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  • Jasmine testing coffeescript expect(setTimeout).toHaveBeenCalledWith

    - by Lee Quarella
    In the process of learning Jasmine, I've come to this issue. I want a basic function to run, then set a timeout to call itself again... simple stuff. class @LoopObj constructor: -> loop: (interval) -> #do some stuff setTimeout((=>@loop(interval)), interval) But I want to test to make sure the setTimeout was called with the proper args describe "loop", -> xit "does nifty things", -> it "loops at a given interval", -> my_nifty_loop = new LoopObj interval = 10 spyOn(window, "setTimeout") my_nifty_loop.loop(interval) expect(setTimeout).toHaveBeenCalledWith((-> my_nifty_loop.loop(interval)), interval) I get this error: Expected spy setTimeout to have been called with [ Function, 10 ] but was called with [ [ Function, 10 ] ] Is this because the (-> my_nifty_loop.loop(interval)) function does not equal the (=>@loop(interval)) function? Or does it have something to do with the extra square brackets around the second [ [ Function, 10 ] ]? Something else altogther? Where have I gone wrong?

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  • Sql server query using function and view is slower

    - by Lieven Cardoen
    I have a table with a xml column named Data: CREATE TABLE [dbo].[Users]( [UserId] [int] IDENTITY(1,1) NOT NULL, [FirstName] [nvarchar](max) NOT NULL, [LastName] [nvarchar](max) NOT NULL, [Email] [nvarchar](250) NOT NULL, [Password] [nvarchar](max) NULL, [UserName] [nvarchar](250) NOT NULL, [LanguageId] [int] NOT NULL, [Data] [xml] NULL, [IsDeleted] [bit] NOT NULL,... In the Data column there's this xml <data> <RRN>...</RRN> <DateOfBirth>...</DateOfBirth> <Gender>...</Gender> </data> Now, executing this query: SELECT UserId FROM Users WHERE data.value('(/data/RRN)[1]', 'nvarchar(max)') = @RRN after clearing the cache takes (if I execute it a couple of times after each other) 910, 739, 630, 635, ... ms. Now, a db specialist told me that adding a function, a view and changing the query would make it much more faster to search a user with a given RRN. But, instead, these are the results when I execute with the changes from the db specialist: 2584, 2342, 2322, 2383, ... This is the added function: CREATE FUNCTION dbo.fn_Users_RRN(@data xml) RETURNS varchar(100) WITH SCHEMABINDING AS BEGIN RETURN @data.value('(/data/RRN)[1]', 'varchar(max)'); END; The added view: CREATE VIEW vwi_Users WITH SCHEMABINDING AS SELECT UserId, dbo.fn_Users_RRN(Data) AS RRN from dbo.Users Indexes: CREATE UNIQUE CLUSTERED INDEX cx_vwi_Users ON vwi_Users(UserId) CREATE NONCLUSTERED INDEX cx_vwi_Users__RRN ON vwi_Users(RRN) And then the changed query: SELECT UserId FROM Users WHERE dbo.fn_Users_RRN(Data) = '59021626919-61861855-S_FA1E11' Why is the solution with a function and a view going slower?

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  • Returning object from function

    - by brainydexter
    I am really confused now on how and which method to use to return object from a function. I want some feedback on the solutions for the given requirements. Scenario A: The returned object is to be stored in a variable which need not be modified during its lifetime. Thus, const Foo SomeClass::GetFoo() { return Foo(); } invoked as: someMethod() { const Foo& l_Foo = someClassPInstance->GetFoo(); //... } Scneraio B: The returned object is to be stored in a variable which will be modified during its lifetime. Thus, void SomeClass::GetFoo(Foo& a_Foo_ref) { a_Foo_ref = Foo(); } invoked as: someMethod() { Foo l_Foo; someClassPInstance-GetFoo(l_Foo); //... } I have one question here: Lets say that Foo cannot have a default constructor. Then how would you deal with that in this situation, since we cant write this anymore: Foo l_Foo Scenario C: Foo SomeClass::GetFoo() { return Foo(); } invoked as: someMethod() { Foo l_Foo = someClassPInstance->GetFoo(); //... } I think this is not the recommended approach since it would incur constructing extra temporaries. What do you think ? Also, do you recommend a better way to handle this instead ?

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  • Windows Azure: Creating a subdirectories inside the blob

    - by veda
    I wanted to create some subdirectories inside my blob. But it is not working out well Here is my code protected void ButUpload_click(object sender, EventArgs e) { // store upladed file as a blob storage if (uplFileUpload.HasFile) { name = uplFileUpload.FileName; // get refernce to the cloud blob container CloudBlobContainer blobContainer = cloudBlobClient.GetContainerReference("documents"); if (textbox.Text != "") { name = textbox.Text + "/" + name; } // set the name for the uploading files string UploadDocName = name; // get the blob reference and set the metadata properties CloudBlockBlob blob = blobContainer.GetBlockBlobReference(UploadDocName); blob.Metadata["FILETYPE"] = "text"; blob.Properties.ContentType = uplFileUpload.PostedFile.ContentType; // upload the blob to the storage blob.UploadFromStream(uplFileUpload.FileContent); } } What I did is that, If I have to create a sub directory, I will enter the name of the sub directory in the textbox. for example, if I need to create a file named "test.txt" inside the sub directory "files" Then, my textbox.text = files and uplFileUpload.FileName = test.txt Now I will concatenate them and upload to the blob.. But it is not working well.. I am getting just https://test.core.windows.net/documents/files/ I am not getting the entire thing I was expecting https://test.core.windows.net/documents/files/test.txt What am I doing wrong... How to create sub directories inside the blob.

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  • Background color remaining when switching views

    - by Guy
    Hi Guys. I have a UIViewController named equationVC who's user interface is being programmatically created from another NSObject class called equationCon. Upon loading equationVC, a method called chooseInterface is called from the equationCon class. I have a global variable (globalVar) that points to a user defined string. chooseInterface finds a method in the equationCon class that matches the string globalVar points to. In this case, let's say that globalVar points to a string that is called "methodThatMatches." In methodThatMatches, another view controller needs to show the results of what methodThatMatches did. methodThatMatches creates a new equationVC that calls upon methodThatMatches2. As a test, each method changes the color of the background. When the application starts up, I get a purple background, but as soon as I hit backwards I get another purple screen, which should be yellow. I do not think that I am release the view properly. Can anyone help? -(void)chooseInterface { NSString* equationTemp = [globalVar stringByReplacingOccurrencesOfString:@" " withString:@""]; equationTemp = [equationTemp stringByReplacingOccurrencesOfString:@"'" withString:@""]; SEL equationName = NSSelectorFromString(equationTemp); NSLog(@"selector! %@",NSStringFromSelector(equationName)); if([self respondsToSelector:equationName]){ [self performSelector:equationName]; } } -(void)methodThatMatches{ self.equationVC.view.backgroundColor = [UIColor yellowColor]; [setGlobalVar:@"methodThatMatches2"]; EquationVC* temp = [[EquationVC alloc] init]; [[self.equationVC navigationController] pushViewController:temp animated:YES ]; [temp release]; } -(void)methodThatmatches2{ self.equationVC.view.backgroundColor = [UIColor purpleColor]; }

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  • LinqToSQL not updating database

    - by codegarten
    Hi. I created a database and dbml in visual studio 2010 using its wizards. Everything was working fine until i checked the tables data (also in visual studio server explorer) and none of my updates were there. using (var context = new CenasDataContext()) { context.Log = Console.Out; context.Cenas.InsertOnSubmit(new Cena() { id = 1}); context.SubmitChanges(); } This is the code i am using to update my database. At this point my database has one table with one field (PK) named ID. *INSERT INTO [dbo].Cenas VALUES (@p0) -- @p0: Input Int (Size = -1; Prec = 0; Scale = 0) [1] -- Context: SqlProvider(Sql2008) Model: AttributedMetaModel Build: 4.0.30319.1* This is LOG from the execution (printed the context log into the console). The problem i'm having is that these updates are not persistent in the database. I mean that when i query my database (visual studio server explorer - new query) i see the table is empty, every time. I am using a SQL Server database file (.mdf).

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  • Cannot connect to SQL Server from ASP.NET MVC app

    - by Dan Fergus
    I have an ASP.NET MVC app that has on a hosted server for over a year, connecting to SQL Server. I've had to change hosting services, the new one supports MVC 1.0. I've also moved a non MVC ASP app to the same hosting service. Now, MY MVC based app retturnes this error when I try to validate a user login. A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server) Now, the non-MVC app can access the exact same database and authenticate users just fine. The MVC app, when run from my dev box connects fine. It also run/connects/authenticates without problem when I install and run the site from an internal SQL 2008 server running IIS 7. I, along with the hosting support techs, am at a loss how the exact same connect string works every where except on the hosted server, and only when run from inside an ASP.NET MVC web app. Any ideas would be greatly appreciated.

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  • KeyStore, HttpClient, and HTTPS: Can someone explain this code to me?

    - by stormin986
    I'm trying to understand what's going on in this code. KeyStore trustStore = KeyStore.getInstance(KeyStore.getDefaultType()); FileInputStream instream = new FileInputStream(new File("my.keystore")); try { trustStore.load(instream, "nopassword".toCharArray()); } finally { instream.close(); } SSLSocketFactory socketFactory = new SSLSocketFactory(trustStore); Scheme sch = new Scheme("https", socketFactory, 443); httpclient.getConnectionManager().getSchemeRegistry().register(sch); My Questions: trustStore.load(instream, "nopassword".toCharArray()); is doing what exactly? From reading the documentation load() will load KeyStore data from an input stream (which is just an empty file we just created), using some arbitrary "nopassword". Why not just load it with null as the InputStream parameter and an empty string as the password field? And then what is happening when this empty KeyStore is being passed to the SSLSocketFactory constructor? What's the result of such an operation? Or -- is this simply an example where in a real application you would have to actually put a reference to an existing keystore file / password?

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  • There was no endpoint listening at net.pipe://localhost/...

    - by virsum
    I have two WCF services hosted in a single Windows Service on a Windows Server 2003 machine. If the Windows service needs to access either of the WCF services (like when a timed event occurs), it uses one of the five named pipe endpoints exposed (different service contracts). The service also exposes HTTP MetadataExchange endpoints for each of the two services, and net.tcp endpoints for consumers external to the server. Usually things work great, but every once in a while I get an error message that looks something like this: System.ServiceModel.EndpointNotFoundException: There was no endpoint listening at net.pipe://localhost/IPDailyProcessing that could accept the message. This is often caused by an incorrect address or SOAP action. See InnerException, if present, for more details. --- System.IO.PipeException: The pipe endpoint 'net.pipe://localhost/IPDailyProcessing' could not be found on your local machine. --- End of inner exception stack trace --- Server stack trace: at System.ServiceModel.Channels.PipeConnectionInitiator.GetPipeName(Uri uri) at System.ServiceModel.Channels.NamedPipeConnectionPoolRegistry.NamedPipeConnectionPool.GetPoolKey(EndpointAddress address, Uri via) at System.ServiceModel.Channels.ConnectionPoolHelper.EstablishConnection(TimeSpan timeout) at System.ServiceModel.Channels.ClientFramingDuplexSessionChannel.OnOpen(TimeSpan timeout) at System.ServiceModel.Channels.CommunicationObject.Open(TimeSpan timeout) at System.ServiceModel.Channels.ServiceChannel.OnOpen(TimeSpan timeout) at System.ServiceModel.Channels.CommunicationObject.Open(TimeSpan timeout) at System.ServiceModel.Channels.ServiceChannel.CallOpenOnce.System.ServiceModel.Channels.ServiceChannel.ICallOnce.Call(ServiceChannel channel, TimeSpan timeout) at System.ServiceModel.Channels.ServiceChannel.CallOnceManager.CallOnce(TimeSpan timeout, CallOnceManager cascade) at System.ServiceModel.Channels.ServiceChannel.EnsureOpened(TimeSpan timeout) at System.ServiceModel.Channels.ServiceChannel.Call(String action, Boolean oneway, ProxyOperationRuntime operation, Object[] ins, Object[] outs, TimeSpan timeout) at System.ServiceModel.Channels.ServiceChannel.Call(String action, Boolean oneway, ProxyOperationRuntime operation, Object[] ins, Object[] outs) at System.ServiceModel.Channels.ServiceChannelProxy.InvokeService(IMethodCallMessage methodCall, ProxyOperationRuntime operation) at System.ServiceModel.Channels.ServiceChannelProxy.Invoke(IMessage message) It doesn't happen reliably, which is maddening because I can't repeat it when I want to. In my windows service I also have some timed events and some file listeners, but these are fairly infrequent events. Does anyone have any ideas why I might be encountering an issue? Any help would be greatly appreciated.

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  • Html.ListBox() and MultiselectList

    - by Ivan90
    Hi guys, I've a little problem with an Html.ListBox! I am developing a personal blog in ASP.NET MVC 1.0 and I created an adminpanel where I can add and edit a post! During this two operations, I can add also tags! I think of use an Html.ListBox() helper to list all tags, and so I can select multiple tags to add in a post! The problem isn't during the add mode, but in the edit mode, where I have to pre-select post's tags! I read that I have to use a MultiSelectList and so in its constructor pass, tags' list and tag's list(pre-selected value). But I don't know how to use this class! I post, some code: This is my models method that get all list tags in selectlist public IEnumerable<SelectListItem> GetTagsListBox() { return from t in db.Tags orderby t.IDTag descending select new SelectListItem { Text = t.TagName, Value = t.IDTag.ToString(), }; } So in Edit (Get and Post), Add(Get and Post) I use a ViewData to pass this list in Html.ListBox(). ViewData["Tags"] = tagdb.GetTagsListBox(); And in my view <%=Html.ListBox("Tags",ViewData["Tags"] as SelectList) %> So with this code it's ok in Add Mode! But in Edit Mode I need to pre-select those values! So Now, of course I have to create a method that get all tagsbypostid! and then in ViewData what Must I to pass? Any suggest?

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  • Visual Studio crashes when I add a .settings file in a C++ Windows form application

    - by Ant
    I'm trying to add a .settings file in a windows form application by adding a (whatever) file in the project and have it named smthng.settings. Right after it is created, it crashes (if I look into the project's directory the file is there, but it's not "in" the project). Am I doing it wrong or could it be that the problem lies elsewhere? Edit: It seems that it's the settings designer that crashes. Partially Solved:If I add a (whatever).config file, then rename it to .settings and change it's file type to C/C++ Code (don't ask how I figured this out..) then I can add to it settings, but if I do add something that has any connection to the form then automatically a (whatever).config with thew same name spawns (which is identical to the (whatever).setting even if change one of them) and at the stdafx.cpp a #include '(whatever).h' appears, which is a problem, because there is not such a header. (if I erase it or just create a blank (whatever).h it doesn't work. Apparently I have to somehow connect all the data in the (w/e).settings to (w/e).h as well or maybe something else) Anyone had this problem before? Anyone has any ideas?

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  • Dynamic loading of shared objects using dlopen()

    - by Andy
    Hi, I'm working on a plain X11 app. By default, my app only requires libX11.so and the standard gcc C and math libs. My app has also support for extensions like Xfixes and Xrender and the ALSA sound system. But this feature shall be made optional, i.e. if Xfixes/Xrender/ALSA is installed on the host system, my app will offer extended functionality. If Xfixes or Xrender or ALSA is not there, my app will still run but some functionality will not be available. To achieve this behaviour, I'm not linking dynamically against -lXfixes, -lXrender and -lasound. Instead, I'm opening these libraries manually using dlopen(). By doing it this way, I can be sure that my app won't fail in case one of these optional components is not present. Now to my question: What library names should I use when calling dlopen()? I've seen that these differ from distro to distro. For example, on openSUSE 11, they're named the following: libXfixes.so libXrender.so libasound.so On Ubuntu, however, the names have a version number attached, like this: libXfixes.so.3 libXrender.so.1 libasound.so.2 So trying to open "libXfixes.so" would fail on Ubuntu, although the lib is obviously there. It just has a version number attached. So how should my app handle this? Should I let my app scan /usr/lib/ first manually to see which libs we have and then choose an appropriate one? Or does anyone have a better idea? Thanks guys, Andy

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  • How to get associated URLRequest from Event.COMPLETE fired by URLLoader

    - by matt lohkamp
    So let's say we want to load some XML - var xmlURL:String = 'content.xml'; var xmlURLRequest:URLRequest = new URLRequest(xmlURL); var xmlURLLoader:URLLoader = new URLLoader(xmlURLRequest); xmlURLLoader.addEventListener(Event.COMPLETE, function(e:Event):void{ trace('loaded',xmlURL); trace(XML(e.target.data)); }); If we need to know the source URL for that particular XML doc, we've got that variable to tell us, right? Now let's imagine that the xmlURL variable isn't around to help us - maybe we want to load 3 XML docs, named in sequence, and we want to use throwaway variables inside of a for-loop: for(var i:uint = 3; i > 0; i--){ var xmlURLLoader:URLLoader = new URLLoader(new URLRequest('content'+i+'.xml')); xmlURLLoader.addEventListener(Event.COMPLETE, function(e:Event):void{ trace(e.target.src); // I wish this worked... trace(XML(e.target.data)); }); } Suddenly it's not so easy, right? I hate that you can't just say e.target.src or whatever - is there a good way to associate URLLoaders with the URL they loaded data from? Am I missing something? It feels unintuitive to me.

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  • Java inheritance and super() isn't working as expected

    - by dwwilson66
    For a homework assignment, I'm working with the following. It's an assigned class structure, I know it's not the best design by a long shot. Class | Extends | Variables -------------------------------------------------------- Person | None | firstName, lastName, streetAddress, zipCode, phone CollegeEmployee | Person | ssn, salary,deptName Faculty | CollegeEmployee | tenure(boolean) Student | person | GPA,major So in the Faculty class... public class Faculty extends CollegeEmployee { protected String booleanFlag; protected boolean tenured; public Faculty(String firstName, String lastName, String streetAddress, String zipCode, String phoneNumber,String ssn, String department,double salary) { super(firstName,lastName,streetAddress,zipCode,phoneNumber, ssn,department,salary); String booleanFlag = JOptionPane.showInputDialog (null, "Tenured (Y/N)?"); if(booleanFlag.equals("Y")) tenured = true; else tenured = false; } } It was my understanding that super() in Faculty would allow access to the variables in CollegeEmployee as well as Person. With the code above, it compiles fine when I ONLY include the Person variables. As soon as I try to use ssn, department, or salary I get the following compile errors. Faculty.java:15: error: constructor CollegeEmployee in class CollegeEmployee can not be applied to the given types: super(firstName,lastName,streetAddress,zipCode,phoneNumber,ssn,department,salary); ^ Required: String,String,String,String,String Found: String,String,String,String,String,String,String,String reason: actual and formal argument lists differ in length I'm completely confused by this error...which is the actual and formal? Person has five arguments, CollegeEmployee has 3, so my guess is that something's funky with how the parameters are being passed...but I'm not quite sure where to begin fixing it. What am I missing?

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  • Multiple remote_form_for on the same page causes duplicate ids

    - by Ben Scheirman
    I've got a rails app that displays a list of items called modules. I'm iterating over these, rendering a partial for each one that includes a remote_form_for call. This all works, but fails HTML validation because my form text fields all have the same id. Is there a :prefix option on the form (or something else) I can use to get around this? Update: (some code) //_module_form.html.erb <% remote_form_for app_module do |f| %> <%= f.label :name %> <%= f.text_field :name %> <%= submit_tag 'Save' %> <%end %> //parent page <% @thing.modules.each do |app_module| %> <%= render :partial => "module_form", :locals => { :app_module => app_module } %> <% end %> So if I have more than 1 item in the collection, I render the identical form on the same page, and the form id and textbox id are duplicated. I can customize the form id pretty easily, but what about the text_box, since the controller is looking for specific named controls?

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  • 'C++ object destroyed' in QComboBox descendant editor in delegate

    - by Max
    Hi, all! I have modified combobox to hold colors, using QtColorCombo (http://qt.nokia.com/products/appdev/add-on-products/catalog/4/Widgets/qtcolorcombobox) as howto for the 'more...' button implementation details. It works fine in C++ and in PyQt on linux, but I get 'underlying C++ object was destroyed' when use this control in PyQt on Windows. It seels like the error happens when: ... # in constructor: self.activated.connect(self._emitActivatedColor) ... def _emitActivatedColor(self, index): if self._colorDialogEnabled and index == self.colorCount(): print '!!!!!!!!! QtGui.QColorDialog.getColor()' c = QtGui.QColorDialog.getColor() # <----- :( delegate fires 'closeEditor' print '!!!!!!!!! ' + c.name() if c.isValid(): self._numUserColors += 1 #at the next line currentColor() tries to access C++ layer and fails self.addColor(c, self.currentColor().name()) self.setCurrentIndex(index) ... Maybe console output will help. I've overridden event() in editor and got: ... MouseButtonRelease FocusOut Leave Paint Enter Leave FocusIn !!!!!!!!! QtGui.QColorDialog.getColor() WindowBlocked Paint WindowDeactivate !!!!!!!!! 'CloseEditor' fires! Hide HideToParent FocusOut DeferredDelete !!!!!!!!! #6e6eff ... Can someone explain, why there is such a different behaviour in the different environments, and maybe give a workaround to fix this. Here is minimal example: http://docs.google.com/Doc?docid=0Aa0otNVdbWrrZDdxYnF3NV80Y20yam1nZHM&hl=en

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  • What is the best way to return result from business layer to presentation layer when using linq - I

    - by samsur
    I have a business layer that has DTOs that are used in the presentation layer. This application uses entity framework. Here is an example of a class called RoleDTO public class RoleDTO { public Guid RoleId { get; set; } public string RoleName { get; set; } public string RoleDescription { get; set; } public int? OrganizationId { get; set; } } In the BLL I want to have a method that returns a list of DTO.. I would like to know which is the better approach: returning IQueryable or list of DTOs. Although i feel that returning Iqueryable is not a good idea because the connection needs to be open. Here are the 2 different methods using the different approaches public class RoleBLL { private servicedeskEntities sde; public RoleBLL() { sde = new servicedeskEntities(); } public IQueryable<RoleDTO> GetAllRoles() { IQueryable<RoleDTO> role = from r in sde.Roles select new RoleDTO() { RoleId = r.RoleID, RoleName = r.RoleName, RoleDescription = r.RoleDescription, OrganizationId = r.OrganizationId }; return role; } Note: in the above method the datacontext is a private attribute and set in the constructor, so that the connection stays opened. Second approach public static List GetAllRoles() { List roleDTO = new List(); using (servicedeskEntities sde = new servicedeskEntities()) { var roles = from pri in sde.Roles select new { pri.RoleID, pri.RoleName, pri.RoleDescription }; //Add the role entites to the DTO list and return. This is necessary as anonymous types can be returned acrosss methods foreach (var item in roles) { RoleDTO roleItem = new RoleDTO(); roleItem.RoleId = item.RoleID; roleItem.RoleDescription = item.RoleDescription; roleItem.RoleName = item.RoleName; roleDTO.Add(roleItem); } return roleDTO; } Please let me know, if there is a better approach - Thanks,

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  • MS Acess SQL - where clause to get year from date based on the year - data located in MS access form

    - by primus285
    OK, back again. I have a problem getting a drop down list to populate based on information in two fields. I have got the SQL correct as to Select just one year if I put DateValue('01/01/2001') in both places, but I am trying now to get it to grab the year data from the MS access form - another drop down named "cboYear". I'd hate to have to do something in VB, unless necessary. so far I have gotten this to pull up something (its always incorrect) SELECT DISTINCT Database_New.ASEC FROM Database_New WHERE Database_New.Date>=DateValue('01/01/' & [cboYear]) And Database_New.Date<=DateValue('12/31/' & [cboYear]); and SELECT DISTINCT Database_New.ASEC FROM Database_New WHERE Database_New.Date>=DateValue('01/01/' + [cboYear]) And Database_New.Date<=DateValue('12/31/' + [cboYear]); SELECT DISTINCT Database_New.ASEC FROM Database_New WHERE Database_New.Date>=DateValue('01/01/' AND [cboYear]) And Database_New.Date<=DateValue('12/31/' AND [cboYear]); both give errors saying that it is too complex to compute. Its probably something simple, but where do I go from here?

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  • How is a functional programming-based javascript app laid out?

    - by user321521
    I've been working with node.js for awhile on a chat app (I know, very original, but I figured it'd be a good learning project). Underscore.js provides a lot of functional programming concepts which look interesting, so I'd like to understand how a functional program in javascript would be setup. From my understanding of functional programming (which may be wrong), the whole idea is to avoid side effects, which are basically having a function which updates another variable outside of the function so something like var external; function foo() { external = 'bar'; } foo(); would be creating a side effect, correct? So as a general rule, you want to avoid disturbing variables in the global scope. Ok, so how does that work when you're dealing with objects and what not? For example, a lot of times, I'll have a constructor and an init method that initializes the object, like so: var Foo = function(initVars) { this.init(initVars); } Foo.prototype.init = function(initVars) { this.bar1 = initVars['bar1']; this.bar2 = initVars['bar2']; //.... } var myFoo = new Foo({'bar1': '1', 'bar2': '2'}); So my init method is intentionally causing side effects, but what would be a functional way to handle the same sort of situation? Also, if anyone could point me to either a python or javascript source code of a program that tries to be as functional as possible, that would also be much appreciated. I feel like I'm close to "getting it", but I'm just not quite there. Mainly I'm interested in how functional programming works with traditional OOP classes concept (or does away with it for something different if that's the case).

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  • Linux network stack : adding protocols with an LKM and dev_add_pack

    - by agent0range
    Hello, I have recently been trying to familiarize myself with the Linux Networking stack and device drivers (have both similarly named O'Reilly books) with the eventual goal of offloading UDP. I have already implemented UDP on the NIC but now the hard part... Rather than ask for assistance on this larger goal I was hoping someone could clarify for me a particular snippet I found that is part of a LKM which registeres a new protocol (OTP) that acts as a filter between the device driver and network stack. http://www.phrack.org/archives/55/p55_0x0c_Building%20Into%20The%20Linux%20Network%20Layer_by_lifeline%20&%20kossak.txt (Note: this Phrack article contains three different modules, code for the OTP is at the bottom of the page) In the init function of his example he has: otp_proto.type = htons(ETH_P_ALL); otp_proto.func = otp_func; dev_add_pack(&otp_proto); which (if I understand correctly) should register otp_proto as a packet sniffer and put it into the ptype_all data structure. My question is about the dev_add_pack. Is it the case that the protocol being registered as a filter will always be placed at this layer between L2 and the device driver? Or, for instance could I make such a filtering occur between the application and transport layers (analyze socket parameters) using the same process? I apologize if this is confusing - I am having some trouble wrapping my head around the bigger picture when it comes to modules altering kernel stack functionality. Thanks

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  • How to make a increasing numbers after filenames in C?

    - by zaplec
    Hi, I have a little problem. I need to do some little operations on quite many files in one little program. So far I have decided to operate them in a single loop where I just change the number after the name. The files are all named TFxx.txt where xx is increasing number from 1 to 80. So how can I open them all in a single loop one after one? I have tried this: for(i=0; i<=80; i++) { char name[8] = "TF"+i+".txt"; FILE = open(name, r); /* Do something */ } As you can see the second line would be working in python but not in C. I have tried to do similiar running numbering with C to this program, but I haven't found out yet how to do that. The format doesn't need to be as it is on the second line, but I'd like to have some advice of how can I solve this problem. All I need to do is just be able to open many files and do same operations to them.

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  • Textfield - what is wxTextCtrlNameStr?

    - by Wallter
    I'm trying to create a basic wxWidgets program with a text entry box, in the constructor there is a variable wxTextCtrlNameStr - in researching I can't seem to find wxTextCtrlNameStr? any help? wxTextCtrl(wxWindow* parent, wxWindowID id, const wxString& value = "", const wxPoint& pos = wxDefaultPosition, const wxSize& size = wxDefaultSize, long style = 0, const wxValidator& validator = wxDefaultValidator, const wxString& name = wxTextCtrlNameStr) My Code: MainFrame::MainFrame(const wxString& title) : wxFrame(NULL, wxID_ANY, title) { wxButton * Centigrade = new wxButton(this, BUTTON_CENTIGRADE, _T("to Centigrade"), wxPoint(20, 20), wxDefaultSize, 0); wxButton * Fahrenheit = new wxButton(this, BUTTON_FAHRENHEIT, _T("to Fahrenheit"), wxPoint(20, 40), wxDefaultSize, 0); F_txt = new wxTextCtrl(this, TXT_F_Main, "0", wxDefaultPosition, wxDefaultSize, wxDefaultValidator, wxTextCtrlNameStr); /***********************************************/ C_txt = new wxTextCtrl(this, TXT_C_Main, "0", wxDefaultPosition, wxDefaultSize, wxDefaultValidator, wxTextCtrlNameStr); /***********************************************/ ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ...

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  • Access modifiers - Property on business objects - getting and setting

    - by Mike
    Hi, I am using LINQ to SQL for the DataAccess layer. I have similar business objects to what is in the data access layer. I have got the dataprovider getting the message #23. On instantiation of the message, in the message constructor, it gets the MessageType and makes a new instance of MessageType class and fills in the MessageType information from the database. Therefore; I want this to get the Name of the MessageType of the Message. user.Messages[23].MessageType.Name I also want an administrator to set the MessageType user.Messages[23].MessageType = MessageTypes.LoadType(3); but I don't want the user to publicly set the MessageType.Name. But when I make a new MessageType instance, the access modifier for the Name property is public because I want to set that from an external class (my data access layer). I could change this to property to internal, so that my class can access it like a public variable, and not allow my other application access to modify it. This still doesn't feel right as it seems like a public property. Are public access modifiers in this situation bad? Any tips or suggestions would be appreciated. Thanks.

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  • Mutual class instances in C++

    - by SepiDev
    Hi guys. What is the issue with this code? Here we have two files: classA.h and classB.h classA.h: #ifndef _class_a_h_ #define _class_a_h_ #include "classB.h" class B; //???? class A { public: A() { ptr_b = new B(); //???? } virtual ~A() { if(ptr_b) delete ptr_b; //???? num_a = 0; } int num_a; B* ptr_b; //???? }; #endif //_class_a_h_ classB.h: #ifndef _class_b_h_ #define _class_b_h_ #include "classA.h" class A; //???? class B { public: B() { ptr_a = new A(); //???? num_b = 0; } virtual ~B() { if(ptr_a) delete ptr_a; //???? } int num_b; A* ptr_a; //???? }; #endif //_class_b_h_ when I try to compile it, the compiler (g++) says: classB.h: In constructor ‘B::B()’: classB.h:12: error: invalid use of incomplete type ‘struct A’ classB.h:6: error: forward declaration of ‘struct A’ classB.h: In destructor ‘virtual B::~B()’: classB.h:16: warning: possible problem detected in invocation of delete operator: classB.h:16: warning: invalid use of incomplete type ‘struct A’ classB.h:6: warning: forward declaration of ‘struct A’ classB.h:16: note: neither the destructor nor the class-specific operator delete will be called, even if they are declared when the class is defined.

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  • Remotely connecting two non-local computers with sockets

    - by Velizar Hristov
    This question seems like something very obvious to ask, and yet I spent more than an hour trying to find an answer. First I host and wait for someone to connect. Then, from another instance of the application, I try to connect with a socket - for the constructor, I use InetAddress, port. The port is always right, and everything works if I use "localhost" for the address. However, if I type my IP, I get an IOException. I even sent the application to someone else, gave him my IP, and it didn't work. The aim of the application is to connect two computers. It's in Java. Here is the relevant code. Server: ServerSocket serverSocket = new ServerSocket(port); Socket clientSocket = serverSocket.accept(); Client: InetAddress a = InetAddress.getByName(ip); Socket s = new Socket(a, port); I don't get past that. Obviously, the values of int port and String ip are taken from text fields. Edit: the purpose of my application is to connect two non-local computers.

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