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  • Why do C# automatic properties not support default values like VB 2010?

    - by Rob van Groenewoud
    Looking at the new VB 2010 features, I stumbled upon support for Auto-Implemented Properties. Since I'm working with C#, this seemed quite familiar, but I noticed that VB did add a feature I would love to have in C#: setting a arbitrary default value for the auto-implemented property: I really like the clean usage of auto-properties in C#. This would save us the effort of introducing a backing field and hooking it up to the property everytime we simply need a default value, thereby cluttering up the code unnecessarily. I was wondering why this wasn't introduced in C# as well? What could be the rationale for not doing this? Is a syntax discussion going on, or are there technical limitations to implementing this?

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  • Pass Variable to Java Method from an Ant Target

    - by user200317
    At the moment I have a .properties file to store settings related to the framework. Example: default.auth.url=http://someserver-at008:8080/ default.screenshots=false default.dumpHTML=false And I have written a class to extract those values and here is the method of that class. public static String getResourceAsStream(String defaultProp) { String defaultPropValue = null; //String keys = null; try { InputStream inputStream = SeleniumDefaultProperties.class.getClassLoader().getResourceAsStream(PROP_FILE); Properties properties = new Properties(); //load the input stream using properties. properties.load(inputStream); defaultPropValue = properties.getProperty(defaultProp); }catch (IOException e) { log.error("Something wrong with .properties file, check the location.", e); } return defaultPropValue; } Throughout the application I use method like follows to just exact property needed, public String getBrowserDefaultCommand() { String bcmd = SeleniumDefaultProperties.getResourceAsStream("default.browser.command"); if(bcmd.equals("")) handleMissingConfigProperties(SeleniumDefaultProperties.getResourceAsStream("default.browser.command")); return bcmd; } But I have not decided do a change to this and use ant and pass a parameter instead of using it from .properties file. I was wondering how could I pass a value to a Java Method using ANT. Non of these classes have Main methods and will not have any main. Due to this I was unable to use it as a java system properties. Thanks in advance.

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  • Problem prompting user for extended permissions using showPermissionDialog in FB page tab

    - by snipe
    I have an FBML app that will use the tab as a promo tab before the full app goes live. The purpose of the promo tab is to allow users to opt in to email notifications (using the FB API sendNotifications call), so I need to prompt them to allow the app and grant extended permissions on that promo tab. The tab code is: <?php require_once 'config.php'; ?> <form id="form1"> <h1> <a href="#" clickrewriteform="form1" clickrewriteurl="http://www.mydomain.com/fanpageajax/result.php" clickrewriteid="allowapp">Step 1. Allow the Application</a> </h1> <div id="allowapp"></div> </form> <h1><a onclick="Facebook.showPermissionDialog('email');return false;"> Step 2. Grant extended permissions (intab)</a></h1> The result.php page just tags the API to ensure the allow prompt will show up. The problem is with the Step 2. Once the user has allowed the app, and they click on the Step 2, nothing happens. If they click on it twice, THEN the extended permissions dialog box popups up, but it asks them to grant extended permissions TWICE. OR.... If the user clicks on Step 1, and allows the app, and then reloads the fan page tab, they only have to click on the Step 2 link once, and the permissions show up. Anyone have any ideas? I have been beating myself in the head over this for hours.

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  • Matching digits in Notepad++ extended search mode

    - by ketchup
    Notepad++'s manual is rather vague on the special character for numerical used in extended search mode. It says: \d### - Decimal value (between 000 and 255) but literally entering "\d###" doesn't match anything. What I am trying to do is to replace if VarA == 12 VarB = 1 with if VarA == 12 Var12=1 VarB=1

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  • clone of tseng et4000 extended mode font?

    - by Jason Yanowitz
    Back in the day (day =~ 1994), the tseng et4000 video card had extended modes for the console under linux. There was a beautiful monospaced font (I think it was for 100x40 or 100x50, but my memory could be wrong). Anyone know a way to get said font for a modern computer (e.g., Mac OS X) or the history of the font, etc? http://en.wikipedia.org/wiki/Tseng_ET4000 has little info on this score.

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  • Handling null values and missing object properties in Silverlight 4

    - by PeterTweed
    Before Silverlight 4 to bind a data object to the UI and display a message associated with either a null value or if the binding path was wrong, you would need to write a Converter.  In Silverlight 4 we find the addition of the markup extensions TargetNullValue and FallbackValue that allows us to display a value when a null value is found in the bound to property and display a value when the property being bound to is not found. This post will show you how to use both markup extensions. Steps: 1. Create a new Silverlight 4 application 2. In the body of the MainPage.xaml.cs file replace the MainPage class with the following code:     public partial class MainPage : UserControl     {         public MainPage()         {             InitializeComponent();             this.Loaded += new RoutedEventHandler(MainPage_Loaded);         }           void MainPage_Loaded(object sender, RoutedEventArgs e)         {             person p = new person() { NameValue = "Peter Tweed" };             this.DataContext = p;         }     }       public class person     {         public string NameValue { get; set; }         public string TitleValue { get; set; }     } This code defines a class called person with two properties.  A new instance of the class is created, only defining the value for one of the properties and bound to the DataContext of the page. 3.  In the MainPage.xaml file copy the following XAML into the LayoutRoot grid:         <Grid.RowDefinitions>             <RowDefinition Height="60*" />             <RowDefinition Height="28*" />             <RowDefinition Height="28*" />             <RowDefinition Height="30*" />             <RowDefinition Height="154*" />         </Grid.RowDefinitions>         <Grid.ColumnDefinitions>             <ColumnDefinition Width="86*" />             <ColumnDefinition Width="314*" />         </Grid.ColumnDefinitions>         <TextBlock Grid.Row="1" Height="23" HorizontalAlignment="Left" Margin="32,0,0,0" Name="textBlock1" Text="Name Value:" VerticalAlignment="Top" />         <TextBlock Grid.Row="2" Height="23" HorizontalAlignment="Left" Margin="32,0,0,0" Name="textBlock2" Text="Title Value:" VerticalAlignment="Top" />         <TextBlock Grid.Row="3" Height="23" HorizontalAlignment="Left" Margin="32,0,0,0" Name="textBlock3" Text="Non Existant Value:" VerticalAlignment="Top" />         <TextBlock Grid.Column="1" Grid.Row="1" Height="23" HorizontalAlignment="Left" Name="textBlock4" Text="{Binding NameValue, TargetNullValue='No Name!!!!!!!'}" VerticalAlignment="Top" Margin="6,0,0,0" />         <TextBlock Grid.Column="1" Grid.Row="2" Height="23" HorizontalAlignment="Left" Name="textBlock5" Text="{Binding TitleValue, TargetNullValue='No Title!!!!!!!'}" VerticalAlignment="Top" Margin="6,0,0,0" />         <TextBlock Grid.Column="1" Grid.Row="3" Height="23" HorizontalAlignment="Left" Margin="6,0,0,0" Name="textBlock6" Text="{Binding AgeValue, FallbackValue='No such property!'}" VerticalAlignment="Top" />    This XAML defines three textblocks – two of which use the TargetNull and one that uses the FallbackValue markup extensions.  4. Run the application and see the person name displayed as defined for the person object, the expected string displayed for the TargetNullValue when no value exists for the boudn property and the expected string displayed for the FallbackValue when the property bound to is not found on the bound object. It's that easy!

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  • Require extended permissions in FBML pyfacebook app

    - by jlpp
    I'm trying to get my FBML canvas page to automatically prompt new app users for permission to publish_stream. Following Facebook's documentation I tried using the required_permissions argument to require_login. That is, I tried to use the pyfacebook require_login decorator like this: @facebook.require_login(required_permissions='publish_stream') as in: @decorator_from_middleware(FacebookMiddleware) @facebook.require_login(required_permissions='publish_stream') def canvas(request, template): ... Requesting extended permissions in a pyfacebook-based Facebook iFrame app has been discussed. Requesting extended permissions in an FBML app too. My objective is to require extended permissions in an FBML app. Am I missing something or can anyone suggest a workaround? Thanks.

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  • AccessControlException: access denied - caller function failed to load properties file

    - by Michael Mao
    Hi all: I am having a jar archive environment which is gonna call my class in a folder like this: java -jar "emarket.jar" ../tournament 100 My compiled class is deployed into the ../tournament folder, this command runs well. After I changed my code to load a properties file, it gets the following exception message: Exception in thread "main" java.security.AccessControlException: access denied (java.io.FilePermission agent.properties read) at java.security.AccessControlContext.checkPermission(Unknown Source) at java.security.AccessController.checkPermission(Unknown Source) at java.lang.SecurityManager.checkPermission(Unknown Source) at java.lang.SecurityManager.checkRead(Unknown Source) at java.io.FileInputStream.<init>(Unknown Source) at java.io.FileInputStream.<init>(Unknown Source) at Agent10479475.getPropertiesFromConfigFile(Agent10479475.java:110) at Agent10479475.<init>(Agent10479475.java:100) at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source) at java.lang.reflect.Constructor.newInstance(Unknown Source) at java.lang.Class.newInstance0(Unknown Source) at java.lang.Class.newInstance(Unknown Source) at emarket.client.EmarketSandbox.instantiateClientObjects(EmarketSandbox.java:92) at emarket.client.EmarketSandbox.<init>(EmarketSandbox.java:27) at emarket.client.EmarketSandbox.main(EmarketSandbox.java:166) I am wondering why this security checking will fail. I issue the getPropertitiesFromConfigFile() function inside my class's default constructor, like this: public class Agent10479475 extends AbstractClientAgent { //default constructor public Agent10479475() { //set all properties to their default values in constructor FT_THRESHOLD = 400; FT_THRESHOLD_MARGIN = 50; printOut("Now loading properties from a config file...", ""); getPropertiesFromConfigFile(); printOut("Finished loading",""); } private void getPropertiesFromConfigFile() { Properties props = new Properties(); try { props.load(new FileInputStream("agent.properties")); FT_THRESHOLD = Long.parseLong(props.getProperty("FT_THRESHOLD")); FT_THRESHOLD_MARGIN = Long.parseLong(props.getProperty("FT_THRESHOLD_MARGIN ")); } catch(java.io.FileNotFoundException fnfex) { printOut("CANNOT FIND PROPERTIES FILE :", fnfex); } catch(java.io.IOException ioex) { printOut("IOEXCEPTION OCCURED :", ioex); } } } My class is loading its own .properties file under the same folder. why would the Java environment complains about such a denial of access? Must I config the emarket.client.EmarketSandbox class, which is not written by me and stored inside the emarket.jar, to access my agent.properties file? Any hints or suggestions is much appreciated. Many thanks in advance.

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  • php sort properties of object

    - by lannoo
    I want to sort the properties of an object so I can loop through them in a defined order. for example: I have an object 'book' with the following properties: 'id', 'title', 'author', 'date'. Now i want to loop through these properties like this: foreach($book as $prop=>$val) //do something now the order of the loop has to be 'title', then 'author', 'date' and 'id' How would one do this? (I can't change the order of the properties in the class of the object because there arent any properties defined there, I get the object from the database with 'MyActiveRecord')

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  • c++11 atomic ordering: extended total order memory_order_seq_cst for locks

    - by itaj
    There's this note in c++11 29.3-p3: [ Note: Although it is not explicitly required that S include locks, it can always be extended to an order that does include lock and unlock operations, since the ordering between those is already included in the "happens before" ordering. - end note ] What does it mean by "always"? I can understand that any certain implementation can be designed to support such an extended S. But in some general implementation that wasn't designed for it, I don't see that S can be extended so. I had sent this question to comp.std.c++ but got no answers there. http://groups.google.com/group/comp.std.c++/browse_frm/thread/5242fa70d0594d1b#

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  • MySQL Import Database Error because of Extended Inserts

    - by Castgame
    Hello all, I'm importing a 400MB(uncompressed) MySQL database. I'm using BIGDUMP, and I am getting this error: Stopped at the line 387. At this place the current query includes more than 300 dump lines. That can happen if your dump file was created by some tool which doesn't place a semicolon followed by a linebreak at the end of each query, or if your dump contains extended inserts. Please read the BigDump FAQs for more infos. I believe the file does contain Extended Inserts, however I have no way to regenerate the database as it has been deleted from the old server. How can I import this database or convert it to be imported? Thanks for any help. Best Nick EDIT: It appears the only viable answer is to separate the extended inserts, but I still need help figuring out how to split the file as the answer below suggests. Please help. Thank you.

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  • Automatic Properties, Collection Initializers, and Implicit Line Continuation support with VB 2010

    [In addition to blogging, I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu] This is the eighteenth in a series of blog posts Im doing on the upcoming VS 2010 and .NET 4 release. A few days ago I blogged about two new language features coming with C# 4.0: optional parameters and named arguments.  Today Im going to post about a few of my favorite new features being added to VB with VS 2010: Auto-Implemented Properties, Collection...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • wcf web service in post method, object properties are null, although the object is not null

    - by Abdalhadi Kolayb
    i have this problem in post method when i send object parameter to the method, then the object is not null, but all its properties have the default values. here is data module: [DataContract] public class Products { [DataMember(Order = 1)] public int ProdID { get; set; } [DataMember(Order = 2)] public string ProdName { get; set; } [DataMember(Order = 3)] public float PrpdPrice { get; set; } } and here is the interface: [OperationContract] [WebInvoke( Method = "POST", UriTemplate = "AddProduct", ResponseFormat = WebMessageFormat.Json, BodyStyle = WebMessageBodyStyle.WrappedRequest, RequestFormat = WebMessageFormat.Json)] string AddProduct([MessageParameter(Name = "prod")]Products prod); public string AddProduct(Products prod) { ProductsList.Add(prod); return "return string"; } here is the json request: Content-type:application/json {"prod":[{"ProdID": 111,"ProdName": "P111","PrpdPrice": 111}]} but in the server the object received: {"prod":[{"ProdID": 0,"ProdName": NULL,"PrpdPrice": 0}]}

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  • specific div css properties [migrated]

    - by Alecs
    I have a div : <div id="fancyboxID-1"> <p>0767380042</p> </div> and this css: ? #fancyboxID-1 p { font-size:150px; text-align: center; line-height:150px; overflow:hidden;} After I upload and refresh the website I don't see any changes but if I check the source code: I see the css properties. It's very strange for me, I've tried to upload on another server and there it works. Any ideas why this is not working ?

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  • Throwing exception from a property when my object state is invalid

    - by Rumi P.
    Microsoft guidelines say: "Avoid throwing exceptions from property getters", and I normally follow that. But my application uses Linq2SQL, and there is the case where my object can be in invalid state because somebody or something wrote nonsense into the database. Consider this toy example: [Table(Name="Rectangle")] public class Rectangle { [Column(Name="ID", IsPrimaryKey = true, IsDbGenerated = true)] public int ID {get; set;} [Column(Name="firstSide")] public double firstSide {get; set;} [Column(Name="secondSide")] public double secondSide {get; set;} public double sideRatio { get { return firstSide/secondSide; } } } Here, I could write code which ensures that my application never writes a Rectangle with a zero-length side into the database. But no matter how bulletproof I make my own code, somebody could open the database with a different application and create an invalid Rectangle, especially one with a 0 for secondSide. (For this example, please forget that it is possible to design the database in a way such that writing a side length of zero into the rectangle table is impossible; my domain model is very complex and there are constraints on model state which cannot be expressed in a relational database). So, the solution I am gravitating to is to change the getter to: get { if(firstSide > 0 && secondSide > 0) return firstSide/secondSide; else throw new System.InvalidOperationException("All rectangle sides should have a positive length"); } The reasoning behind not throwing exceptions from properties is that programmers should be able to use them without having to make precautions about catching and handling them them. But in this case, I think that it is OK to continue to use this property without such precautions: if the exception is thrown because my application wrote a non-zero rectangle side into the database, then this is a serious bug. It cannot and shouldn't be handled in the application, but there should be code which prevents it. It is good that the exception is visibly thrown, because that way the bug is caught. if the exception is thrown because a different application changed the data in the database, then handling it is outside of the scope of my application. So I can't do anything about it if I catch it. Is this a good enough reasoning to get over the "avoid" part of the guideline and throw the exception? Or should I turn it into a method after all? Note that in the real code, the properties which can have an invalid state feel less like the result of a calculation, so they are "natural" properties, not methods.

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  • gnome-file-share-properties doesn't work

    - by Riccardo Magrini
    I've configured gnome-file-share-properties on all my Ubuntu's PC for sharing the directory Public to each other. I following some guide found on Internet for the configuration of it, all explain the same procedure but in my case I don't see any Public directory shared with the PC. Following this link http://library.gnome.org/users/gnome-user-share/stable/gnome-user-share-getting-started.html.en I'd see the directory Public plus the name of PC that shares its directory on Nautilus Places. In my case I don't see anything, therefore on the Network place see all the machines 'n if I try to click on one receive this: "DBus error org.freedesktop.DBus.Error.NoReply: Message did not receive a reply (timeout by message bus)" note: I don't want to use Samba because I've all Ubuntu PC, and the firewall is disabled on all PC.

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  • Syncing properties across a game server

    - by Vaughan Hilts
    I'm beginning to implement a simple scripting system into my networked server, and I've hit a snag. Before, I've been wrapping my calls into functions on objects that manipulate objects, but lately I've been finding this to be a pain for simple things. For example, if I set 'player.HP = 1'.. this works server-side. But the player side never sees this change unless I explicitly send a packet to inform the client. For many things like map swapping that require more complicated changes, like change X, Y, Map and do this.. I have a function. That's fine. But what about these small properties I want to sync?

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  • Multiple parameters vs single parameter(object with multiple properties)

    - by Shwetanka
    I have an Entity Student with following properties - (name, joinedOn, birthday, age, batch, etc.) and a function fetchStudents(<params>). I want to fetch students based on multiple filters. In my method I have two ways to pass filters. Pass all filters as params to the method Make a class StudentCriteria with filters as fields and then pass the object of this class While working in java I always go with the second option but recently I'm working in php and I was advised to go with the first way. I am unable to figure out which way is better in maintaining the code, reusability and performance wise. Thanks.

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  • Extended URL php

    - by web.ask
    I have a problem with the extended url here in php. I'm not even sure if it's called extended url. I was wondering if someone can help me since i'm no good with PHP. I have a php page the careers.php it shows the career listing but when I click on Learn more link it goes to http(dot)localhost/houseofpatel/jobs/4/Career-4 but it outputs an "Object not found". Does xampplite have something to do with this? or is it just the codes? I also have the breadcrumb.php in here. Please see code below: session_start(); include("Breadcrumb.php"); $trail = new Breadcrumb(); $trail->add('Careers', $_SERVER['PHP_SELF'], 1); $trail -> output(); # REMOVE SPECIAL CHARACTERS $sPattern = array('/[^a-zA-Z0-9 -]/', '/[ -]+/', '/^-|-$/'); $sReplace = array('', '-', ''); mysql_query("SET CHARACTER_SET utf8"); //$query = "SELECT * FROM careers_mst WHERE status = 1 ORDER BY dateposted DESC LIMIT 0, 4"; if(!$_GET['jobs']){ $jobsPerPage = 4; }else{ $jobsPerPage = $_GET['jobs']; } if(!$_GET['page']){ $currPage = 1; $showMoreJobs = true; }else{ $currPage = $_GET['page']; $showMoreJobs = false; } $offset = ($currPage - 1 )* $jobsPerPage; $query = "SELECT * FROM careers_mst WHERE status = 1 ORDER BY dateposted"; $process = mysql_query($query); if(@mysql_num_rows($process) > 0){ $totalRows = @mysql_num_rows($process); $query2 = "SELECT * FROM careers_mst WHERE status = 1 ORDER BY dateposted DESC LIMIT $offset, $jobsPerPage"; $process2 = mysql_query($query2); if(@mysql_num_rows($process2) > 0){ $pagNav = pageNavigator($totalRows,$jobsPerPage,$currPage,''); while($row = @mysql_fetch_array($process2)){ $id = $row[0]; $title = stripslashes($row['title']); $title1 = preg_replace($sPattern, $sReplace, $title); $description = stripslashes($row['description']); $description1 = substr($description, 0, 200); $careers_list .= ' <div class="left" style="width:340px; padding-left:10px;"> <p><span class="blue"><strong>'.$title.'</strong></span></p> '.$description1.'... <p><a href="jobs/'.$id.'/'.$title1.'" title="Learn more">[ Learn More ]</a></p> </div>'; } /*$careers_list .= ' <div class="left" style="width: 100%; margin-top:15px;"> <p><a href="more-jobs" title="More Job Opennings">MORE JOB OPENNINGS >> </a></p> <div class="divider left"></div> </div>'; */ if($showMoreJobs){ if($totalRows > $jobsPerPage){ $currPage++; } $jobNav = "<a href=careers.php?page=$currPage title='More Job Opennings'>MORE JOB OPENNINGS >> </a>"; }else{ $jobNav = "$pagNav"; } $careers_list .= "<div class='left' style='width: 100%; margin-top:15px;'> <p>$jobNav</p> <div class='divider left'></div> </div>"; } }

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  • The best, in the West

    - by Fatherjack
    As many of you know, I run the SQL South West user group and we are currently in full flow preparing to stage the UK’s second SQL Saturday. The SQL Saturday spotlight is going to fall on Exeter in March 2013. We have full-day session on Friday 8th with some truly amazing speakers giving their insights and experience into some vital areas of working with SQL Server: Dave Ballantyne and Dave Morrison – TSQL and internals Christian Bolton and Gavin Payne – Mission critical data platforms on Windows Server 2012 Denny Cherry – SQL Server Security André Kamman – Powershell 3.0 for SQL Server Administrators and Developers Mladen Prajdic – From SQL Traces to Extended Events – The next big switch. A number of people have claimed that the choice is too good and they’d have trouble selecting just one session to attend. I can see how this is a problem but hope that they make their minds up quickly. The venue is a bespoke conference suite in the centre of Exeter but has limited capacity so we are working on a first-come first-served basis. All the session details and booking and travel information can be found on our user group website. The Saturday will be a day of free, 50 minute sessions on all aspects SQL Server from almost 30 different speakers. If you would like to submit a session then get a move on as submissions close on 8th January 2013 (That’s less than a month away). We are really interested in getting new speakers started so we have a lightning talk session where you can come along and give a small talk (anywhere from 5 to 15 minutes long) about anything connected with SQL Server as a way to introduce you to what it’s like to be a speaker at an event. Details on registering to attend and to submit a session (Lightning talks need to be submitted too please) can be found on our SQL Saturday pages. This is going to be the biggest and best bespoke SQL Server conference to ever take place this far South West in the UK and we aim to give everyone who comes to either day a real experience of the South West so we have a few surprises for you on the day.

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  • Custom Model Binding of IEnumerable Properties in ASP.Net MVC 2

    - by Doug Lampe
    MVC 2 provides a GREAT feature for dealing with enumerable types.  Let's say you have an object with a parent/child relationship and you want to allow users to modify multiple children at the same time.  You can simply use the following syntax for any indexed enumerables (arrays, generic lists, etc.) and then your values will bind to your enumerable model properties. 1: <% using (Html.BeginForm("TestModelParameter", "Home")) 2: { %> 3: < table > 4: < tr >< th >ID</th><th>Name</th><th>Description</th></tr> 5: <% for (int i = 0; i < Model.Items.Count; i++) 6: { %> 7: < tr > 8: < td > 9: <%= i %> 10: </ td > 11: < td > 12: <%= Html.TextBoxFor(m => m.Items[i].Name) %> 13: </ td > 14: < td > 15: <%= Model.Items[i].Description %> 16: </ td > 17: </ tr > 18: <% } %> 19: </ table > 20: < input type ="submit" /> 21: <% } %> Then just update your model either by passing it into your action method as a parameter or explicitly with UpdateModel/TryUpdateModel. 1: public ActionResult TestTryUpdate() 2: { 3: ContainerModel model = new ContainerModel(); 4: TryUpdateModel(model); 5:   6: return View("Test", model); 7: } 8:   9: public ActionResult TestModelParameter(ContainerModel model) 10: { 11: return View("Test", model); 12: } Simple right?  Well, not quite.  The problem is the DefaultModelBinder and how it sets properties.  In this case our model has a property that is a generic list (Items).  The first bad thing the model binder does is create a new instance of the list.  This can be fixed by making the property truly read-only by removing the set accessor.  However this won't help because this behaviour continues.  As the model binder iterates through the items to "set" their values, it creates new instances of them as well.  This means you lose any information not passed via the UI to your controller so in the examplel above the "Description" property would be blank for each item after the form posts. One solution for this is custom model binding.  I have put together a solution which allows you to retain the structure of your model.  Model binding is a somewhat advanced concept so you may need to do some additional research to really understand what is going on here, but the code is fairly simple.  First we will create a binder for the parent object which will retain the state of the parent as well as some information on which children have already been bound. 1: public class ContainerModelBinder : DefaultModelBinder 2: { 3: /// <summary> 4: /// Gets an instance of the model to be used to bind child objects. 5: /// </summary> 6: public ContainerModel Model { get; private set; } 7:   8: /// <summary> 9: /// Gets a list which will be used to track which items have been bound. 10: /// </summary> 11: public List<ItemModel> BoundItems { get; private set; } 12:   13: public ContainerModelBinder() 14: { 15: BoundItems = new List<ItemModel>(); 16: } 17:   18: protected override object CreateModel(ControllerContext controllerContext, ModelBindingContext bindingContext, Type modelType) 19: { 20: // Set the Model property so child binders can find children. 21: Model = base.CreateModel(controllerContext, bindingContext, modelType) as ContainerModel; 22:   23: return Model; 24: } 25: } Next we will create the child binder and have it point to the parent binder to get instances of the child objects.  Note that this only works if there is only one property of type ItemModel in the parent class since the property to find the item in the parent is hard coded. 1: public class ItemModelBinder : DefaultModelBinder 2: { 3: /// <summary> 4: /// Gets the parent binder so we can find objects in the parent's collection 5: /// </summary> 6: public ContainerModelBinder ParentBinder { get; private set; } 7: 8: public ItemModelBinder(ContainerModelBinder containerModelBinder) 9: { 10: ParentBinder = containerModelBinder; 11: } 12:   13: protected override object CreateModel(ControllerContext controllerContext, ModelBindingContext bindingContext, Type modelType) 14: { 15: // Find the item in the parent collection and add it to the bound items list. 16: ItemModel item = ParentBinder.Model.Items.FirstOrDefault(i => !ParentBinder.BoundItems.Contains(i)); 17: ParentBinder.BoundItems.Add(item); 18: 19: return item; 20: } 21: } Finally, we will register these binders in Global.asax.cs so they will be used to bind the classes. 1: protected void Application_Start() 2: { 3: AreaRegistration.RegisterAllAreas(); 4:   5: ContainerModelBinder containerModelBinder = new ContainerModelBinder(); 6: ModelBinders.Binders.Add(typeof(ContainerModel), containerModelBinder); 7: ModelBinders.Binders.Add(typeof(ItemModel), new ItemModelBinder(containerModelBinder)); 8:   9: RegisterRoutes(RouteTable.Routes); 10: } I'm sure some of my fellow geeks will comment that this could be done more efficiently by simply rewriting some of the methods of the default model binder to get the same desired behavior.  I like my method shown here because it extends the binder class instead of modifying it so it minimizes the potential for unforseen problems. In a future post (if I ever get around to it) I will explore creating a generic version of these binders.

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