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  • MVC: capture route url's and pass them to javascript function

    - by Tim Geerts
    Short:Is there a way to have a route-definition that will pass the "CONTROLLER/ACTION" string value to a javascript function in stead of actually going straight for the controller action? More:I have a masterpage which contains the navigation of the site. Now, all the pages need this navigation wrapped around it at all times, but because I didn't want the navigation to constantly load with each pagecall, I changed all my pages to partialviews. These partial views are loaded via the JQuery.Load() method whenever a menu item is clicked in the navigation. This all worked very good, up till now because I noticed it's also a requirement of the website to be able to link directly to page X, rather then default.aspx. So, as an example:The main page is my "default.aspx" page, this utilizes my master page with the nagivation around it. And each call to a new page uses a javascript function that loads that particular partial view inside a div that is known in my masterpage. So, the url never changes away from "default.aspx", but my content changes seemlesly. The problem is, those url's also need to be available when typed directly into the address bar. But, they're partial views, so loading them directly from the address bar makes them display without any masterpages around them. Therefore my question if it might be possible to capture the route typed into the address bar and pass that on to my javascript function that will load that route in the content div. (I hope I explained it ok enough, if not, feel free to ask more information)

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  • Ninject InThreadScope Binding

    - by e36M3
    I have a Windows service that contains a file watcher that raises events when a file arrives. When an event is raised I will be using Ninject to create business layer objects that inside of them have a reference to an Entity Framework context which is also injected via Ninject. In my web applications I always used InRequestScope for the context, that way within one request all business layer objects work with the same Entity Framework context. In my current Windows service scenario, would it be sufficient to switch the Entity Framework context binding to a InThreadScope binding? In theory when an event handler in the service triggers it's executed under some thread, then if another file arrives simultaneously it will be executing under a different thread. Therefore both events will not be sharing an Entity Framework context, in essence just like two different http requests on the web. One thing that bothers me is the destruction of these thread scoped objects, when you look at the Ninject wiki: .InThreadScope() - One instance of the type will be created per thread. .InRequestScope() - One instance of the type will be created per web request, and will be destroyed when the request ends. Based on this I understand that InRequestScope objects will be destroyed (garbage collected?) when (or at some point after) the request ends. This says nothing however on how InThreadScope objects are destroyed. To get back to my example, when the file watcher event handler method is completed, the thread goes away (back to the thread pool?) what happens to the InThreadScope-d objects that were injected? EDIT: One thing is clear now, that when using InThreadScope() it will not destroy your object when the handler for the filewatcher exits. I was able to reproduce this by dropping many files in the folder and eventually I got the same thread id which resulted in the same exact Entity Framework context as before, so it's definitely not sufficient for my applications. In this case a file that came in 5 minutes later could be using a stale context that was assigned to the same thread before.

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  • Filter elements in PropertyGrid

    - by serhio
    In System.Windows.Forms there are a PropertyGrid that displays properties of an attached object. Let's say MyTextBox : TextBox. Now, I would like to display on it some MyTextBox properties, say only Size, Location and my custom property Date. More that than, I would like to be able to change the real property names, say "Dimension", "Location" and "Starting Date". I saw two projects on this subject : first and second, but first does not work well(for browsable properties), and the second seems to add an event for each property changes, this is not acceptable.

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  • How to determine the path of the current web site

    - by Velika2
    I wanted to create a function which would return the path of the current web site. This is what I thought was working while running in the IDE: Public Shared Function WebsiteAbsoluteBaseUrl() As String Dim RequestObject As System.Web.HttpRequest = HttpContext.Current.Request Return "http://" & RequestObject.Url.Host & ":" & _ RequestObject.Url.Port & "/" & _ RequestObject.Url.Segments(1) End Function Does this seem like it should work? Is there a more straight forward way?

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  • Is this a good way to expose generic base class methods through an interface?

    - by Nate Heinrich
    I am trying to provide an interface to an abstract generic base class. I want to have a method exposed on the interface that consumes the generic type, but whose implementation is ultimately handled by the classes that inherit from my abstract generic base. However I don't want the subclasses to have to downcast to work with the generic type (as they already know what the type should be). Here is a simple version of the only way I can see to get it to work at the moment. public interface IFoo { void Process(Bar_base bar); } public abstract class FooBase<T> : IFoo where T : Bar_base { abstract void Process(T bar); // Explicit IFoo Implementation void IFoo.Process(Bar_base bar) { if (bar == null) throw new ArgumentNullException(); // Downcast here in base class (less for subclasses to worry about) T downcasted_bar = bar as T; if (downcasted_bar == null) { throw new InvalidOperationException( string.Format("Expected type '{0}', not type '{1}'", T.ToString(), bar.GetType().ToString()); } //Process downcasted object. Process(downcasted_bar); } } Then subclasses of FooBase would look like this... public class Foo_impl1 : FooBase<Bar_impl1> { void override Process(Bar_impl1 bar) { //No need to downcast here! } } Obviously this won't provide me compile time Type Checking, but I think it will get the job done... Questions: 1. Will this function as I think it will? 2. Is this the best way to do this? 3. What are the issues with doing it this way? 4. Can you suggest a different approach? Thanks!

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  • multiple calender in exchange web service

    - by user3559462
    i have multiple calender in my mailbox, i can retrieve only one calender that is main calnder folder using ews api 2.0, now i want whole list of calenders and appointments and meetings in that. like i have three calender one is main calnder 1.Calender(color-code:default) 2.Jorgen(color-code:pink) 3.Soren(color-code: yellow) i can retrieve all the values of main "Calnder", using the below code Folder inbox = Folder.Bind(service, WellKnownFolderName.Calendar); view.PropertySet = new PropertySet(BasePropertySet.IdOnly); // This results in a FindItem call to EWS. FindItemsResults<Item> results = inbox.FindItems(view); i = 1; m = results.TotalCount; if (results.Count() > 0) { foreach (var item in results) { PropertySet props = new PropertySet(AppointmentSchema.MimeContent,AppointmentSchema.ParentFolderId,AppointmentSchema.Id,AppointmentSchema.Categories,AppointmentSchema.Location); // This results in a GetItem call to EWS. var email = Appointment.Bind(service, item.Id, props); string iCalFileName = @"C:\export\appointment" +i ".ics"; // Save as .eml. using (FileStream fs = new FileStream(iCalFileName, FileMode.Create, FileAccess.Write)) { fs.Write(email.MimeContent.Content, 0, email.MimeContent.Content.Length); } i++; } now i want to get all the remaining calender schedules also, i am not able to get is Please help, need it urgently

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  • adding users, membership, and roles to site

    - by Alexander
    I have followed scott's gu tutorial here I uploaded the whole database to my site. Before doing what Scott's says I had one username stored in the membership. How can I create an additional user now that the table is in the web host? I can see that there's aspnet_Membership, aspnet_Applications, etc..etc

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  • IValidator.Validate method and adding error message to a custom type

    - by user102533
    I have several server controls that implement the IValidator interface. As such, they have their own Validate() methods that look like this. public void Validate() { this.IsValid = true; if (someConditionFails()) { ErrorMessage = "Condition failed!"; this.IsValid = false; } } I understand that these Validate() methods are executed on postback before the load completed event that is executed before the save button's event handler. What I would like to do is pass in a reference to an instance of a custom class that collects all the error messages that I can access from Save button event handler. In other words, I would like to do something like this: public void Validate(ref SummaryOfErrorMessages sum) I guess I can't do this as the signature is different from what the IValidator interface has. The other option I can think of is on Load Completed event, I would iterate through all the validators on page, get the ones with IsValid = false and create my SummaryOfErrorMessages there. Does this sound right? Is there a better way of doing it?

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  • How to fire server-side methods with jQuery

    - by Nasser Hajloo
    I have a large application and I'm going to enabling short-cut key for it. I'd find 2 JQuery plug-ins (demo plug-in 1 - Demo plug-in 2) that do this for me. you can find both of them in this post in StackOverFlow My application is a completed one and I'm goining to add some functionality to it so I don't want towrite code again. So as a short-cut is just catching a key combination, I'm wonder how can I call the server methods which a short-cut key should fire? So How to use either of these plug-ins, by just calling the methods I'd written before? Actually How to fire Server methods with Jquery? You can also find a good article here, by Dave Ward Update: here is the scenario. When User press CTRL+Del the GridView1_OnDeleteCommand so I have this protected void grdDocumentRows_DeleteCommand(object source, System.Web.UI.WebControls.DataGridCommandEventArgs e) { try { DeleteRow(grdDocumentRows.DataKeys[e.Item.ItemIndex].ToString()); clearControls(); cmdSaveTrans.Text = Hajloo.Portal.Common.Constants.Accounting.Documents.InsertClickText; btnDelete.Visible = false; grdDocumentRows.EditItemIndex = -1; BindGrid(); } catch (Exception ex) { Page.AddMessage(GetLocalResourceObject("AProblemAccuredTryAgain").ToString(), MessageControl.TypeEnum.Error); } } private void BindGrid() { RefreshPage(); grdDocumentRows.DataSource = ((DataSet)Session[Hajloo.Portal.Common.Constants.Accounting.Session.AccDocument]).Tables[AccDocument.TRANSACTIONS_TABLE]; grdDocumentRows.DataBind(); } private void RefreshPage() { Creditors = (decimal)((AccDocument)Session[Hajloo.Portal.Common.Constants.Accounting.Session.AccDocument]).Tables[AccDocument.ACCDOCUMENT_TABLE].Rows[0][AccDocument.ACCDOCUMENT_CREDITORS_SUM_FIELD]; Debtors = (decimal)((AccDocument)Session[Hajloo.Portal.Common.Constants.Accounting.Session.AccDocument]).Tables[AccDocument.ACCDOCUMENT_TABLE].Rows[0][AccDocument.ACCDOCUMENT_DEBTORS_SUM_FIELD]; if ((Creditors - Debtors) != 0) labBalance.InnerText = GetLocalResourceObject("Differentiate").ToString() + "?" + (Creditors - Debtors).ToString(Hajloo.Portal.Common.Constants.Common.Documents.CF) + "?"; else labBalance.InnerText = GetLocalResourceObject("Balance").ToString(); lblSumDebit.Text = Debtors.ToString(Hajloo.Portal.Common.Constants.Common.Documents.CF); lblSumCredit.Text = Creditors.ToString(Hajloo.Portal.Common.Constants.Common.Documents.CF); if (grdDocumentRows.EditItemIndex == -1) clearControls(); } Th other scenario are the same. How to enable short-cut for these kind of code (using session , NHibernate, etc)

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  • writing a data to App_Data

    - by Alexander
    I want to write an .xml file using the following code into the App_Data/posts, why is it causing an error: Stream writer = new FileStream("..'\'App_Data'\'posts'\'" + new Guid(post_ID.ToString()).ToString() + ".xml", FileMode.Create);

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  • Random String Generator creates same string on multiple calls

    - by rockinthesixstring
    Hi there. I've build a random string generator but I'm having a problem whereby if I call the function multiple times say in a Page_Load method, the function returns the same string twice. here's the code ''' <summary>' ''' Generates a Random String' ''' </summary>' ''' <param name="n">number of characters the method should generate</param>' ''' <param name="UseSpecial">should the method include special characters? IE: # ,$, !, etc.</param>' ''' <param name="SpecialOnly">should the method include only the special characters and excludes alpha numeric</param>' ''' <returns>a random string n characters long</returns>' Public Function GenerateRandom(ByVal n As Integer, Optional ByVal UseSpecial As Boolean = True, Optional ByVal SpecialOnly As Boolean = False) As String Dim chars As String() ' a character array to use when generating a random string' Dim ichars As Integer = 74 'number of characters to use out of the chars string' Dim schars As Integer = 0 ' number of characters to skip out of the characters string' chars = { _ "A", "B", "C", "D", "E", "F", _ "G", "H", "I", "J", "K", "L", _ "M", "N", "O", "P", "Q", "R", _ "S", "T", "U", "V", "W", "X", _ "Y", "Z", "0", "1", "2", "3", _ "4", "5", "6", "7", "8", "9", _ "a", "b", "c", "d", "e", "f", _ "g", "h", "i", "j", "k", "l", _ "m", "n", "o", "p", "q", "r", _ "s", "t", "u", "v", "w", "x", _ "y", "z", "!", "@", "#", "$", _ "%", "^", "&", "*", "(", ")", _ "-", "+"} If Not UseSpecial Then ichars = 62 ' only use the alpha numeric characters out of "char"' If SpecialOnly Then schars = 62 : ichars = 74 ' skip the alpha numeric characters out of "char"' Dim rnd As New Random() Dim random As String = String.Empty Dim i As Integer = 0 While i < n random += chars(rnd.[Next](schars, ichars)) System.Math.Max(System.Threading.Interlocked.Increment(i), i - 1) End While rnd = Nothing Return random End Function but if I call something like this Dim str1 As String = GenerateRandom(5) Dim str2 As String = GenerateRandom(5) the response will be something like this g*3Jq g*3Jq and the second time I call it, it will be 3QM0$ 3QM0$ What am I missing? I'd like every random string to be generated as unique.

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  • Covariance and Contravariance inference in C# 4.0

    - by devoured elysium
    When we define our interfaces in C# 4.0, we are allowed to mark each of the generic parameters as in or out. If we try to set a generic parameter as out and that'd lead to a problem, the compiler raises an error, not allowing us to do that. Question: If the compiler has ways of inferring what are valid uses for both covariance (out) and contravariance(in), why do we have to mark interfaces as such? Wouldn't it be enough to just let us define the interfaces as we always did, and when we tried to use them in our client code, raise an error if we tried to use them in an un-safe way? Example: interface MyInterface<out T> { T abracadabra(); } //works OK interface MyInterface2<in T> { T abracadabra(); } //compiler raises an error. //This makes me think that the compiler is cappable //of understanding what situations might generate //run-time problems and then prohibits them. Also, isn't it what Java does in the same situation? From what I recall, you just do something like IMyInterface<? extends whatever> myInterface; //covariance IMyInterface<? super whatever> myInterface2; //contravariance Or am I mixing things? Thanks

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  • How do I use a spark variable in an html helper?

    - by Quintin Par
    Can I use a spark variable inside an html helper? Say we have <var url="Url.Action(“get”)" /> !{Html.Image("~/Content/up.png")} Now if I need to use the url inside Html.Image as an attribute(part of the 2nd param) to get <img src="~/Content/up.png" type="~/engine/get" /> how do I go about doing it?

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  • How can i query for null values in entity framework?

    - by AZ
    I want to execute a query like this var result = from entry in table where entry.something == null select entry; and get an IS NULL generated. Edited: After the first two answers i feel the need to clarify that I'm using Entity Framework and not Linq to SQL. The object.Equals() method does not seem to work in EF. Edit no.2: The above query works as intended. It correctly generates IS NULL. My production code however was var value = null; var result = from entry in table where entry.something == value select entry; and the generated SQL was something = @p; @p = NULL. It seems that EF correctly translates the constant expression but if a variable is involved it treats it just like a normal comparison. Makes sense actually. I'll close this question

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  • problems with a jquery plugin

    - by CoffeeCode
    I'm using AJAX_POSTUP. When i make a request it sends a file to a bowser [offers to download] (the files content are params of the action methods). Does anyone know whats going on and how i can avoid this problem??? i'm not aware of other plugins such as AJAX_POSTUP

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  • Advice on designing and building distributed application to track vehicles

    - by dario-g
    I'm working on application for tracking vehicles. There will be about 10k or more vehicles. Each will be sending ~250bytes in each minute. Data contains gps location and everything from CAN Bus (every data that we can read from vehicle computer and dashboard). Data are sent by GSM/GPRS (using UDP protocol). Estimated rows with this data per day is ~2000k. I see there 3 main blocks. 1. Multithreaded Socket Server (MSS) - I have it. MSS stores received data to the queue (using NServiceBus). 2. Rule Processor Server (RPS) - this is core of this system. This block is responsible for parsing received data, storing in the database, processing rules, sending messages to Notifier Server (this will be sending e-mails/sms texts). Rule example. As I said between received bytes there will be information about current speed. When speed will be above 120 then: show alert in web application for specified users, send e-mail, send sms text. (There can be more than one instance of RPS). 3. Web application - allows reporting and defining rules by users, monitoring alerts, etc. I'm looking for advice how to design communication between RPS and Web application. Some questions: - Should Web application and RPS have separated databases or one central database will be enough? I have one domain model in web application. If there will be one central database then can I use the same model (objects) on RPS? So, how to send changed rules to RPS? I try to decouple this blocks as much as possible. I'm planning to create different instance of application for each client (each client will have separated database). One client will be have 10k vehicles, others only 100 vehicles.

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  • Problems using FluentNHibernate + SQLite with .NET4?

    - by stiank81
    I have a WPF application running with VS2010 .Net3.5 using Nhibernate with FluentNHibernate + SQLite, and all works fine. Now I want to change to use .Net4, but this has turned into a more painful experience then I expected.. When setting up the connection a FluentConfigurationException is thrown from FluentConfiguration.BuildConfiguration saying: An invalid or incomplete configuration was used while creating a SessionFactory. Check PotentialReasons collection, and InnerException for more details. The inner exception gives us more information: Could not create the driver from NHibernate.Driver.SQLite20Driver, NHibernate, Version=2.1.2.4000, Culture=neutral, PublicKeyToken=aa95f207798dfdb4. It has an InnerException again: Exception has been thrown by the target of an invocation. Which again has an InnerException: The IDbCommand and IDbConnection implementation in the assembly System.Data.SQLite could not be found. Ensure that the assembly System.Data.SQLite is located in the application directory or in the Global Assembly Cache. If the assembly is in the GAC, use element in the application configuration file to specify the full name of the assembly. Now - to me it sounds like it doesn't find System.Data.SQLite.dll, but I can't understand this. Everywhere this is referenced I have "Copy Local", and I have verified that it is in every build folder for projects using SQLite. I have also copied it manually to every Debug folder of the solution - without luck. Notes: This is exactly the same code that worked just fine before I upgraded to .Net4. I did see some x64 x86 mismatch problems earlier, but I have switched to use x86 as the target platform and for all referenced dlls. I have verified that all files in the Debug-folder are x86. I have tried the precompiled Fluent dlls, I have tried compiling myself, and I have compiled my own version of Fluent using .Net4. I see that there are also others that have seen this problem, but I haven't really seen any solution yet. After @devio's answer I tried adding a reference to the SQLite dll. This didn't change anything, but I hope I made it right though.. This is what I added to the root node of the app.config file: <runtime> <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1"> <qualifyAssembly partialName="System.Data.SQLite" fullName="System.Data.SQLite, Version=1.0.60.0, Culture=neutral, PublicKeyToken=db937bc2d44ff139" /> </assemblyBinding> </runtime> Anyone out there using Fluent with .Net4 and SQLite successfully? Help! I'm lost...

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  • ASP Calendar Date Pick

    - by Steven
    I am attempting to construct my own date picker using code from several sources. Specifically, I am now populating the textbox with a calendar click. Two questions: Why does the first click refresh the page without doing anything? How can I have the textbox update without refreshing the entire page? myDate.ascx <%@ Control Language="vb" AutoEventWireup="false" CodeBehind="myDate.ascx.vb" Inherits="Website.myDate" %> <script language="javascript" type="text/javascript"> function toggleCalendar(myID) { var obj = document.getElementById(myID) obj.style.display = (obj.style.display == "none") ? "" : "none"; } </script> <asp:TextBox ID="dateText" runat="server" > </asp:TextBox> <input type="button" name="dateBtn" value="x" onclick="toggleCalendar('<%=dateCal.clientID%>');" /> <asp:Calendar ID="dateCal" runat="server" ></asp:Calendar> myDate.ascx.vb Partial Public Class myDate Inherits System.Web.UI.UserControl Protected Sub dateCal_SelectionChanged _ (ByVal sender As Object, ByVal e As EventArgs) _ Handles dateCal.SelectionChanged dateText.Text = dateCal.SelectedDate 'update text box' dateCal.Style("display") = "none" 'hide calendar' End Sub End Class

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  • Getting the constructor of an Interface Type through reflection, is there a better approach than loo

    - by Will Marcouiller
    I have written a generic type: IDirectorySource<T> where T : IDirectoryEntry, which I'm using to manage Active Directory entries through my interfaces objects: IGroup, IOrganizationalUnit, IUser. So that I can write the following: IDirectorySource<IGroup> groups = new DirectorySource<IGroup>(); // Where IGroup implements `IDirectoryEntry`, of course.` foreach (IGroup g in groups.ToList()) { listView1.Items.Add(g.Name).SubItems.Add(g.Description); } From the IDirectorySource<T>.ToList() methods, I use reflection to find out the appropriate constructor for the type parameter T. However, since T is given an interface type, it cannot find any constructor at all! Of course, I have an internal class Group : IGroup which implements the IGroup interface. No matter how hard I have tried, I can't figure out how to get the constructor out of my interface through my implementing class. [DirectorySchemaAttribute("group")] public interface IGroup { } internal class Group : IGroup { internal Group(DirectoryEntry entry) { NativeEntry = entry; Domain = NativeEntry.Path; } // Implementing IGroup interface... } Within the ToList() method of my IDirectorySource<T> interface implementation, I look for the constructor of T as follows: internal class DirectorySource<T> : IDirectorySource<T> { // Implementing properties... // Methods implementations... public IList<T> ToList() { Type t = typeof(T) // Let's assume we're always working with the IGroup interface as T here to keep it simple. // So, my `DirectorySchema` property is already set to "group". // My `DirectorySearcher` is already instantiated here, as I do it within the DirectorySource<T> constructor. Searcher.Filter = string.Format("(&(objectClass={0}))", DirectorySchema) ConstructorInfo ctor = null; ParameterInfo[] params = null; // This is where I get stuck for now... Please see the helper method. GetConstructor(out ctor, out params, new Type() { DirectoryEntry }); SearchResultCollection results = null; try { results = Searcher.FindAll(); } catch (DirectoryServicesCOMException ex) { // Handling exception here... } foreach (SearchResult entry in results) entities.Add(ctor.Invoke(new object() { entry.GetDirectoryEntry() })); return entities; } } private void GetConstructor(out ConstructorInfo constructor, out ParameterInfo[] parameters, Type paramsTypes) { Type t = typeof(T); ConstructorInfo[] ctors = t.GetConstructors(BindingFlags.CreateInstance | BindingFlags.NonPublic | BindingFlags.Public | BindingFlags.InvokeMethod); bool found = true; foreach (ContructorInfo c in ctors) { parameters = c.GetParameters(); if (parameters.GetLength(0) == paramsTypes.GetLength(0)) { for (int index = 0; index < parameters.GetLength(0); ++index) { if (!(parameters[index].GetType() is paramsTypes[index].GetType())) found = false; } if (found) { constructor = c; return; } } } // Processing constructor not found message here... } My problem is that T will always be an interface, so it never finds a constructor. Is there a better way than looping through all of my assembly types for implementations of my interface? I don't care about rewriting a piece of my code, I want to do it right on the first place so that I won't need to come back again and again and again. EDIT #1 Following Sam's advice, I will for now go with the IName and Name convention. However, is it me or there's some way to improve my code? Thanks! =)

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  • C# to Java: where T : new() Syntax

    - by Shiftbit
    I am porting some C# code over to Java. I am having trouble with the where Syntax, specifically new(). I understand that where is similar to Java's generic: T extends FOO. How I can replicate the new() argument in Java? "The new() Constraint lets the compiler know that any type argument supplied must have an accessible parameterless--or default-- constructor." - MSDN ie: public class BAR<T> : BAR where T : FOO, new() Right now I have: public class BAR<T extends FOO> extends ABSTRACTBAR { public HXIT(T t){ this.value = t; } .... }

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  • click event launched only once problem

    - by user281180
    I have a form in which I have many checkboxes. I need to post the data to the controller upon any checkbox checked or unchecked, i.e a click on a checbox must post to the controller, and there is no submit button. What will be the bet method in this case? I have though of Ajax.BeginForm and have the codes below. The problem im having is that the checkbox click event is being detected only once and after that the click event isnt being launched. Why is that so? How can I correct that? <% using (Ajax.BeginForm("Edit", new AjaxOptions { UpdateTargetId = "tests"})) {%> <div id="tests"> <%Html.RenderPartial("Details", Model); %> </div> <input type="submit" value="Save" style="Viibility:hidden" id="myForm"/> <%} %> $(function() { $('input:checkbox').click(function() { $('#myForm').click(); }); });

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  • Approaches for generic, compile-time safe lazy-load methods

    - by Aaronaught
    Suppose I have created a wrapper class like the following: public class Foo : IFoo { private readonly IFoo innerFoo; public Foo(IFoo innerFoo) { this.innerFoo = innerFoo; } public int? Bar { get; set; } public int? Baz { get; set; } } The idea here is that the innerFoo might wrap data-access methods or something similarly expensive, and I only want its GetBar and GetBaz methods to be invoked once. So I want to create another wrapper around it, which will save the values obtained on the first run. It's simple enough to do this, of course: int IFoo.GetBar() { if ((Bar == null) && (innerFoo != null)) Bar = innerFoo.GetBar(); return Bar ?? 0; } int IFoo.GetBaz() { if ((Baz == null) && (innerFoo != null)) Baz = innerFoo.GetBaz(); return Baz ?? 0; } But it gets pretty repetitive if I'm doing this with 10 different properties and 30 different wrappers. So I figured, hey, let's make this generic: T LazyLoad<T>(ref T prop, Func<IFoo, T> loader) { if ((prop == null) && (innerFoo != null)) prop = loader(innerFoo); return prop; } Which almost gets me where I want, but not quite, because you can't ref an auto-property (or any property at all). In other words, I can't write this: int IFoo.GetBar() { return LazyLoad(ref Bar, f => f.GetBar()); // <--- Won't compile } Instead, I'd have to change Bar to have an explicit backing field and write explicit getters and setters. Which is fine, except for the fact that I end up writing even more redundant code than I was writing in the first place. Then I considered the possibility of using expression trees: T LazyLoad<T>(Expression<Func<T>> propExpr, Func<IFoo, T> loader) { var memberExpression = propExpr.Body as MemberExpression; if (memberExpression != null) { // Use Reflection to inspect/set the property } } This plays nice with refactoring - it'll work great if I do this: return LazyLoad(f => f.Bar, f => f.GetBar()); But it's not actually safe, because someone less clever (i.e. myself in 3 days from now when I inevitably forget how this is implemented internally) could decide to write this instead: return LazyLoad(f => 3, f => f.GetBar()); Which is either going to crash or result in unexpected/undefined behaviour, depending on how defensively I write the LazyLoad method. So I don't really like this approach either, because it leads to the possibility of runtime errors which would have been prevented in the first attempt. It also relies on Reflection, which feels a little dirty here, even though this code is admittedly not performance-sensitive. Now I could also decide to go all-out and use DynamicProxy to do method interception and not have to write any code, and in fact I already do this in some applications. But this code is residing in a core library which many other assemblies depend on, and it seems horribly wrong to be introducing this kind of complexity at such a low level. Separating the interceptor-based implementation from the IFoo interface by putting it into its own assembly doesn't really help; the fact is that this very class is still going to be used all over the place, must be used, so this isn't one of those problems that could be trivially solved with a little DI magic. The last option I've already thought of would be to have a method like: T LazyLoad<T>(Func<T> getter, Action<T> setter, Func<IFoo, T> loader) { ... } This option is very "meh" as well - it avoids Reflection but is still error-prone, and it doesn't really reduce the repetition that much. It's almost as bad as having to write explicit getters and setters for each property. Maybe I'm just being incredibly nit-picky, but this application is still in its early stages, and it's going to grow substantially over time, and I really want to keep the code squeaky-clean. Bottom line: I'm at an impasse, looking for other ideas. Question: Is there any way to clean up the lazy-loading code at the top, such that the implementation will: Guarantee compile-time safety, like the ref version; Actually reduce the amount of code repetition, like the Expression version; and Not take on any significant additional dependencies? In other words, is there a way to do this just using regular C# language features and possibly a few small helper classes? Or am I just going to have to accept that there's a trade-off here and strike one of the above requirements from the list?

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