Search Results

Search found 29508 results on 1181 pages for 'object initializers'.

Page 904/1181 | < Previous Page | 900 901 902 903 904 905 906 907 908 909 910 911  | Next Page >

  • Rails Model has_many with multiple foreign_keys

    - by Kenzie
    Relatively new to rails and trying to model a very simple family "tree" with a single Person model that has a name, gender, father_id and mother_id (2 parents). Below is basically what I want to do, but obviously I can't repeat the :children in a has_many (the first gets overwritten). class Person < ActiveRecord::Base belongs_to :father, :class_name => 'Person' belongs_to :mother, :class_name => 'Person' has_many :children, :class_name => 'Person', :foreign_key => 'mother_id' has_many :children, :class_name => 'Person', :foreign_key => 'father_id' end Is there a simple way to use has_many with 2 foreign keys, or maybe change the foreign key based on the object's gender? Or is there another/better way altogether? Thanks!

    Read the article

  • Can I write to different jetty databases using JPA that is using the same "entity class"

    - by Per
    I am using Java persistance and there EntityManager class and have it assigned to storage a class object that shall be written to the database. My problem is that I want to write to different databases using the same storage class. My solution to that was to write a StorageManagerfactory that has a Map holding all EntityManagers. The solution looked good until I looked at the databases and realized that all information (undepending of the Map, which gets the correct value) was written to the same database (one of the initialised in the Map). So my question is: Can I write to different databases using JPA that is using the same storage class (the class holding the structure of my database)? Thanks

    Read the article

  • const keyword in Objective-c

    - by user392412
    int main(int argc, char *argv[]) { @autoreleasepool { const int x = 1; const NSMutableArray *array1 = [NSMutableArray array]; const NSMutableString *str1 = @"1"; NSString * const str2 = @"2"; // x = 2; compile error [array1 addObject:@"2"]; // ok // [str1 appendString:@"2"]; // runtime error // Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'Attempt to mutate immutable object with appendString:' // str2 = @"3"; compile error } } my Question is Why array1 addObject is legal and why str1 appendString is forbidden?

    Read the article

  • SQL Stored Procedure fired from C# Code-Behind not working on UPDATE

    - by CSSHell
    I have a stored procedure called from a C# code-behind. The code fires but the update command does not get performed. The stored procedure, if run directly, works. I think I am having a brain fart. Please help. :) CODEBEHIND protected void btnAbout_Click(object sender, EventArgs e) { SqlConnection myConnection = new SqlConnection(strConnection); SqlCommand myCommand = new SqlCommand("spUpdateCMSAbout", myConnection); myConnection.Open(); myCommand.CommandType = CommandType.StoredProcedure; myCommand.Parameters.Add("@AboutText", SqlDbType.NVarChar, -1).Value = txtAbout.Text.ToString(); myCommand.ExecuteNonQuery(); myConnection.Close(); } STORED PROCEDURE ALTER PROCEDURE fstage.spUpdateCMSAbout ( @AboutText nvarchar(max) ) AS BEGIN SET NOCOUNT ON; UPDATE fstage.staticCMS SET About = @AboutText; END HTML <asp:Button ID="btnAbout" runat="server" Text="Save" CausesValidation="False" onclick="btnAbout_Click" UseSubmitBehavior="False" /> C# .NET 4.0

    Read the article

  • Iterating over hashmap in JSP in struts application

    - by Rozer
    I have a HashMap object that I am getting on a JSP page. HashMap<Integer,Gift_product> gift_hm = new HashMap<Integer,Gift_product>(); gift_hm.put(17,new Gift_product("doll",67)); Now I need to iterate this and display content on JSP. The Gift_product class contains two fields: name and price. JSP output should be serial no. product name price 17 Doll 67 How can I achieve it?

    Read the article

  • How to get a dynamic attribute name in cfloop over query in ColdFusion

    - by Kip
    I'm inside a cfloop over a query. I want to get an attribute, but I won't know what that attribute will be until runtime. Using #qryResult[MyAttr]# fails with the error "Complex object types cannot be converted to simple values." What is the syntax for doing this? Here is a simplified example: <cfquery datasource="TestSource" name="qryResult"> SELECT * FROM MyTable </cfquery> <cfloop query="qryResult"> <cfset MyAttr="autoid" /> <cfoutput> Test 1: #qryResult.autoid# <br/> <!--- succeeds ---> Test 2: #qryResult[MyAttr]# <br/> <!--- fails ---> </cfoutput> </cfloop>

    Read the article

  • C# - Why can't I enforce derived classes to have parameterless constructors?

    - by FrisbeeBen
    I am trying to do the following: public class foo<T> where T : bar, new { _t = new T(); private T _t; } public abstract class bar { public abstract void someMethod(); // Some implementation } public class baz : bar { public overide someMethod(){//Implementation} } And I am attempting to use it as follows: foo<baz> fooObject = new foo<baz>(); And I get an error explaining that 'T' must be a non-abstract type with a public parameterless constructor in order to use it as parameter 'T' in the generic type or method. I fully understand why this must be, and also understand that I could pass a pre-initialized object of type 'T' in as a constructor argument to avoid having to 'new' it, but is there any way around this? any way to enforce classes that derive from 'bar' to supply parameterless constructors?

    Read the article

  • Get detailed information on FileSystemEventArgs.ChangeType

    - by case23
    I using the FileWatcher Class to locate changes on Files in a specific Folder. I managed to detect Changes on Files but not detailed Information. On the WatcherChangeTypes Enumeration Page http://msdn.microsoft.com/en-us/library/t6xf43e0%28v=VS.100%29.aspx they write the Change Type detects the changes include: changes to size, attributes, security settings, last write, and last access time. Is there a way to detect which kind of change happened? Thats the Event handler method i use. private void OnChanged(object source, FileSystemEventArgs e) { Console.WriteLine("File: " + e.FullPath + " Change Type: " + e.ChangeType); } Thank you in advance Case

    Read the article

  • jquery: How can I trigger click() without editing the element state?

    - by user280381
    I need to trigger a click function assigned to a checkbox, but without actually changing it's checked state (which click() does). Scenario: I have a form with several checkboxes that when selected reveal a textarea. This works fine, but I also need to call the click() function on $(document).ready() My code is below, please note I have very limited access to changing the generated html. I have an object (admin_panels) which will store each checkbox and the texarea it should bring up. var admin_panels = {"checkbox-id" : "textarea-id"}; $(document).ready(function(){ for (var elem in admin_panels) { $("#" + elem).click(admin_slide); // $("#" + elem).click(); } }) function admin_slide() { if ($(this).is(":checked")) { $("#" + admin_panels[this.id] + "-wrapper").slideDown(); }else{ $("#" + admin_panels[this.id] + "-wrapper").slideUp(); } } Thanks

    Read the article

  • Store data in an inconvenient table or create a derived table?

    - by user1705685
    I have a certain predefined database structure that I am stuck with. The question is whether this structure is OK for ORM or I whether should add a processing layer that would create a more convenient structure every time something is inserted into the original DB. To simplify, here's what it kind of looks like. I have a person table: PersonId Name And I have a properties table: PersonId PropertyType PropertyValue So, for person John Doe... (1, 'John Doe') ...I could have three properties: (1, 'phone', '555-55-55'), (1, 'email', '[email protected]), (1, 'type', 'employee') By using ORM I would like to get a "person" object that would have properties "name", "phone", "email", "type". Can Propel do that? How efficient is it? Is it a better idea to create a table with columns "phone", "email", "type" and fill it automatically as new rows are inserted into the properties table?

    Read the article

  • After C++ - Python or Java?

    - by carleeto
    I'm fast approaching the point in my coding where I would like to quickly write object oriented code in languages other than C++ for a variety of reasons. After a lot of research, my choices have pretty much narrowed down to Python and Java. I'm leaning towards Python because of its relationship to C, but with Java, from what I can see, I get a good introduction to using and creating test suites with Eclipse - there is also Processing which is pulling me towards Java. I'm not the kind of guy to tackle two languages at once, so which one would you recommend and why? What I want at the end is to have an additional language I can use for rapid development. Ease of learning isn't important to me as I'm willing to put in the time regardless. Ability to use the new language widely is.

    Read the article

  • What's a unit test? [closed]

    - by Tyler
    Possible Duplicates: What is unit testing and how do you do it? What is unit testing? I recognize that to 95% of you, this is a very WTF question. So. What's a unit test? I understand that essentially you're attempting to isolate atomic functionality but how do you test for that? When is it necessary? When is it ridiculous? Can you give an example? (Preferably in C? I mostly hear about it from Java devs on this site so maybe this is specific to Object Oriented languages? I really don't know.) I know many programmers swear by unit testing religiously. What's it all about? EDIT: Also, what's the ratio of time you typically spend writing unit tests to time spent writing new code?

    Read the article

  • WPF C#: Starting crash due to client 'Region and Language' settings

    - by FrieK
    Hi, I'm working on a WPF C# application, and it seems to crash with a few random people. So eventually I found out it was the 'Region and Language' settings that was responsible. For example, if I were to set my Format to English (United States) it will work, if I set it to Swedish (Sweden) it will crash from the start. When I test this in Visual Studio 2010 it gives error 'TypeInitializationException'. More precisely it does it here (it doesn't get passed the InitializeComponent() void): private void RadioButton_Checked(object sender, RoutedEventArgs e) { Info.SortOrder = SortBy.Rank; } It claims the error at the first line, which is just setting an enum value to a variable. I guess it's just doing it there because it's the first thing it makes, or something. Anyone has any idea how to fix this? I've searched around but can't seem to find out how :( Any help is much appreciated! Thanks

    Read the article

  • How to access radioButton individual items?

    - by vikitor
    Hello, I've got 2 radio button groups showed differently depending on the value selected on another radio button. The thing is that I would like to set the default value of the group to the first element in the radiobutton group, but when I change from the other radio button it preserves the value previously selected, when I want it to be reset to the default value. I've been searching in the javascript repository but apparently I cannot access like it says with radio[1].checked = true... It says that radio[1] is undefined, but radio is an HTML Input element object. I'm accessing it from a different file, but var radio = document.getElementById("radio") works, but I can't access the individual radiobuttons. Thank you in advance

    Read the article

  • After grouping by, can I refer to the elements of the original IEnumerable in a LINQ query?

    - by michielvoo
    Example: from OriginalObject in ListOfOriginalObjects group new CustomObject { X = OriginalObject.A, Y = OriginalObject.B } by OriginalObject.Z into grouping select new GroupOfCustomObjects { Z = grouping.Key, C = OriginalObject.C, group = grouping } In the select part of the query, I'd like to add a property (OriginalObject.C) to the type GroupOfCustomObjects. But it seems that OriginalObject is out of scope in that part of the query. I can sort of understand why, since I am not grouping on that property and I am also not making that property part of CustomObject that I'm grouping. One workaround is to add a property C to CustomObject and the in the GroupOfCustomObjects read the value of the first CustomObject in the grouping. My issue with that is that I'm adding a property to an object that doesn't need it (CustomObject), just to be able to add it to the GroupOfCustomObjects. I hope I have explained this properly! Is there a way to refer to the OriginalObject that the query starts with? Thanks!

    Read the article

  • How can I receive the "scroll box" type scroll events from a DataGridView?

    - by Simon
    I have a DataGridView, and I'm listening to its Scroll event. This gives me a ScrollEventArgs object whose Type member is supposed to tell me the type of scroll event that has occurred. On the MSDN documentation page it says I should be able to detect movement of the scroll box by listening for events with types ThumbPosition, ThumbTrack, First, Last and EndScroll. However, when I drag the scroll box, I only get events of type LargeDecrement and LargeIncrement. How do I get access to the ThumbPosition, ThumbTrack, First, Last and EndScroll events?

    Read the article

  • Java Null Pointer Exception :-(

    - by John-Michael Reed
    I've got a Null Pointer Exception in my main that just won't go away and I'm totally out of ideas. The error is on the line "Board[x][y].color = 2;" in which Board is a public, static array of piece objects that contain instance variables like the one "color" that is being set to 2 in the above statement. Pieces is not static - that is there are many different copies of pieces, each with its own data, but only one board. The array has been initialized and defined as both public Piece[][] Board = new Piece[8][8] and public static Piece[][] Board = new Piece[8][8], but no matter how I mess around with it (getting rid of static, putting the variable in another object, etc.), I can't seem to get the error to go away. Help?

    Read the article

  • IPhone CoreData: How should I relate many child entities to thier parents

    - by Robert
    I am trying to import data from a database that uses primary key / forign key relations to a core data database in Xcode. I have code that creates hundreds of child entities in a managed object context: Each child has an ID that corresponds to a parent. child1 parentID = 3 child2 parentID = 17 child3 parentID = 17 ... childn parentID = 5 I now need to relate each child to its parent. The parents are all stored in persistent memory. My first thought was to preform a fetch for each child to get its parent. However, I think this would be slow. Am I correct? How should I do this instead?

    Read the article

  • CoreData and UITableViewController Problem

    - by eemceebee
    Hi I have a app that works with Core Data. The data has a field with a date and I would like to show every entry of a month in a seperate section. How do I actually get the data ? I use a NSFetchedResultsController to get the data and use this : - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { id <NSFetchedResultsSectionInfo> sectionInfo = [[_fetchedResultsController sections] objectAtIndex:section]; return [sectionInfo numberOfObjects]; } to get the rows and this : - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { MyInfoObject *info = [_fetchedResultsController objectAtIndexPath:indexPath]; } to get my actually data object. Thanks

    Read the article

  • mysql_fetch_object on complex objects

    - by Arsenal
    Say for example I have the follwoing DB structure Table book id title ... Table Author id name ... Table BookAuthor id bookid authorid And in PHP I have the following object class Book { var $id; var $title; var $authors = array(); function Book() {} } class Author { var $id; var $name; function Author(){} } Now, would it be possible using mysql_fetch_object to retrieve the bookobject including the authors as an array of author objects? If it's possible I'm pretty sure you'll need the basic inner join query SELECT * FROM tblbook INNER JOIN tblbookauthor on ... (wel you get the point) Is it possible? thanks!

    Read the article

  • allocator with no template

    - by Merni
    Every stl container take an allocator as a second object, template < class T, class Allocator = allocator<T> > class vector; If you write your own class It is possible to use your own allocator. But is it possible to write your own allocator without using templates? For example, writing this function is not easy if you are not allowed to use templates pointer allocate(size_type n, const_pointer = 0) { void* p = std::malloc(n * sizeof(T)); if (!p) throw std::bad_alloc(); return static_cast<pointer>(p); } Because how could you know the size of T?

    Read the article

  • compiling boost based application using cron

    - by user303544
    Hi All, I am building some boost based application for various embedded targets. I have developed a script which can build my application with different toolchain for several targets. This script works fine when I run it from command line but if it is invoked from cron it always fails to link the object files. My application has dependency on openssl. Can anyone please give some idea? What would be the root cause of this kind of behavior? Thanks in advance.

    Read the article

  • How to format complex chained Linq statements for readibility?

    - by Joan Venge
    I have some code like this: var effects = xElement.Elements ( "Effects" ).Elements ( "Effect" ).Select ( e => new Effect ( ( EffectType ) Enum.Parse ( typeof ( EffectType ), ( string ) e.Elements ( "Type" ).FirstOrDefault ( ) ), e.Elements ( "Options" ).Any ( ) ? e.Elements ( "Options" ).Select ( o => ( object ) o.Elements ( "Option" ).Select ( n => n.Value ).First ( ) ) : null ) ) .ToList ( ); But currently this doesn't look as readable and I am not sure where I should add a new line and/or indent for readability. Any suggestions I could use to make consistent, readable linq blocks?

    Read the article

  • Using a message class static method taking in an action to wrap Try/Catch

    - by Chris Marisic
    I have a Result object that lets me pass around a List of event messages and I can check whether an action was successful or not. I've realized I've written this code in alot of places Result result; try { //Do Something ... //New result is automatically a success for not having any errors in it result = new Result(); } catch (Exception exception) { //Extension method that returns a Result from the exception result = exception.ToResult(); } if(result.Success) .... What I'm considering is replacing this usage with public static Result CatchException(Action action) { try { action(); return new Result(); } catch (Exception exception) { return exception.ToResult(); } } And then use it like var result = Result.CatchException(() => _model.Save(something)); Does anyone feel there's anything wrong with this or that I'm trading reusability for obscurity?

    Read the article

  • inserting datetimes into database using java

    - by gordatron
    Hi, I am wanting to insert a datetime into a MySql data base using Java and a prepared statement: Calendar cal = Calendar.getInstance(); PreparedStatement stmnt = db.PreparedStatement("INSERT INTO Run " + "(Time) VALUE (?) "); stmnt.setDate(1, new java.sql.Date(cal.getTime())); stmnt.executeQuery(); NOTE: thre is currently an error - cannot find symbol (java.sql.Date) line 4 here db is an instance of a sort of wrapper class that exposes what I need from java.sql - its just getting a prepared statement from my connection object here. Time (the column) is a date time in my database, and I can only see sedDate and setTime method but I want to store both - also my code does not work anyway ;-) if anyone could give me some pointers on inserting a combined date time (current time would be a great help as that's my first goal) into a MySql DB using a prepared statement I would be very grateful. Thanks

    Read the article

< Previous Page | 900 901 902 903 904 905 906 907 908 909 910 911  | Next Page >