitializeComponent(); } private void OKButton_Click(object sender, RoutedEventArgs e) { this.DialogResult = true; //TODO: Add logic to save what the user entered. } private void CancelButton_Click(object sender, RoutedEventArgs e) { this.DialogResult = false; } } } Thanks for reading and please come back for Part 4.  Subscribe to my feed CodeProject

  Read the article

• asp.net how to add TemplateField programmatically for about 10 dropdownlist...

  - by dotnet-practitioner

  This is my third time asking this question. I am not getting good answers regarding this. I wish I could get some help but I will keep asking this question because its a good question and SO experts should not ignore this... So I have about 10 dropdownlist controls that I add manually in the DetailsView control manually like follows. I should be able to add this programmatically. Please help and do not ignore... <asp:DetailsView ID="dvProfile" runat="server" AutoGenerateRows="False" DataKeyNames="memberid" DataSourceID="SqlDataSource1" OnPreRender = "_onprerender" Height="50px" onm="" Width="125px"> <Fields> <asp:TemplateField HeaderText="Your Gender"> <EditItemTemplate> <asp:DropDownList ID="ddlGender" runat="server" DataSourceid="ddlDAGender" DataTextField="Gender" DataValueField="GenderID" SelectedValue='<%#Bind("GenderID") %>' > </asp:DropDownList> </EditItemTemplate> <ItemTemplate > <asp:Label Runat="server" Text='<%# Bind("Gender") %>' ID="lblGender"></asp:Label> </ItemTemplate> so on and so forth... <asp:CommandField ShowEditButton="True" ShowInsertButton="True" /> </Fields> </asp:DetailsView> ======================================================= Added on 5/3/09 This is what I have so far and I still can not add the drop down list programmatically. private void PopulateItemTemplate(string luControl) { SqlDataSource ds = new SqlDataSource(); ds = (SqlDataSource)FindControl("ddlDAGender"); DataView dvw = new DataView(); DataSourceSelectArguments args = new DataSourceSelectArguments(); dvw = (DataView)ds.Select(args); DataTable dt = dvw.ToTable(); DetailsView dv = (DetailsView)LoginView2.FindControl("dvProfile"); TemplateField tf = new TemplateField(); tf.HeaderText = "Your Gender"; tf.ItemTemplate = new ProfileItemTemplate("Gender", ListItemType.Item); tf.EditItemTemplate = new ProfileItemTemplate("Gender", ListItemType.EditItem); dv.Fields.Add(tf); } public class ProfileItemTemplate : ITemplate { private string ctlName; ListItemType _lit; private string _strDDLName; private string _strDVField; private string _strDTField; private string _strSelectedID; private DataTable _dt; public ProfileItemTemplate(string strDDLName, string strDVField, string strDTField, DataTable dt ) { _dt = dt; _strDDLName = strDDLName; _strDVField = strDVField; _strDTField = strDTField; } public ProfileItemTemplate(string strDDLName, string strDVField, string strDTField, string strSelectedID, DataTable dt ) { _dt = dt; _strDDLName = strDDLName; _strDVField = strDVField; _strDTField = strDTField; _strSelectedID = strSelectedID; } public ProfileItemTemplate(string ControlName, ListItemType lit) { ctlName = ControlName; _lit = lit; } public void InstantiateIn(Control container) { switch(_lit) { case ListItemType.Item : Label lbl = new Label(); lbl.DataBinding += new EventHandler(this.ddl_DataBinding_item); container.Controls.Add(lbl); break; case ListItemType.EditItem : DropDownList ddl = new DropDownList(); ddl.DataBinding += new EventHandler(this.lbl_DataBinding); container.Controls.Add(ddl); break; } } private void ddl_DataBinding_item(object sender, EventArgs e) { DropDownList ddl = (DropDownList)sender; ddl.ID = _strDDLName; ddl.DataSource = _dt; ddl.DataValueField = _strDVField; ddl.DataTextField = _strDVField; } private void lbl_DataBinding(object sender, EventArgs e) { Label lbl = (Label)sender; lbl.ID = "lblGender"; DropDownList ddl = (DropDownList)sender; ddl.ID = _strDDLName; ddl.DataSource = _dt; ddl.DataValueField = _strDVField; ddl.DataTextField = _strDTField; for (int i = 0; i < _dt.Rows.Count; i++) { if (_strSelectedID == _dt.Rows[i][_strDVField].ToString()) { ddl.SelectedIndex = i; } } lbl.Text = ddl.SelectedValue; } } Please help me....

  Read the article

• Preventing ListBox scrolling to top when updated

  - by WDZ

  I'm trying to build a simple music player with a ListBox playlist. When adding audio files to the playlist, it first fills the ListBox with the filenames and then (on a separate thread) extracts the ID3 data and overwrites the filenames with the correct Artist - Title information (much like Winamp). But while the ListBox is being updated, it's unscrollable, as it always jumps to the top on every item overwrite. Any way to prevent this? EDIT: The code: public Form1() { //Some initialization code omitted here BindingList<TAG_INFO> trackList = new BindingList<TAG_INFO>(); // The Playlist this.playlist = new System.Windows.Forms.ListBox(); this.playlist.Location = new System.Drawing.Point(12, 12); this.playlist.Name = "playlist"; this.playlist.Size = new System.Drawing.Size(229, 316); this.playlist.DataSource = trackList; } private void playlist_add_Click(object sender, EventArgs e) { //Initialize OpenFileDialog OpenFileDialog opd = new OpenFileDialog(); opd.Filter = "Music (*.WAV; *.MP3; *.FLAC)|*.WAV;*.MP3;*.FLAC|All files (*.*)|*.*"; opd.Title = "Select Music"; opd.Multiselect = true; //Open OpenFileDialog if (DialogResult.OK == opd.ShowDialog()) { //Add opened files to playlist for (int i = 0; opd.FileNames.Length > i; ++i) { if (File.Exists(opd.FileNames[i])) { trackList.Add(new TAG_INFO(opd.FileNames[i])); } } //Initialize BackgroundWorker BackgroundWorker _bw = new BackgroundWorker(); _bw.WorkerReportsProgress = true; _bw.DoWork += new DoWorkEventHandler(thread_trackparser_DoWork); _bw.ProgressChanged += new ProgressChangedEventHandler(_bw_ProgressChanged); //Start ID3 extraction _bw.RunWorkerAsync(); } } void thread_trackparser_DoWork(object sender, DoWorkEventArgs e) { BackgroundWorker _bw = sender as BackgroundWorker; for (int i = 0; i < trackList.Count; ++i) { //Pass extracted tag info to _bw_ProgressChanged for thread-safe playlist entry update _bw.ReportProgress(0,new object[2] {i, BassTags.BASS_TAG_GetFromFile(trackList[i].filename)}); } } void _bw_ProgressChanged(object sender, ProgressChangedEventArgs e) { object[] unboxed = e.UserState as object[]; trackList[(int)unboxed[0]] = (unboxed[1] as TAG_INFO); } EDIT2: Much simpler test case: Try scrolling down without selecting an item. The changing ListBox will scroll to the top again. using System; using System.Windows.Forms; namespace WindowsFormsApplication1 { public class Form1 : Form { private System.ComponentModel.IContainer components = null; protected override void Dispose(bool disposing) { if (disposing && (components != null)) { components.Dispose(); } base.Dispose(disposing); } private void InitializeComponent() { this.components = new System.ComponentModel.Container(); this.listBox1 = new System.Windows.Forms.ListBox(); this.timer1 = new System.Windows.Forms.Timer(this.components); this.SuspendLayout(); // listBox1 this.listBox1.FormattingEnabled = true; this.listBox1.Location = new System.Drawing.Point(0, 0); this.listBox1.Name = "listBox1"; this.listBox1.Size = new System.Drawing.Size(200, 290); // timer1 this.timer1.Enabled = true; this.timer1.Tick += new System.EventHandler(this.timer1_Tick); // Form1 this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F); this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font; this.ClientSize = new System.Drawing.Size(200, 290); this.Controls.Add(this.listBox1); this.Name = "Form1"; this.Text = "Form1"; this.ResumeLayout(false); } private System.Windows.Forms.ListBox listBox1; private System.Windows.Forms.Timer timer1; public Form1() { InitializeComponent(); for (int i = 0; i < 45; i++) listBox1.Items.Add(i); } int tickCounter = -1; private void timer1_Tick(object sender, EventArgs e) { if (++tickCounter > 44) tickCounter = 0; listBox1.Items[tickCounter] = ((int)listBox1.Items[tickCounter])+1; } } static class Program { [STAThread] static void Main() { Application.EnableVisualStyles(); Application.SetCompatibleTextRenderingDefault(false); Application.Run(new Form1()); } } }

  Read the article

< Previous Page | 16 17 18 19 20 21 22 23 24 25 26 27  | Next Page >