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  • codeigniter differentiate field names in JOINed tables

    - by Patrick
    Hi, I need to retrieve data from two tables. the first is a list of events, the second is a list of venues. I have a fields with the same name in both tables: events.venue (which is an ID) and venues.venue is the name of the place, say "blues bar". The tables can be joined on events.venue = venues.id. Snippet of my model: $this->db->select('events.*, venues.*'); $this->db->join('venues', 'events.venue = venues.id'); if ($date != 'all') { $this->db->where('date', $date); } if ($keyword) { $this->db->like('description', $keyword); $this->db->or_like('band', $keyword); $this->db->or_like('venue', $keyword); $this->db->or_like('genre', $keyword); } $Q = $this->db->get('events'); if ($Q->num_rows() > 0) { foreach ($Q->result() as $row) { $data[] = $row; } } $Q->free_result(); return $data; Snippet of the View: foreach ($events as $row) { echo "<p>{$row->band} ({$row->genre})<br />"; echo "Playing at: {$row->venue}<br /></p>"; // echoes "blues bar" //more here... } 2 Questions: 1) Why does $row-venue echo venues.venue, instead of events.venue? B) how can I differentiate them? eg. What if I want to echo both events.venue and venues.venue? I can probably do something like "SELECT venues.venue as name_of_the_venue", but how can I do this when I've already selected *?

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  • Rails 3 HABTM Strange Association: Project and Employee in a tree.

    - by Mauricio
    Hi guys I have to adapt an existing model to a new relation. I have this: A Project has many Employees. the Employees of a Project are organized in some kind of hierarchy (nothing fancy, I resolved this adding a parent_id for each employee to build the 'tree') class Employee < AR:Base belongs_to :project belongs_to :parent, :class_name => 'Employee' has_many :childs, :class_name => 'Employee', :foreign_column => 'parent_id' end class Project < AR:Base has_many :employees, end That worked like a charm, now the new requirement is: The Employees can belong to many Projects at the same time, and the hierarchy will be different according to the project. So I though I will need a new table to build the HABTM, and a new class to access the parent_id to build the tree. Something like class ProjectEmployee < AR:Base belongs_to :project belongs_to :employee belongs_to :parent, :class_name => 'Employee' # <--- ?????? end class Project < AR:Base has_many :project_employee has_many :employees, :through => :project_employee end class Employee < AR:Base has_many :project_employee has_many :projects, :through => :project_employee end How can I access the parent and the childs of an employee for a given project? I need to add and remove childs as wish from the employees of a project. Thank you!

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  • jquery suspected naving convention problem

    - by donfigga
    Hi all im having provlem with this jquery function, the protion of the function that renames the id, class and name of the dropdown only works for the first dropdown, susequest ones do not work , any ideas, i suspect it may have something to do with naming convention as in cat.parent_id but it is required for asp.net mvc model binding. $(document).ready(function () { $("table select").live("change", function () { var id = $(this).attr('id'); if ($(this).attr('classname') != "selected") { var rowIndex = $(this).closest('tr').prevAll().length; $.getJSON("/Category/GetSubCategories/" + $(this).val(), function (data) { if (data.length > 0) { //problematic portion $("#" + id).attr('classname', 'selected'); $("#" + id).attr('name', 'sel' + rowIndex); $("#" + id).attr('id', 'sel' + rowIndex); var position = ($('table').get(0)); var tr = position.insertRow(rowIndex + 1); var td1 = tr.insertCell(-1); var td2 = tr.insertCell(-1); td1.appendChild(document.createTextNode('SubCategory')); var sel = document.createElement("select"); sel.name = 'parent_id'; sel.id = 'parent_id'; sel.setAttribute('class', 'unselected'); td2.appendChild(sel); $('#parent_id').append($("<option></option>").attr("value", "-1").text("-please select item-")); $.each(data, function (GetSubCatergories, Category) { $('#parent_id').append($("<option></option>"). attr("value", Category.category_id). text(Category.name)); }); sel.name = 'cat.parent_id'; sel.id = 'cat.parent_id'; } }); } }); });

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  • Display Consistent Value of an Item using MVVM and WPF

    - by Blake Blackwell
    In my list view control (or any other WPF control that will fit the situation), I would like to have one TextBlock that stays consistent for all items while another TextBlock that changes based on the value in the ObservableCollection. Here is how my code is currently laid out: XAML <ListView ItemsSource="{Binding Path=MyItems, Mode=TwoWay}"> <ListView.ItemTemplate> <DataTemplate> <StackPanel Orientation="Horizontal"> <TextBlock x:Name="StrVal" Text="{Binding StrVal}" /> <TextBlock x:Name="ConstVal" Text="{Binding MyVM.ConstVal}" /> </StackPanel> </DataTemplate> </ListView.ItemTemplate> </ListView> Model public class MyItem { public string StrVal { get; set; } } ViewModel public class MyVM { public MyVM() { ObservableCollection<MyItem> myItems = new ObservableCollection<MyItem>(); for (int i = 0 ; i < 10; i++) myItems.Add(new MyItem { StrVal = i.ToString()}); MyItems = myItems; ConstVal = "1"; } public string ConstVal { get; set; } public ObservableCollection<MyItem> MyItems { get; set; } } Code Behind this.DataContext = new MyVM(); The StrVal property repeats correctly in the ListView, but the ConstVal TextBlock does not show the ConstVal that is contained in the VM. I would guess that this is because the ItemsSource of the ListView is MyItems and I can't reference other variables outside of what is contained in the MyItems. My question is: How do I get ConstVal to show the value in the ViewModel for all listviewitems that will be controlled by the Observable Collection of MyItems.

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  • Implimenting Zend MVC for my existing site-first step?

    - by Joel
    Hi guys, OK-newbie question here. I'll try not to bombard SO with lots of questions-and hopefully this first one will show me the method I'll need to follow for subsequent conversions. I have a web-based calendar system that I developed, but it was coded for me procedurally (using PHP). I'm now working on learning OO and wanting to integrate this site into my localhost Zend Framework and slowly start converting parts to OO and the Zend Framework MVC process in particular. As I've said before, I understand that this will be a slow process, and when I'm done, I still probably won't have anything as OO friendly as if I had rewritten it from scratch, but I'd like to use this as a learning experience. So, I have dropped the whole site into my localhose/zend/Public folder, and everything is showing up great and linking to the database, etc. My question is-what would be the easiest first component to switch over to the MVC model? This site has a bit of everything-forms, login, authentication, some jQuery, etc. Can anyone point to a tutorial that would address what I'm trying to do? If indeed, a form would be one of the simpler things to switch, can someone walk me through those changes? Another idea is changing over all the header info, etc? Thanks for any pointers on where to start! EDIT: Also, I understand that SO is mainly for specific coding questions-I'm happy to share specific code, once I have an idea about which section to tackle first...

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  • better way of showing File Upload Errors?

    - by coure06
    Model: public class EmailAttachment { public string FileName { get; set; } public string FileType { get; set; } public int FileSize { get; set; } public Stream FileData { get; set; } } public class ContactEmail: IDataErrorInfo { public string Name { get; set; } public string Email { get; set; } public string Message { get; set; } public EmailAttachment Attachment { get; set; } public string Error { get { return null; } } public string this[string propName] { get { if (propName == "Name" && String.IsNullOrEmpty(Name)) return "Please Enter your Name"; if (propName == "Email"){ if(String.IsNullOrEmpty(Email)) return "Please Provide an Email Address"; else if(!Regex.IsMatch(Email, ".+\\@.+\\..+")) return "Please Enter a valid email Address"; } if (propName == "Message" && String.IsNullOrEmpty(Message)) return "Please Enter your Message"; return null; } }} And my controller file [AcceptVerbs(HttpVerbs.Post)] public ActionResult Con(ContactEmail ce, HttpPostedFileBase file) { return View(); } Now the Problem From the form i am getting Name,Email, Message and uploaded file. I can get validation errors automatically for Name,Email,Message using public string this[string propName]. How can i show validation errors if Attachment.FileSize 10000? If i write its code in public string this[string propName] i alwasy getting Attachment null. How can i fill Attachment Object of ContactEmail so that i can manage all errors on same place?

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  • How to correctly pass a float from C# to C++ (dll)

    - by RavelT
    I'm getting huge differences when I pass a float from C# to C++. I'm passing a dynamic float wich changes over time. With a debuger I get this: c++ lonVel -0.036019072 float c# lonVel -0.029392920 float I did set my MSVC++2010 floating point model to /fp:fast wich should be the standard in .NET if I'm not mistaken, but this didnt help. Now I cant give out the code but I can show a fraction of it. From C# side it looks like this: namespace Example { public class Wheel { public bool loging = true; #region Members public IntPtr nativeWheelObject; #endregion Members public Wheel() { this.nativeWheelObject = Sim.Dll_Wheel_Add(); return; } #region Wrapper methods public void SetVelocity(float lonRoadVelocity,float latRoadVelocity){Sim.Dll_Wheel_SetVelocity(this.nativeWheelObject,lonRoadVelocity,latRoadVelocity);} #endregion Wrapper methods } internal class Sim { #region PInvokes [DllImport(pluginName, CallingConvention=CallingConvention.Cdecl)] public static extern void Dll_Wheel_SetVelocity(IntPtr wheel,float lonRoadVelocity,float latRoadVelocity); #endregion PInvokes } } And in C++ side @ exportFunctions.cpp: EXPORT_API void Dll_Wheel_SetVelocity(CarWheel* wheel,float lonRoadVelocity,float latRoadVelocity){ wheel->SetVelocity(lonRoadVelocity,latRoadVelocity);} So any sugestions on what I should do in order to get 1:1 results or atleast 99% correct results.

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  • How to refactor models without breaking WPF views?

    - by Tim Murphy
    I've just started learning WPF and like the power of databinding it presents; that is ignoring the complexity and confusion for a noob. My concern is how do you safely refactor your models/viewmodels without breaking the views that use them? Take the following snippet of a view for example: <Grid> <ListView ItemsSource="{Binding Contacts}"> <ListView.View> <GridView> <GridViewColumn Header="First Name" DisplayMemberBinding="{Binding Path=FirstName}"/> <GridViewColumn Header="Last Name" DisplayMemberBinding="{Binding Path=FirstName}"/> <GridViewColumn Header="DOB" DisplayMemberBinding="{Binding Path=DateOfBirth}"/> <GridViewColumn Header="# Pets" DisplayMemberBinding="{Binding Path=NumberOfPets}"/> <GridViewColumn Header="Male" DisplayMemberBinding="{Binding Path=IsMale}"/> </GridView> </ListView.View> </ListView> </Grid> The list is bound to the Contacts property, IList(Of Contact), of the windows DataSource and each of the properties for a Contact is bound to a GridViewColumn. Now if I change the name of the NumberOfPets property in the Contact model to PetCount the view will break. How do I prevent the view breaking?

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  • Tools for Automated Source Code Editing

    - by Steve
    I'm working on a research project to automatically modify code to include advanced mathematical concepts (like adding random effects into a loop or encapsulating an existing function with a new function that adds in a more advanced physical model). My question to the community is: are there are any good tools for manipulating source code directly? I want to do things like Swap out functions Add variable declarations wherever they are required Determine if a function is multiplied by anything Determine what functions are called on a line of code See what parameters are passed to a function and replace them with alternatives Introduce new function calls on certain lines of code Wherever possible just leaving the rest of the code untouched and write out the results I never want to actually compile the code I only want to understand what symbols are used, replace and add in a syntactically correct way, and be able to declare variables at the right position. I've been using a minimal flex/bison approach with some success but I do not feel the it is robust. I hate to take on writing a full language parser just to add some new info to the end of a line or the top of a function. It seems like this is almost what is going to be required but it also seems like there should be some tools out there to do these types of manipulations already. The code to be changed is in a variety of languages, but I'm particularly interested in FORTRAN. Any thoughts?

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  • BufferedImage & ColorModel in Java

    - by spol
    I am using a image processing library in java to manipulate images.The first step I do is I read an image and create a java.awt.Image.BufferedImage object. I do it in this way, BufferedImage sourceImage = ImageIO.read( new File( filePath ) ); The above code creates a BufferedImage ojbect with a DirectColorModel: rmask=ff0000 gmask=ff00 bmask=ff amask=0. This is what happens when I run the above code on my macbook. But when I run this same code on a linux machine (hosted server), this creates a BufferedImage object with ColorModel: #pixelBits = 24 numComponents = 3 color space = java.awt.color.ICC_ColorSpace@c39a20 transparency = 1 has alpha = false isAlphaPre = false. And I use the same jpg image in both the cases. I don't know why the color model on the same image is different when run on mac and linux. The colormodel for mac has 4 components and the colormodel for linux has 3 components.There is a problem arising because of this, the image processing library that I use always assumes that there are always 4 components in the colormodel of the image passed, and it throws array out of bounds exception when run on linux box. But on macbook, it runs fine. I am not sure if I am doing something wrong or there is a problem with the library. Please let me know your thoughts. Also ask me any questions if I am not making sense!

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  • Post JSON array to mvc controller

    - by Yustme
    I'm trying to post a JSON array to a mvc controller. But no matter what i try, everything is 0 or null. I have this table that contains textboxes. I need from all those textboxes it's ID and value as an object. This is my java code: $(document).ready(function () { $('#submitTest').click(function (e) { var $form = $('form'); var trans = new Array(); var parameters = { TransIDs: $("#TransID").val(), ItemIDs: $("#ItemID").val(), TypeIDs: $("#TypeID").val(), }; trans.push(parameters); if ($form.valid()) { $.ajax( { url: $form.attr('action'), type: $form.attr('method'), data: JSON.stringify(parameters), dataType: "json", contentType: "application/json; charset=utf-8", success: function (result) { $('#result').text(result.redirectTo) if (result.Success == true) { return fase; } else { $('#Error').html(result.Html); } }, error: function (request) { alert(request.statusText) } }); } e.preventDefault(); return false; }); }); This is my view code: <table> <tr> <th>trans</th> <th>Item</th> <th>Type</th> </tr> @foreach (var t in Model.Types.ToList()) { { <tr> <td> <input type="hidden" value="@t.TransID" id="TransID" /> <input type="hidden" value="@t.ItemID" id="ItemID" /> <input type="hidden" value="@t.TypeID" id="TypeID" /> </td> </tr> } } </table> This is the controller im trying to receive the data to: [HttpPost] public ActionResult Update(CustomTypeModel ctm) { return RedirectToAction("Index"); } What am i doing wrong?

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  • Custom bean instantiation logic in Spring MVC

    - by Michal Bachman
    I have a Spring MVC application trying to use a rich domain model, with the following mapping in the Controller class: @RequestMapping(value = "/entity", method = RequestMethod.POST) public String create(@Valid Entity entity, BindingResult result, ModelMap modelMap) { if (entity== null) throw new IllegalArgumentException("An entity is required"); if (result.hasErrors()) { modelMap.addAttribute("entity", entity); return "entity/create"; } entity.persist(); return "redirect:/entity/" + entity.getId(); } Before this method gets executed, Spring uses BeanUtils to instantiate a new Entity and populate its fields. It uses this: ... ReflectionUtils.makeAccessible(ctor); return ctor.newInstance(args); Here's the problem: My entities are Spring managed beans. The reason for this is to inject DAOs on them. Instead of calling new, I use EntityFactory.createEntity(). When they're retrieved from the database, I have an interceptor that overrides the public Object instantiate(String entityName, EntityMode entityMode, Serializable id) method and hooks the factories into that. So the last piece of the puzzle missing here is how to force Spring to use the factory rather than its own BeanUtils reflective approach? Any suggestions for a clean solution? Thanks very much in advance.

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  • Optimize INSERT / UPDATE / DELETE operation

    - by clime
    I wonder if the following script can be optimized somehow. It does write a lot to disk because it deletes possibly up-to-date rows and reinserts them. I was thinking about applying something like "insert ... on duplicate key update" and found some possibilities for single-row updates but I don't know how to apply it in the context of INSERT INTO ... SELECT query. CREATE OR REPLACE FUNCTION update_member_search_index() RETURNS VOID AS $$ DECLARE member_content_type_id INTEGER; BEGIN member_content_type_id := (SELECT id FROM django_content_type WHERE app_label='web' AND model='member'); DELETE FROM watson_searchentry WHERE content_type_id = member_content_type_id; INSERT INTO watson_searchentry (engine_slug, content_type_id, object_id, object_id_int, title, description, content, url, meta_encoded) SELECT 'default', member_content_type_id, web_member.id, web_member.id, web_member.name, '', web_user.email||' '||web_member.normalized_name||' '||web_country.name, '', '{}' FROM web_member INNER JOIN web_user ON (web_member.user_id = web_user.id) INNER JOIN web_country ON (web_member.country_id = web_country.id) WHERE web_user.is_active=TRUE; END; $$ LANGUAGE plpgsql; EDIT: Schemas of web_member, watson_searchentry, web_user, web_country: http://pastebin.com/3tRVPPVi. (content_type_id, object_id_int) in watson_searchentry is unique pair in the table but atm the index is not present (there is no use for it). This script should be run at most once a day for full rebuilds of search index.

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  • How to understand other people's CSS architectures?

    - by John
    I am reasonably good with CSS. However, when working with someone else's CSS, it's difficult for me to see the "bigger picture" in their architecture (but i have no problem when working with a CSS sheet I wrote myself). For example, I have no problems using Firebug to isolate and fix cross browser compatibility issues, or fixing a floating issue, or changing the height on a particular element. But if I'm asked to do something drastic such as, "I want the right sidebars of pages A, B, C and D to have a red border. I want the right side bars of pages E, F and G to have a blue border if and only if the user mouses over", then it takes me time a long time to map out all the CSS inheritance rules to see the "bigger picture". For some reason, I don't encounter the same difficulty with backend code. After a quick debriefing of how a feature works, and a quick inspection of the controller and model code, I will feel comfortable with the architecture. I will think, "it's reasonable to assume that there will be an Employee class that inherits from the Person Class that's used by a Department controller". If I discover inconvenient details that aren't consistent with overall architectural style, I am confident that I can hammer things back in place. With someone else's CSS work, it's much harder for me to see the "relationships" between different classes, and when and how the classes are used. When there are many inheritance rules, I feel overwhelmed. I'm having trouble articulating my question and issues... All I want to know is, why is it so much harder for me to see the bigger picture in someone else's CSS architecture than compared to someone else's business logic layer? **Does it have any thing to do with CSS being a relatively new technology, and there aren't many popular design patterns?

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  • 1.8.x Ruby on Rails RESTful nested admin page and form_for problems

    - by Loomer
    So I am creating a website that I want to have an admin directory in rails 1.8.x and I'm struggling a bit to get the form_for to link to the right controller. I am trying to be RESTful. What I basically want is an admin page that has a summary of actions which can then administer sub models such as: /admin (a summary of events) /admin/sales (edit sales on the site) /admin/sales/0 (the normal RESTful stuff) I can't use namespaces since they were introduced in Rails 2.0 (production site that I don't want to mess with updating rails and all that). Anyway, what I have in the routes.rb is: map.resource :admin do |admin| admin.resources :sales end I am using the map.resource as a singleton as recommended by another site. The problem comes in when I try to use the form_for to link to the subresource RESTfully. If i do : form_for(:sales, @sale) it never links to the right controller no matter what I try. I have also tried: form_for [@admin, @sale] do |f| and that doe not work either (I am guessing since admin is a singleton which does not have a model, it's just a placeholder for the admin controller). Am I supposed to add a prefix or something? Or something into the sales controller to specify that it is a subcontroller to admin? Is there an easier way to do this without manually creating a bunch of routes? Thanks for any help.

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  • Problem in mutiple :dependent=> :destroy when multiple polymorphic is true

    - by piemesons
    I have four models question, answer, comment and vote.Consider it same as stackoverflow. Question has_many comments Answers has_many comments Questions has_many votes answers has_many votes comments has_many votes Here are the models (only relevant things) class Comment < ActiveRecord::Base belongs_to :commentable, :polymorphic => true has_many :votes, :as => :votable, :dependent => :destroy end class Question < ActiveRecord::Base has_many :comments, :as => :commentable, :dependent => :destroy has_many :answers, :dependent => :destroy has_many :votes, :as => :votable, :dependent => :destroy end class Vote < ActiveRecord::Base belongs_to :votable, :polymorphic => true end class Answer < ActiveRecord::Base belongs_to :question, :counter_cache => true has_many :comments, :as => :commentable , :dependent => :destroy end Now the problem is whenever i am trying to delete any question/answer/comment its giving me an error NoMethodError in QuestionsController#destroy undefined method `each' for 0:Fixnum if i remove this line from any of the model (question/answer/comment) has_many :votes, :as => :votable, :dependent => :destroy then it works perfectly. It seems there is a problem while deleting the records active record is not able to find out the proper path because of multiple joins within the tables.

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  • Flash Player, security: If a URL starts with "http://" will the SWF always be loaded into REMOTE san

    - by Pavel
    Seems to be a question for a Flash security guru. Suppose we are loading an external SWF movie with MovieClipLoader.loadMovie(url:String) Is it safe to assume that if url starts with "http://", the movie will be loaded in REMOTE sandbox? We need to tell local SWFs from remote ones to close a security hole. If you need the context read on. We have developed a Projector, written in C++ embedding Flash Player ActiveX. Our Flash application runs inside the Projector. Soon we want to give our users a way to create plugins for the application. The plugins are obviously will be SWF movies. The case I'm afraid of is the following. A bad person creates a malicious evil.swf pretending it to be nice plugin for our app. In case evil.swf is loaded from the local file system it is granted an access to the whole MovieClip tree and Projector API, opening C++ file access operations. On the other hand if evil.swf is loaded from the internet, remotely, it will be locked in REMOTE sandbox by Flash security model. Because of this, we need a reliable way to tell local SWF from remote one before loading it. And we must not make a mistake. So again, is it safe to assume that if url begins with "http://", the clip will be loaded inside REMOTE sandbox?

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  • query not displaying proper result

    - by ravindra
    In my Rails 3 project I have the following code for My controller: class TasksController < ApplicationController def today @tasks = Task.today @task = Task.new respond_to do |format| format.html { render :text=> "Sorry , you don't have any task pending today." } format.html # new.html.erb format.xml { render :xml => @tasks } end end def this_week @tasks = Task.this_week @task = Task.new respond_to do |format| format.html { render :text => "Sorry , No content for selected period." } format.html # new.html.erb format.xml { render :xml => @tasks } end end end My model: class Task < ActiveRecord::Base def self.today Task.where(:due_date => "Date.today" , :task_status => "open").order("due_date ASC") end def self.this_week Task.where(:due_date =>"Time.now.this_week" , :task_status => "open" ).order("due_date ASC") end end Why it does not displaying anything in the relative view. Please help me. Thanks

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  • WCF publish/subscribe service, and ASP.NET MVC client

    - by d3j4vu
    I managed to develop a custom WCF service, using the publish / subscribe model, and hosted inside a managed windows service. Everything's working. I developed an interface as the service contract implementing a method definition marked as a non-one way operation contract (OperationContract(IsOneWay = false)]. This, to make possible returns an instance of a custom class derived from System.Web.Mvc.ActionResult. In the MVC app, event fires ok. It wraps inside an action method, (just the one defined in the interface), but, and this is my current problem, i believe that something relative to the execution context of the windows service (and the hosted wcf counterpart) blocks the execution of the action method in the MVC app. This is what i have until now (some pieces ripped off just to be more clear): /// Method definition for the contract's service. Maps to a MVC ActionMethod. [OperationContract(IsOneWay = false)] ActionResult Imagen(string data, CustomActionResult result); The class to hold an ActionResult derived class instance: public class ServiceEventArgsMvc : ServiceEventArgs { /// <summary> /// /// </summary> public CustomActionResult Result { get; set; } } And the code in the MVC client app: /// <summary> /// Just a simple class to hold an abstract ActionResult derived class instance. /// </summary> public ActionResult Image(string data, CustomActionResult result) { ViewData["data"] = data; return View(); } Ok. ActionMethod sucessfully executes...but when it's done (and usually expected obtain a reditection to a View named Image, like the action method), the WCF service throws a Timeout exception, making clear that he's still waiting for a response from the MVC client. The response never arrives, so the MVC app never finish his work (redirect to the "Image" view as expected). Any ideas?. Guess i'm missing something very simple, but i don't know what it could be. This is drivin' me nuts.

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  • RoR ActiveRecord f.select nil method error

    - by sellis6688
    Whenever I use an f.select statement to determine assignment_id(or student_id), and I should get a validation error, I get this error instead of the validation message: You have a nil object when you didn't expect it! You might have expected an instance of Array. The error occurred while evaluating nil.collect Extracted source (around line #11): 8: </p> 9: <p> 10: <%= f.label 'Assignment:' %><br /> 11: <%= f.select(:assignment_id, @assignments.collect {|p| [p.ass_num, p.id]})%> 12: </p> 13: <p> 14: <%= f.label 'First Student:' %><br /> My grades model: class Grade < ActiveRecord::Base has_and_belongs_to_many :students belongs_to :assignment validates_presence_of :score, :assignment_id, :student_id validates_numericality_of :score, :greater_than_or_equal_to => 0, :less_than_or_equal_to => 100, :allow_nil => true validates_uniqueness_of :student_id, :scope => :assignment_id end If I use a text_field, I don't get the error... but there's far too many students for that. Neither @assignments nor @students are nil. Any suggestions?

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  • Why do I get this exception? {An item with the same key has already been added."})

    - by Alan
    Aknittel NewSellerID is the result of a lookup on tblSellers. These tables (tblSellerListings and tblSellers) are not "officially" joined with a foreign key relationship, either in the model or in the database, but I want some referential integrity maintained for the future. So my issue remains. Why do I get the exception ({"An item with the same key has already been added."}) with this code, if I don't begin each iteration of the foreach loop with a new ObjectContext and end it with SaveChanges, which I think will affect performance. Also, could you tell me why ORCSolutionsDataService.tblSellerListings (An ADO.NET DataServices/WCF object is not IDisposable, like LINQ to Entities?? ============================================== // Add listings to previous seller int NewSellerID = 0; // Look up existing Seller key using SellerUniqueEBAYID var qryCurrentSeller = from s in service.tblSellers where s.SellerEBAYUserID == SellerUserID select s; foreach (var s in qryCurrentSeller) NewSellerID = s.SellerID; // Save the selected listings for this seller foreach (DataGridViewRow dgr in dgvRows) { ORCSolutionsDataService.tblSellerListings NewSellerListing = new ORCSolutionsDataService.tblSellerListings(); NewSellerListing.ItemID = dgr.Cells["txtSellerItemID"].Value.ToString(); NewSellerListing.Title = dgr.Cells["txtSellerItemTitle"].Value.ToString(); NewSellerListing.CurrentPrice = Convert.ToDecimal(dgr.Cells["txtSellerItemPrice"].Value); NewSellerListing.QuantitySold = Convert.ToInt32(dgr.Cells["txtSellerItemSold"].Value); NewSellerListing.EndTime = Convert.ToDateTime(dgr.Cells["txtSellerItemEnds"].Value); NewSellerListing.CategoryName = dgr.Cells["txtSellerItemCategory"].Value.ToString(); NewSellerListing.ExtendedPrice = Convert.ToDecimal(dgr.Cells["txtExtendedReceipts"].Value); NewSellerListing.RetrievedDtime = Convert.ToDateTime(dtSellerDataRetrieved.ToString()); NewSellerListing.SellerID = NewSellerID; service.AddTotblSellerListings(NewSellerListing); } service.SaveChanges(); } catch (Exception ex) { MessageBox.Show("Unable to add a new case. Exception: " + ex.Message); }

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  • Can anyone give me a sample java socket programming for doing a peer to peer for 3 systems?

    - by Sadesh Kumar N
    I am doing an university project. I need some sample programs on peer to peer programs in java socket programming. Every where people are telling to add a server socket in the client program. I am in a confusion. Can a single program having server socket and client socket will do or i have to create two programs of one initiating a system and another peer program running thrice to solve the problem. or i need to create three programs for three peer systems. I am not clear on the architecture of building peer to peer programs using java sockets. Can some one help me giving a simple program on how to create a peer to peer connection between three systems. I know how to do a socket program for client server model and clear on the concept. But creating a peer to peer architecture sounds complex for me to understand. I also referred this thread. developing peer to peer in java The person commented second says" To make peer2peer app each client opens server socket too. When client A wishes to connect to client B it just connects to its socket. " Need some more sample and an explanation on how peer to peer java socket program works I dont want any external api like jxta to do this task. I need a clear picture on how it works alone with an example.

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  • Get Form Input via Ajax

    - by user3651491
    I have a jqgrid plugin which I call via Ajax. I have index.php and a getGridData.php. How will I pass form input in getGridData.php via ajax and use it in getGridData.php? I tried serialize but I can't pass or access it on getGridData.php. I need it as parameters for mysql. Here's my code. <script language="javascript" type="text/javascript"> function jgGrid() { $(document).ready(function () { $("#grid").jqGrid({ url: "inc/Controller/getGridData.php"+$("#thisForm").serialize(), data : formData, datatype: "json", mtype: "POST", colNames: ["SiteID", "TerminalID", "TransactionType", "Amount", "ServiceStatus"], colModel: [ { name: "SiteID"}, { name: "TerminalID"}, { name: "TransactionType"}, { name: "Amount"}, { name: "ServiceStatus"}, ], pager: "#pager", rowNum: 10, rowList: [10,20], sortname: "SiteID", sortorder: "asc", height: 'auto', viewrecords: true, gridview: true, caption: "" }); }); } </script> getGridData.php include('../Model/Queries.php'); $cardnumber = $_POST['cardnumber']; $transact_type = $_POST['transact_type']; $fromdate = $_POST['fromdate']; $todate = $_POST['todate']; $loyalty = new Queries(); $get_mid = $loyalty->loyaltyConn($cardnumber); $somedata = json_encode($loyalty->nposConn($get_mid, $transact_type, $fromdate, $todate)); echo $somedata;

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  • content_tag_for a collection in Rails?

    - by Nick
    I have a Post model. Posts have many Comments. I want to generate a <ul> element for post.comments using content_tag_for. Ideally, it'd produce <ul id="comments_post_7" class="comments"> ... </ul> where 7 is the ID of the Post. The closest I can get uses <% content-tag-for :ul post, :comments do %> which produces <ul id="comments_post_7" class="post"> ... </ul> which is pretty close, except for the class="post". Using :class => :comments in the content_tag_for yields class="post comments", but I just want class="comments". It seems logical that I'd be able to use something like <% content_tag_for :ul post.comments do %> but, sadly, that yields <ul id="array_2181653100" class="array"> ... </ul> I've searched far and wide. I feel like I'm missing some elegant way to do this. Am I? Because, seriously, <ul id="comments_post_<%= post.id %>" class="comments"> is painful.

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  • Parallelizing L2S Entity Retrieval

    - by MarkB
    Assuming a typical domain entity approach with SQL Server and a dbml/L2S DAL with a logic layer on top of that: In situations where lazy loading is not an option, I have settled on a convention where getting a list of entities does not also get each item's child entities (no loading), but getting a single entity does (eager loading). Since getting a single entity also gets children, it causes a cascading effect in which each child then gets its children too. This sounds bad, but as long as the model is not too deep, I usually don't see performance problems that outweigh the benefits of the ease of use. So if I want to get a list in which each of the items is fully hydrated with children, I combine the GetList and GetItem methods. So I'll get a list and then loop through it getting each item with the full cascade. Even this is generally acceptable in many of the projects I've worked on - but I have recently encountered situations with larger models and/or more data in which it needs to be more efficient. I've found that partitioning the loop and executing it on multiple threads yields excellent results. In my first experiment with a list of 50 items from one particular project, I did 5 threads of 10 items each and got a 3X improvement in time. Of course, the mileage will vary depending on the project but all else being equal this is clearly a big opportunity. However, before I go further, I was wondering what others have done that have already been through this. What are some good approaches to parallelizing this type of thing?

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