Search Results

Search found 7375 results on 295 pages for 'parameter'.

Page 246/295 | < Previous Page | 242 243 244 245 246 247 248 249 250 251 252 253  | Next Page >

  • derived class as default argument g++

    - by Vincent
    Please take a look at this code: template<class T> class A { class base { }; class derived : public A<T>::base { }; public: int f(typename A<T>::base& arg = typename A<T>::derived()) { return 0; } }; int main() { A<int> a; a.f(); return 0; } Compiling generates the following error message in g++: test.cpp: In function 'int main()': test.cpp:25: error: default argument for parameter of type 'A<int>::base&' has type 'A<int>::derived' The basic idea (using derived class as default value for base-reference-type argument) works in visual studio, but not in g++. I have to publish my code to the university server where they compile it with gcc. What can I do? Is there something I am missing?

    Read the article

  • How To Share Information Between Django and Javascript?

    - by Randy
    So I am pretty new to both Django and Javascript (I am using JQuery) and I am wondering if I am doing a hack or if there are more slick ways to send client-side displayed database ids to the django server-side. Here is my process: I have a dataTable (http://datatables.net) that I am displaying rows of data by using the bProcessing option to use AJAX to retrieve records from the database. The URL in my urls.py is something like: url(r'^assets/activitylog/(?P<cid>.*)$', views.getActivityTable_ajax, name="activitylog_table"), and my dataTable ajax-relavant code is something like: "sAjaxSource": "/assets/activitylog/" + getIDFromHTML(), where the javascript function getIDFromHTML() grabs <cid> that is used by the Django view is simply: function getIDFromHTML(){ // Simply return the text in the #release_id div element from the HTML return $("#release_id").html(); }; This is the part that seems "hacky" to me. I am inserting into my template code the database id that I am using in the datatables URL (with display:none in the css) just so I can pass it back to the view. Most of this is necessitated because one cannot use django template tags in the javascript code unless the code is embedded into the HTML itself, which I am not (and will not) do. The only other thing that I have found is to change the URL to get rid of the parameter passed in to: url(r'^assets/activitylog', views.getActivityTable_ajax, name="activitylog_table"), and change the view code to: def getActivityTable_ajax(request): """Returns the activity for a given pid from HTTP GET ajax reqest""" pid = int(urlparse.urlparse(request.META['HTTP_REFERER']).path.split('/')[-1]) # rest of view code here... since the id that I need is on the end of this referer url. This way I don't have to monkey around with embedding the hidden database id into the HTML and passing it back to via ajax the the table population view code. Is it okay to use HTTP_REFERER in the request object in this manner? Am I going about this in the totally wrong way? Thanks in advance!

    Read the article

  • Which design is better (OO Design)?

    - by Tattat
    I have an "Enemy" object, that have many "gun" . Each "gun" can fire "bullet". Storing "gun" is using an array. when the "gun" is fired, the "bullet" will be created. And the enemy object will have an array to store the "bullet". So, I am thinking about the fire method. I am think making a firebulletFromGun in the "enemy". It need have a parameter: "gun". while this method is called. The "enemy" 's bullet will be added in the Array. Another design is writing the fire method in the "gun". The "enemy" use the "gun"'s fire method. And the "gun" will return a "bullet" object, and it will be added in the Array of "enemy". Both method can work, but which way is better? or they are similar the same? plx drop ur ideas/suggestions. thz.

    Read the article

  • How does C#'s DateTime.Now affect query plan caching in SQL Server?

    - by Bill Paetzke
    Given: Let's say we have a stored procedure. It reports data back to a user on a webpage. The user can set a date range. If the user sets today's date as the "end date," which includes today's data, the web app passes DateTime.Now to the sql proc. Let's say that one user runs a report--5/1/2010 to now--over and over several times. On the webpage, the user sees "5/1/2010" to "5/4/2010." But the web app passes DateTime.Now to the sql proc as the end date. So, the end date in the proc will always be different, although the user is querying a similar date range. Assume the number of records in the table and number of users are large. So any performance gains matter. Hence the importance of the question. Question: Does passing DateTime.Now as a parameter to a proc prevent SQL Server from caching the query plan? If so, then is the web app missing out on huge performance gains? Possible Solution: I thought DateTime.Today.AddDays(1) would be a possible solution. It would allow the user to get the latest data and always pass the same end date to the sql proc--"5/5/2010" in this case. Please speak to this as well. Sample proc and execution (if that helps to understand): CREATE PROCEDURE GetFooData @StartDate datetime @EndDate datetime AS SELECT * FROM Foo WHERE LogDate >= @StartDate AND LogDate < @EndDate Here's a sample execution using DateTime.Now: EXEC GetFooData '2010-05-01', '2010-05-04 15:41:27' -- passed in DateTime.Now Here's a sample execution using DateTime.Today.AddDays(1) EXEC GetFooData '2010-05-01', '2010-05-05' -- passed in DateTime.Today.AddDays(1) The same data is returned for both procs, since the current time is: 2010-05-04 15:41:27.

    Read the article

  • c++ callback syntax in a class

    - by Mr Bell
    I am trying to figure out the syntax to register a callback with this 3rd party software. I think it is probably a basic question, I just am not too familiar with c++. They have a method for registering a callback function so their code can call a function in my code when an event happens. They provided a working example that registers the callback from the main file, but I want to know how to do it when working inside a class Their method signature: smHTRegisterHeadPoseCallback(smEngineHandle engine_handle, void *user_data, smHTHeadPoseCallback callback_fun); Working example from the main file: void STDCALL receiveHeadPose(void *,smEngineHeadPoseData head_pose, smCameraVideoFrame video_frame) { ... } void main() { ... smHTRegisterHeadPoseCallback(engine_handle,0,receiveHeadPose) ... } But I want to use this from my class MyClass.h class FaceEngine { public: void STDCALL receiveFaceData(void *, smEngineFaceData face_data, smCameraVideoFrame video_frame); ... MyClass.cpp void FaceEngine::Start(void) { rc = smHTRegisterFaceDataCallback(hFaceAPIEngine,0,&FaceEngine::receiveFaceData); ... Results in this compiler error: Error 1 error C2664: 'smHTRegisterFaceDataCallback' : cannot convert parameter 3 from 'void (__stdcall FaceEngine::* )(void *,smEngineFaceData,smCameraVideoFrame)' to 'smHTFaceDataCallback' d:\stuff\programming\visual studio 2008\projects\tut02_vertices\faceengine.cpp 43 Beard If my question isn't clear please let me know how I can clarify.

    Read the article

  • Show values in TDropDownList in PRADO.

    - by Muhammad Sajid
    I m new to PRADO, I have a file Home.page with code: <%@ Title="Contact List" %> <h1>Contact List</h1> <a href="<%= $this->Service->constructUrl('insert')%>">Create New Contact</a> <br/> <com:TForm> <com:TDropDownList ID="personInfo"> <com:TListItem Value="value 1" Text="item 1" /> <com:TListItem Value="value 2" Text="item 2" Selected="true" /> <com:TListItem Value="value 3" Text="item 3" /> <com:TListItem Value="value 4" Text="item 4" /> </com:TDropDownList> </com:TForm> & Home.php with code <?php class Home extends TPage { /** * Populates the datagrid with user lists. * This method is invoked by the framework when initializing the page * @param mixed event parameter */ public function onInit($param) { parent::onInit($param); // fetches all data account information $rec = ContactRecord::finder()->findAll(); } } ?> the $rec contain array of all values. Now I want to show all name in Dropdown list. I tried my best but fail. Can anyone help me? Thanks

    Read the article

  • Strange Sql Server 2005 behavior

    - by Justin C
    Background: I have a site built in ASP.NET with Sql Server 2005 as it's database. The site is the only site on a Windows Server 2003 box sitting in my clients server room. The client is a local school district, so for data security reasons there is no remote desktop access and no remote Sql Server connection, so if I have to service the database I have to be at the terminal. I do have FTP access to update ASP code. Problem: I was contacted yesterday about an issue with the system. When I looked in to it, it seems a bug that I had solved nearly a year ago had returned. I have a stored procedure that used to take an int as a parameter but a year ago we changed the structure of the system and updated the stored procedure to take an nvarchar(10). The stored procedure somehow changed back to taking an int instead of an nvarchar. There is an external hard drive connected to the server that copies data periodically and has the ability to restore the server in case of failure. I would have assumed that somehow an older version of the database had been restored, but data that I know was inserted 7 days and 1 day before the bug occurred is still in the database. Question: Is there anyway that the structure of a Sql Server 2005 database can revert to a previous version or be restored to a previous version without touching the actual data? No one else should have access to the server so I'm going a little insane trying to figure out how this even happened. Any ideas?

    Read the article

  • How to submit Nothing as a route value to ASP MVC

    - by Adam
    I have a route with several optional parameters. These are possible search terms in different fields. So, for example, if I have fields key, itemtype and text then I have in global.asax: routes.MapRoute( _ "Search", _ "Admin.aspx/Search/{Key}/{ItemType}/{Text}", _ New With {.controller = "Admin", .action = "Search" .Key = Nothing, .ItemType = Nothing, .Text = Nothing} _ ) My action takes optional parameters: Function Search(Optional ByVal Key As String = Nothing, _ Optional ByVal ItemType As Integer = 0, _ Optional ByVal Text As String = Nothing, _ Optional ByVal OtherText As String = Nothing) It then checks if the Key and Text strings have a non-null (and non-empty) value and adds search terms to the db request as needed. However, is it possible to send in a null value for, for example, Key but still send in a value for Text? If so, what does the URL look like? (Admin.aspx/Search//0/Foo doesn't work :) ) I know I can handle this using a parameter array instead, but wondered if this was possible using the sort of route described? I could of course define some other value as equivalent to null (for example, a space/%20) but is there any way to send a null value in the URL? I'm suspecting not, but thought I'd see if anyone knew of one. I'm using ASP MVC 2 for this project.

    Read the article

  • Which pdf elements could cause crashes?

    - by Felixyz
    This is a very general question but it's based on a specific problem. I've created a pdf reader app for the iPad and it works fine except for certain pdf pages which always crash the app. We now found out that the very same pages cause Safari to crash as well, so as I had started to suspect the problem is somewhere in Apple's pdf rendering code. From what I have been able to see, the crashing pages cause the rendering libraries to start allocating memory like mad until the app is killed. I have nothing else to help me pinpoint what triggers this process. It doesn't necessarily happen with the largest documents, or the ones with the most shapes. In fact, we haven't found any parameter that helps us predict which pages will crash and which not. Now we just discovered that running the pages through a consumer program that lets you merge docs gets rid of the problem, but I haven't been able to detect which attribute or element it is that is the key. Changing documents by hand is also not an option for us in the long run. We need to run an automated process on our server. I'm hoping someone with deeper knowledge about the pdf file format would be able to point me in a reasonable direction to look for document features that could cause this kind of behavior. All I've found so far is something about JBIG2 images, and I don't think we have any of those.

    Read the article

  • Is there a pattern for initializing objects created wth a DI container

    - by Igor Zevaka
    I am trying to get Unity to manage the creation of my objects and I want to have some initialization parameters that are not known until run-time: At the moment the only way I could think of the way to do it is to have an Init method on the interface. interface IMyIntf { void Initialize(string runTimeParam); string RunTimeParam { get; } } Then to use it (in Unity) I would do this: var IMyIntf = unityContainer.Resolve<IMyIntf>(); IMyIntf.Initialize("somevalue"); In this scenario runTimeParam param is determined at run-time based on user input. The trivial case here simply returns the value of runTimeParam but in reality the parameter will be something like file name and initialize method will do something with the file. This creates a number of issues, namely that the Initialize method is available on the interface and can be called multiple times. Setting a flag in the implementation and throwing exception on repeated call to Initialize seems way clunky. At the point where I resolve my interface I don't want to know anything about the implementation of IMyIntf. What I do want, though, is the knowledge that this interface needs certain one time initialization parameters. Is there a way to somehow annotate(attributes?) the interface with this information and pass those to framework when the object is created? Edit: Described the interface a bit more.

    Read the article

  • VS2010 Web Deploy: how to remove absolute paths and automate setAcl?

    - by Julien Lebosquain
    The integrated Web Deployment in Visual Studio 2010 is pretty nice. It can create a package ready to be deployed using MSDeploy on a target IIS machine. Problem is, this package will be redistributed to a client that will install it himself using the "Import Application" from IIS when MSDeploy is installed. The default package created always include the full path from the development machine, "D:\Dev\XXX\obj\Debug\Package\PackageTmp" in the source manifest file. It doesn't prevent installation of course since it was designed this way, but it looks ugly in the import dialog and has no meaning to the client. Worse he will wonder what are those paths and it looks quite confusing. By customizing the .csproj file (by adding MSBuild properties used by the package creation task), I managed to add additional parameters to the package. However, I spent most of the afternoon in the 2600 lines long Web.Publishing.targets trying to understand what parameter influenced the "development path" behavior, in vain. I also tried to use the setAcl to customize security on a given folder after deployment, but I only managed to do this with MSBuild by using a relative path... it shouldn't matter if I resolve the first problem though. I could modify the generated archive after its creation but I would prefer if everything was automatized using MSBuild. Does anyone know how to do that?

    Read the article

  • How can i use a commandlinetool (ie. sox) via subprocess.Popen with mod_wsgi?

    - by marue
    I have a custom django filefield that makes use of sox, a commandline audiotool. This works pretty well as long as i use the django development server. But as soon as i switch to the production server, using apache2 and mod_wsgi, mod_wsgi catches every output to stdout. This makes it impossible to use the commandline tool to evaluate the file, for example use it to check if the uploaded file really is an audio file like this: filetype=subprocess.Popen([sox,'--i','-t','%s'%self.path], shell=False,\ stdout=subprocess.PIPE, stderr=subprocess.PIPE) (filetype,error)=filetype.communicate() if error: raise EnvironmentError((1,'AudioFile error while determining audioformat: %s'%error)) Is there a way to workaround for this? edit the error i get is "missing filename". I am using mod_wsgi 2.5, standard with ubuntu 8.04. edit2 What exactly happens, when i call subprocess.Popen from within django in mod_wsgi? Shouldn't subprocess stdin/stdout be independent from django stdin/stdout? In that case mod_wsgi should not affect programms called via subprocess... I'm really confused right now, because the file i am trying to access is a temporary file, created via a filenamevariable that i pass to the file creation and the subprocess command. That file is being written to /tmp, where the rights are 777, so it can't be a rights issue. And the error message is not "file does not exist", but "missing filename", which suggests i am not passing a filename as parameter to the commandlinetool.

    Read the article

  • C++: is it safe to work with std::vectors as if they were arrays?

    - by peoro
    I need to have a fixed-size array of elements and to call on them functions that require to know about how they're placed in memory, in particular: functions like glVertexPointer, that needs to know where the vertices are, how distant they are one from the other and so on. In my case vertices would be members of the elements to store. to get the index of an element within this array, I'd prefer to avoid having an index field within my elements, but would rather play with pointers arithmetic (ie: index of Element *x will be x - & array[0]) -- btw, this sounds dirty to me: is it good practice or should I do something else? Is it safe to use std::vector for this? Something makes me think that an std::array would be more appropriate but: Constructor and destructor for my structure will be rarely called: I don't mind about such overhead. I'm going to set the std::vector capacity to size I need (the size that would use for an std::array, thus won't take any overhead due to sporadic reallocation. I don't mind a little space overhead for std::vector's internal structure. I could use the ability to resize the vector (or better: to have a size chosen during setup), and I think there's no way to do this with std::array, since its size is a template parameter (that's too bad: I could do that even with an old C-like array, just dynamically allocating it on the heap). If std::vector is fine for my purpose I'd like to know into details if it will have some runtime overhead with respect to std::array (or to a plain C array): I know that it'll call the default constructor for any element once I increase its size (but I guess this won't cost anything if my data has got an empty default constructor?), same for destructor. Anything else?

    Read the article

  • How to specialize a type parameterized argument to multiple different types for in Scala?

    - by jmount
    I need a back-check (please). In an article ( http://www.win-vector.com/blog/2010/06/automatic-differentiation-with-scala/ ) I just wrote I stated that it is my belief in Scala that you can not specify a function that takes an argument that is itself a function with an unbound type parameter. What I mean is you can write: def g(f:Array[Double]=>Double,Array[Double]):Double but you can not write something like: def g(f[Y]:Array[Y]=>Double,Array[Double]):Double because Y is not known. The intended use is that inside g() I will specialize fY to multiple different types at different times. You can write: def g[Y](f:Array[Y]=>Double,Array[Double]):Double but then f() is of a single type per call to g() (which is exactly what we do not want). However, you can get all of the equivalent functionality by using a trait extension instead insisting on passing around a function. What I advocated in my article was: 1) Creating a trait that imitates the structure of Scala's Function1 trait. Something like: abstract trait VectorFN { def apply[Y](x:Array[Y]):Y } 2) declaring def g(f:VectorFN,Double):Double (using the trait is the type). This works (people here on StackOverflow helped me find it, and I am happy with it)- but am I mis-representing Scala by missing an even better solution?

    Read the article

  • C# - Advantages/Disadvantages of different implementations for Comparing Objects

    - by Kevin Crowell
    This questions involves 2 different implementations of essentially the same code. First, using delegate to create a Comparison method that can be used as a parameter when sorting a collection of objects: class Foo { public static Comparison<Foo> BarComparison = delegate(Foo foo1, Foo foo2) { return foo1.Bar.CompareTo(foo2.Bar); }; } I use the above when I want to have a way of sorting a collection of Foo objects in a different way than my CompareTo function offers. For example: List<Foo> fooList = new List<Foo>(); fooList.Sort(BarComparison); Second, using IComparer: public class BarComparer : IComparer<Foo> { public int Compare(Foo foo1, Foo foo2) { return foo1.Bar.CompareTo(foo2.Bar); } } I use the above when I want to do a binary search for a Foo object in a collection of Foo objects. For example: BarComparer comparer = new BarComparer(); List<Foo> fooList = new List<Foo>(); Foo foo = new Foo(); int index = fooList.BinarySearch(foo, comparer); My questions are: What are the advantages and disadvantages of each of these implementations? What are some more ways to take advantage of each of these implementations? Is there a way to combine these implementations in such a way that I do not need to duplicate the code? Can I achieve both a binary search and an alternative collection sort using only 1 of these methods?

    Read the article

  • doubt in javascript name validation

    - by raja
    Hi: I am using the below validation for textbox which accepts only alphabets and maximum of 50 characters. I am passing the object directly in the parameter. The below case by giving the field name i.e "my_text" directly is working is working fine. But if i pass it in variable, that time it is not working(commented the if statement). Please help me. My requirement is each time when we enter the charater, the hardcode field name should not be used in the validation. <html><head> <script language=JavaScript> function check_length(my_form,fieldName) { alert(fieldName); // if (my_form.fieldName.value.length >= maxLen) { if (my_form.my_text.value.length >= maxLen) { var msg = "You have reached your maximum limit of characters allowed"; alert(msg); my_form.my_text.value = my_form.my_text.value.substring(0, maxLen); } else{ var keyCode = window.event.keyCode; if ((keyCode < 65 || keyCode > 90) && (keyCode < 97 || keyCode > 123) && keyCode != 32) { window.event.returnValue = false; alert("Enter only Alphabets"); } my_form.text_num.value = maxLen - my_form.my_text.value.length;} } </script> </head> <body> <form name=my_form method=post> <input type="text" onKeyPress=check_length(this.form,this.name); name=my_text rows=4 cols=30> <br> <input size=1 value=50 name=text_num> Characters Left </form> </body> </html>

    Read the article

  • What OOP pattern to use when only adding new methods, not data?

    - by Jonathon Reinhart
    Hello eveyone... In my app, I have deal with several different "parameters", which derive from IParameter interface, and also ParamBase abstract base class. I currently have two different parameter types, call them FooParameter and BarParameter, which both derive from ParamBase. Obviously, I can treat them both as IParameters when I need to deal with them generically, or detect their specific type when I need to handle their specific functionality. My question lies in specific FooParameters. I currently have a few specific ones with their own classes which derive from FooParameter, we'll call them FP12, FP13, FP14, etc. These all have certain characteristics, which make me treat them differently in the UI. (Most have names associated with the individual bits, or ranges of bits). Note that these specific, derived FP's have no additional data associated with them, only properties (which refer to the same data in different ways) or methods. Now, I'd like to keep all of these parameters in a Dictionary<String, IParameter> for easy generic access. The problem is, if I want to refer to a specific one with the special GUI functions, I can't write: FP12 fp12 = (FP12)paramList["FP12"] because you can't downcast to a derived type (rightfully so). But in my case, I didn't add any data, so the cast would theoretically work. What type of programming model should I be using instead? Thanks!

    Read the article

  • Convert a raw string to an array of big-endian words with Ruby

    - by Zag zag..
    Hello, I would like to convert a raw string to an array of big-endian words. As example, here is a JavaScript function that do it well (by Paul Johnston): /* * Convert a raw string to an array of big-endian words * Characters >255 have their high-byte silently ignored. */ function rstr2binb(input) { var output = Array(input.length >> 2); for(var i = 0; i < output.length; i++) output[i] = 0; for(var i = 0; i < input.length * 8; i += 8) output[i>>5] |= (input.charCodeAt(i / 8) & 0xFF) << (24 - i % 32); return output; } I believe the Ruby equivalent can be String#unpack(format). However, I don't know what should be the correct format parameter. Thank you for any help. Regards

    Read the article

  • select option clears when page loads in php

    - by user79685
    Hey guys, the scenario is this: see select below <form name="limit"> <select name="limiter" onChange="limit(this.value)"> <option selected="selected">&nbsp;</option> <option value="5">5</option> <option value="10">10</option> <option value="15">15</option> </select> </form> I want whenever any option is selected for 3 things to happen: 1.) js limit() function is called which all it does its takes current url, adds new query parameter 'limit' with the user selected value eg: http://localhost/blahblah/apps/category.php?pg=1&catId=3021&limit=5 (this will cause the category.php page to be hit and # of product displayed limited to the value selected by user) 2.)Once the url is hit, it reloads but i DONT want the value selected to reset back to the default (which it currently does). I want it to reflect the users selection after page reload. 3.) Also, when i move to the next page (pagination), i would like the state to be carried ova to the next page (ie. remembering the user selection).

    Read the article

  • c# syntax and Linq, IQueryable

    - by hdiver
    Hello. This is a question about the SYNTAX of c# and NOT about how we call/use IQueryable Can someone please explain to me: We have this declaration (System.Linq): public static double Average<TSource>(this IQueryable<TSource> source, Expression<Func<TSource, int>> selector) and to call the Average double average = fruits.AsQueryable().Average(s => s.Length); I understand how to call the Average and all the similar static method of IQueryable but I don’t understand the syntax of the declaration. public static double Average<TSource>(this IQueryable<TSource> source, Expression<Func<TSource, int>> selector) What does the <TSource> mean in Average<TSource>( and also the this IQueryable<TSource> source. since only one parameter passes when we call it and the actual lamda expression (s => s.Length); Thanks in advance.

    Read the article

  • Threadsafe way of exposing keySet()

    - by Jake
    This must be a fairly common occurrence where I have a map and wish to thread-safely expose its key set: public MyClass { Map<String,String> map = // ... public final Set<String> keys() { // returns key set } } Now, if my "map" is not thread-safe, this is not safe: public final Set<String> keys() { return map.keySet(); } And neither is: public final Set<String> keys() { return Collections.unmodifiableSet(map.keySet()); } So I need to create a copy, such as: public final Set<String> keys() { return new HashSet(map.keySet()); } However, this doesn't seem safe either because that constructor traverses the elements of the parameter and add()s them. So while this copying is going on, a ConcurrentModificationException can happen. So then: public final Set<String> keys() { synchronized(map) { return new HashSet(map.keySet()); } } seems like the solution. Does this look right?

    Read the article

  • Rails 3 : Can't get form_for to work as a 'delete' following the RESTful achitecture => always giving a ROUTING ERROR

    - by Alex
    I have a very simple render that goes as follow: <%= form_for(:relationships, :url => relationships_path, :html => {:method => 'delete'}) do |f| %> <div><%= f.hidden_field :user_id_to_unfollow, :value => @user.id %></div> <div class="actions"><%= f.submit "Unfollow" %></div> <% end %> When I submit this form it will always give me a Routing Error No route matches "/relationships" on my page. In my relationships controller, I have created all the propers methods: def create ... end def destroy ... end def update ... end def show ... end And in my routes config I have made sure to allow all routes for the relationships controller resources :relationships But I can't seem to get into the destroy method of the controller :( However if I remove the :html => {:method => 'delete'} method parameter in the form_for then I get to the create method of the controller no pb. I don't get it.... Alex

    Read the article

  • Binding not working correctly in silverlight

    - by Harsh Maurya
    I am using a DataGrid in my silverlight project which contains a custom checkbox column. I have binded its command property with a property of my ViewModel class. Now, the problem is that I want to send the "selected item" of DataGrid through the command paramter for which I have written the following code : <sdk:DataGrid AutoGenerateColumns="False" Margin="10,0,10,0" Name="dataGridOrders" ItemsSource="{Binding OrderList}" Height="190"> <sdk:DataGrid.Columns> <sdk:DataGridTemplateColumn Header="Select"> <sdk:DataGridTemplateColumn.CellTemplate> <DataTemplate> <CheckBox> <is:Interaction.Triggers> <is:EventTrigger EventName="Checked"> <is:InvokeCommandAction Command="{Binding Source={StaticResource ExecutionTraderHomePageVM},Path=OrderSelectedCommand,Mode=TwoWay}" CommandParameter="{Binding ElementName=dataGridOrders,Path=SelectedItem}" /> </is:EventTrigger> <is:EventTrigger EventName="Unchecked"> <is:InvokeCommandAction Command="{Binding Source={StaticResource ExecutionTraderHomePageVM},Path=OrderSelectedCommand,Mode=TwoWay}" CommandParameter="{Binding ElementName=dataGridOrders,Path=SelectedItem}" /> </is:EventTrigger> </is:Interaction.Triggers> </CheckBox> But I am always getting null in the parameter of my command's execute method. I have tried with other properties of DataGrid such as Width, ActualHeight e.t.c. but of no use. What am I missing here ?

    Read the article

  • Pass Linq Expression to a function

    - by Kushan Hasithe Fernando
    I want to pass a property list of a class to a function. with in the function based on property list I'm going to generate a query. As exactly same functionality in Linq Select method. Here I'm gonna implement this for Ingress Database. As an example, in front end I wanna run a select as this, My Entity Class is like this public class Customer { [System.Data.Linq.Mapping.ColumnAttribute(Name="Id",IsPrimaryKey=true)] public string Id { get; set; } [System.Data.Linq.Mapping.ColumnAttribute(Name = "Name")] public string Name { get; set; } [System.Data.Linq.Mapping.ColumnAttribute(Name = "Address")] public string Address { get; set; } [System.Data.Linq.Mapping.ColumnAttribute(Name = "Email")] public string Email { get; set; } [System.Data.Linq.Mapping.ColumnAttribute(Name = "Mobile")] public string Mobile { get; set; } } I wanna call a Select function like this, var result = dataAccessService.Select<Customer>(C=>C.Name,C.Address); then,using result I can get the Name and Address properties' values. I think my Select function should looks like this, ( *I think this should done using Linq Expression. But im not sure what are the input parameter and return type. * ) Class DataAccessService { // I'm not sure about this return type and input types, generic types. public TResult Select<TSource,TResult>(Expression<Func<TSource,TResult>> selector) { // Here using the property list, // I can get the ColumnAttribute name value and I can generate a select query. } } This is a attempt to create a functionality like in Linq. But im not an expert in Linq Expressions. There is a project call DbLinq from MIT, but its a big project and still i couldn't grab anything helpful from that. Can someone please help me to start this, or can someone link me some useful resources to read about this.

    Read the article

  • How do I use .htaccess to redirect to a URL containing HTTP_HOST?

    - by Jon Cram
    Problem I need to redirect some short convenience URLs to longer actual URLs. The site in question uses a set of subdomains to identify a set of development or live versions. I would like the URL to which certain requests are redirected to include the HTTP_HOST such that I don't have to create a custom .htaccess file for each host. Host-specific Example (snipped from .htaccess file) Redirect /terms http://support.dev01.example.com/articles/terms/ This example works fine for the development version running at dev01.example.com. If I use the same line in the main .htaccess file for the development version running under dev02.example.com I'd end up being redirected to the wrong place. Ideal rule (not sure of the correct syntax) Redirect /terms http://support.{HTTP_HOST}/articles/terms/ This rule does not work and merely serves as an example of what I'd like to achieve. I could then use the exact same rule under many different hosts and get the correct result. Answers? Can this be done with mod_alias or does it require the more complex mod_rewrite? How can this be achieved using mod_alias or mod_rewrite? I'd prefer a mod_alias solution if possible. Clarifications I'm not staying on the same server. I'd like: http://example.com/terms/ - http://support.example.com/articles/terms/ https://secure.example.com/terms/ - http://support.example.com/articles/terms/ http://dev.example.com/terms/ - http://support.dev.example.com/articles/terms/ https://secure.dev.example.com/terms/ - http://support.dev.example.com/articles/terms/ I'd like to be able to use the same rule in the .htaccess file on both example.com and dev.example.com. In this situation I'd need to be able to refer to the HTTP_HOST as a variable rather than specifying it literally in the URL to which requests are redirected. I'll investigate the HTTP_HOST parameter as suggested but was hoping for a working example.

    Read the article

< Previous Page | 242 243 244 245 246 247 248 249 250 251 252 253  | Next Page >