Search Results

Search found 16050 results on 642 pages for 'linq to objects'.

Page 297/642 | < Previous Page | 293 294 295 296 297 298 299 300 301 302 303 304  | Next Page >

  • Want to understand C++ sentry object

    - by Romain Hippeau
    I answered this [question][1] and somebody else had answered as he modern C++ equivalent would be a sentry object: construct it at the beginning of a function, with its constructor implementing call(), and upon return (or abnormal exit), its destructor implements I am not familiar with using sentry objects in C++. I thought they were limited to input and output streams. Could somebody explain to me about C++ sentry objects as well as how to use them as an around interceptor for one or more methods in a class ? [1]: http://stackoverflow.com/questions/2688043/call-return-feature-of-classic-cc-with-classes-what-modern-languages-have-it/2688095#2688095 /

    Read the article

  • HQL: illegal attempt to dereference collection

    - by skip
    The situation is like this: I have an entity Book that holds a one-to-many relationship with Chapter. Now if I try the query, "from Book book inner join book.chapters chapter where chapter.title like '%hibernate%'", it gives me the desired result. But if I try, "from Book where book.chapters.title like '%hibernate%'", I get the error illegal attempt to dereference collection. The thing is that I only want the collection of Book objects in return and not a collection of pair of Book and Chapter objects in return which I get with the former query. Could someone help me understand?

    Read the article

  • NSSortdescriptor, finding the path to the key I wish to use for sorting.

    - by RickiG
    Hi I am using an NSSortdescriptor to sort a collection of NSArrays, I then came across a case where the particular NSArray to be sorted contains an NSDictionary who contains an NSDictionary. I would like to sort from the string paired with a key in the last dictionary. This is how I would reference the string: NSDictionary *productDict = [MyArray objectAtIndex:index]; NSString *dealerName = [[productDict objectForKey:@"dealer"] objectForKey:@"name"]; How would I use the dealerName in my NSSortdescriptor to sort the array? NSSortDescriptor * sortDesc = [[NSSortDescriptor alloc] initWithKey:/* ? */ ascending:YES]; sortedDealerArray = [value sortedArrayUsingDescriptors:sortDesc]; [sortDesc release]; Hope someone could help me a bit with how I go about sorting according to keys inside objects inside other objects:) Thank you.

    Read the article

  • Direct flow depending on incoming dynamic type

    - by Improfane
    I have a listener class that accepts GUI change events in one method. The incoming event objects have a superclass of a type of GUI Event, the behaviour should depend on the dynamic type of the incoming variable. I wanted to do do lots of methods like: handleGUIEvent(EventChangedX event) handleGUIEvent(EventChangedY event) I am using a single event listener and receiving objects of various types but the behaviour should be different for each. What would you do? I do not want to use a switch statement as this would get unmaintainable.

    Read the article

  • How can I write this Table Valued Function as a Stored Procedure?

    - by Alex
    I have the following TVF for fulltext search: FUNCTION [dbo].[Fishes_FullTextSearch] (@searchtext nvarchar(4000), @limitcount int) RETURNS TABLE AS RETURN SELECT * FROM Fishes INNER JOIN CONTAINSTABLE(Fishes, *, @searchtext, @limitcount) AS KEY_TBL ON Fishes.Id = KEY_TBL.[KEY] When I'm using this TVF, it doesn't return a collection of objects of type Fish (which I want!) - instead LINQ creates a new result type which includes all "Fish" fields and the fields Key and Rank. In another question, it was suggested that I rewrite this TVF into a stored procedure for it to return Fish objects only. Can someone help me do this please? Also, it needs to be ordered by Rank. Thank you!

    Read the article

  • How should I build a simple database package for my python application?

    - by Carson Myers
    I'm building a database library for my application using sqlite3 as the base. I want to structure it like so: db/ __init__.py users.py blah.py etc.py So I would do this in Python: import db db.users.create('username', 'password') I'm suffering analysis paralysis (oh no!) about how to handle the database connection. I don't really want to use classes in these modules, it doesn't really seem appropriate to be able to create a bunch of "users" objects that can all manipulate the same database in the same ways -- so inheriting a connection is a no-go. Should I have one global connection to the database that all the modules use, and then put this in each module: #users.py from db_stuff import connection Or should I create a new connection for each module and keep that alive? Or should I create a new connection for every transaction? How are these database connections supposed to be used? The same goes for cursor objects: Do I create a new cursor for each transaction? Create just one for each database connection?

    Read the article

  • Many-to-one relationship in SQLAlchemy

    - by Arrieta
    This is a beginner-level question. I have a catalog of mtypes: mtype_id name 1 'mtype1' 2 'mtype2' [etc] and a catalog of Objects, which must have an associated mtype: obj_id mtype_id name 1 1 'obj1' 2 1 'obj2' 3 2 'obj3' [etc] I am trying to do this in SQLAlchemy by creating the following schemas: mtypes_table = Table('mtypes', metadata, Column('mtype_id', Integer, primary_key=True), Column('name', String(50), nullable=False, unique=True), ) objs_table = Table('objects', metadata, Column('obj_id', Integer, primary_key=True), Column('mtype_id', None, ForeignKey('mtypes.mtype_id')), Column('name', String(50), nullable=False, unique=True), ) mapper(MType, mtypes_table) mapper(MyObject, objs_table, properties={'mtype':Relationship(MType, backref='objs', cascade="all, delete-orphan")} ) When I try to add a simple element like: mtype1 = MType('mtype1') obj1 = MyObject('obj1') obj1.mtype=mtype1 session.add(obj1) I get the error: AttributeError: 'NoneType' object has no attribute 'cascade_iterator' Any ideas?

    Read the article

  • Why do Java and C# not have implicit conversions to boolean?

    - by Shaun
    Since I started Java it's been very aggravating for me that it doesn't support implicit conversions from numeric types to booleans, so you can't do things like: if (flags & 0x80) { ... } instead you have to go through this lunacy: if ((flags & 0x80) != 0) { ... } It's the same with null and objects. Every other C-like language I know including JavaScript allows it, so I thought Java was just moronic, but I've just discovered that C# is the same (at least for numbers, don't know about null/objects): http://msdn.microsoft.com/en-us/library/c8f5xwh7(VS.71).aspx Microsoft changed it on purpose from C++, so why? Clearly I'm missing something. Why change (what I thought was) the most natural thing in the world to make it longer to type? What on Earth is wrong with it?

    Read the article

  • Get/Set nested property values

    - by Daniel Deer
    I'll try to be more descriptive here. A Few Q's: using: var foo = new Foo() { Bar = new Bar() { Value = "Value" } }; var value = DataBinder.Eval(foo, "Bar.Value"); Or: This one It is possible to retrieve an internal nested property using property path syntax. Is there a way to set/trigger a nested property (a regular property not DependencyProperty) easily with some kind of simple mechanisms as described here? I want to acheive something like: string newValue = "Hello World!"; DataBinder.EvalSet(foo, "Bar.Value", NewValue); Is there any mechanism that support both property path (for nested objects) and XPATHs (if the objects are XPATH navigable of course) ? again, that supports get and set options. Thanks, DD

    Read the article

  • Teacher confused about MVC?

    - by Gideon
    I have an assignment to create a game in java using MVC as a pattern. The thing is that stuff I read about MVC aren't really what the teacher is telling me. What I read is that the Model are the information objects, they are manipulated by the controllers. So in a game the controller mutates the placement of the objects and check if there is any collision etc. What my teacher told me is that I should put everything that is universal to the platform in the models and the controllers should only tell the model which input is given. That means the game loop will be in a model class, but also collision checks etc. So what I get from his story is that the View is the screen, the Controller is the unput handeler, and the Model is the rest. Can someone point me in the right direction?

    Read the article

  • PHP array of object(stdClass) fusion/intersect?

    - by Gremo
    $arr1 is an associative array of anonymus objects: array 15898 => object(stdClass)[8] public 'date' => int $arr2 is another associative array with two (or more, it's not fixed) properties: array 15898 => object(stdClass)[10] public 'fruits' public 'drinks' I can't find any function for intersect and content fusion when dealing with objects. Basically i'd like to obtain: array 15898 => object(stdClass)[8] public 'date' => int public 'fruits' public 'drinks' Question is: is this even possible?

    Read the article

  • Xcode automatically converts the object to NSArray

    - by Farrukh Javeid
    I have been working on an app and during the development, I am facing a very strange problem. I have a NSMutableArray tempSortedArray, which is full of objects of Store types. All the objects are valid as I can see them in my GUI, the problem arises when I iterate through the array, at index 90, which can be generally anyone, the XCode converts the Store object to NSMutableArray object. Any idea, why this is happening. This is the code to check out what I am doing: NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"cashBack" ascending:NO]; NSArray *sortDescriptors = [NSArray arrayWithObject:sortDescriptor]; NSArray *sortedArray = [storesArray sortedArrayUsingDescriptors:sortDescriptors]; for (int i = 0; i < [tempSortedArray count]; i++) { Store *currentStore = [tempSortedArray objectAtIndex:i]; NSLog(@"store class: %@", [currentStore.class description]); if (currentStore.cashBackTypeString != (id)[NSNull null]) { //do whatever is required to do here }

    Read the article

  • Show a django relationship in a template

    - by kevin_82
    I have a django model as follows: class Person(models.Model): name = models.CharField(max_length=255) class Relationship(models.Model): parent = models.ForeignKey(Person) child = models.ForeignKey(Person) description = models.TextField(blank=True) In my view, I pass a certain person, and the relationships in which he/she is parent: person = Person.objects.filter(name ='some name') descendant_relationships = Relationship.objects.filter(parent = person) An I want to show this person's descendants in a list in a template: <ul> {% for item in descendant_relationships%} <li> {{item.child.name}} - {{item.description}} </li> {% endfor %} </ul> But this template code will not show the children of children (i.e. grandchildren, great-grandchildren etc.). How can I get these lower level descendants to show up? I imagine recursion is necessary somewhere, but where?

    Read the article

  • Can using non primitive Integer/ Long datatypes too frequently in the application, hurt the performance??

    - by Marcos
    I am using Long/Integer data types very frequently in my application, to build Generic datatypes. I fear that using these wrapper objects instead of primitive data types may be harmful for performance since each time it needs to create objects which is an expensive operation. but also it seems that I have no other choice(when I have to use primtives with generics) rather than just using them. However, still it would be great if you can suggest if there is anything I could do to make it better. or any way if I could just avoid it ?? Also What may be the downsides of this ? Suggestions welcomed!

    Read the article

  • Python: Access members of a set

    - by emu
    Say I have a set myset of custom objects that may be equal although their references are different (a == b and a is not b). Now if I add(a) to the set, Python correctly assumes that a in myset and b in myset even though there is only len(myset) == 1 object in the set. That is clear. But is it now possible to extract the value of a somehow out from the set, using b only? Suppose that the objects are mutable and I want to change them both, having forgotten the direct reference to a. Put differently, I am looking for the myset[b] operation, which would return exactly the member a of the set. It seems to me that the type set cannot do this (faster than iterating through all its members). If so, is there at least an effective work-around?

    Read the article

  • What would happen to GC if I run process with priority = RealTime?

    - by Bobb
    I have a C# app which runs with priority RealTime. It was all fine until I made few hectic changes in past 2 days. Now it runs out of memory in few hours. I am trying to find whether it is a memory leak I created of this is because I consume lot more objects than before and GC simply cant collect them because it runs with same priority. My question is - what could happen to GC when it tries to collect objects in application with RealTime priority (there is also at least one thread running with Highest thread priority)? (P.S. by realtime priority I mean Process.GetCurrentProcess().PriorityClass = ProcessPriorityClass.RealTime) Sorry forgot to tell. GC is in Server mode

    Read the article

  • How to deal with callback to your UIController after your UIController unloads?

    - by erotsppa
    Suppose your controller is a table view and one of the cells you are going off to do a length task (say download a thumbnail) to be viewed in the cell. Typically you would have the network call do a callback to your controller when it is done downloading. The callback can then reload the table or do some other form of UI update (hides a spinner etc). However, what if the controller is unloaded? Say the user navigated away from this controller and it got released? What happens? Will the callback still work despite the controller now not in memory? Also, if the callback operates on some objects (say the UITableView) what happens when the controller is deallocated? I suppose the controller can release all the objects and the callback would just be calling methods on nil to prevent crash. But is this the convention?

    Read the article

  • How should flushing be handled in a doctrine EntityManager instance shared across different services in symfony2?

    - by Jbm
    I have defined several services in symfony 2 which persist changes to the database. These services have the doctrine instance as one of their dependencies: a.given.service: class: Acme\TestBundle\Service\AGivenService arguments: [@doctrine] If I have two different services and both of them persist objects through the EntityManager, which is obtained like this from the doctrine instance: $em = $doctrine->getEntityManager(); Would all services always share the same EntityManager? If so, how should I handle flushing if I wanted to handle all the changes in a single transaction? I have checked this: http://docs.doctrine-project.org/projects/doctrine-orm/en/2.0.x/reference/transactions-and-concurrency.html and it explains how to handle different transactions in a request, but I want to achieve the opposite, which is having different changes in different services handled as a single transaction. Is there a better approach to handle multiple changes in different services? For now my best bet is having a front-end service in charge of calling the other services and doing the flushing afterwards. Backend services would persist objects but would not do any flushing.

    Read the article

  • Django model class and custom property

    - by dArignac
    Howdy - today a weird problem occured to me: I have a modle class in Django and added a custom property to it that shall not be saved into the database and therefore is not represent in the models structure: class Category(models.Model): groups = models.ManyToManyField(Group) title = defaultdict() Now, when I'm within the shell or writing a test and I do the following: c1 = Category.objects.create() c1.title['de'] = 'german title' print c1.title['de'] # prints "german title" c2 = Category.objects.create() print c2.title['de'] # prints "german title" <-- WTF? It seems that 'title' is kind of global. If I change title to a simple string it works as expected, so it has to do something with the dict? I also tried setting title as a property: title = property(_title) But that did not work, too. So, how can I solve this? Thank you in advance! enter code here

    Read the article

  • C# What would happen to GC if I run process with priority = RealTime?

    - by Bobb
    I have a C# app which runs with priority RealTime. It was all fine until I made few hectic changes in past 2 days. Now it runs out of memory in few hours. I am trying to find whether it is a memory leak I created of this is because I consume lot more objects than before and GC simply cant collect them because it runs with same priority. My question is - what could happen to GC when it tries to collect objects in application with RealTime priority (there is also at least one thread running with Highest thread priority)? (P.S. by realtime priority I mean Process.GetCurrentProcess().PriorityClass = ProcessPriorityClass.RealTime)

    Read the article

  • Arry of pointers in objective c using NSArray

    - by Amir
    Hello, I am writting program for my iphone and have a qestion. lets say i have class named my_obj class my_obj { NSString *name; NSinteger *id; NSinteger *foo; NSString *boo; } now i allocate 100 objects from type my_obj and insert them to array from type NSArray. then i want to sort the Array in two different ways. one by the name and the second by the id. i want to allocate another two arrays from type NSArray *arraySortByName *arraySortById what i need to do if i just want the sorted arrays to be referenced to the original array so i will get two sorted arrays that point to the original array (that didnt changed!) i other word i dont want to allocate another 100 objects to each sorted array.

    Read the article

  • Javascript: How to filter object array based on attributes?

    - by JGreig
    I have the following JavaScript JSON array of real estate home objects: var json = { 'homes' : [ { "home_id":"1", "price":"925", "sqft":"1100", "num_of_beds":"2", "num_of_baths":"2.0", }, { "home_id":"2", "price":"1425", "sqft":"1900", "num_of_beds":"4", "num_of_baths":"2.5", }, // ... (more homes) ... ]} var xmlhttp = eval('(' + json + ')'); homes = xmlhttp.homes; What I would like to do is be able to perform a filter on the object to return a subset of "home" objects. For example, I want to be able to filter based on: price, sqft, num_of_beds, and num_of_baths. Question: How can I perform something in javascript like the pseudo-code below: var newArray = homes.filter( price <= 1000 & sqft >= 500 & num_of_beds >=2 & num_of_baths >= 2.5); Note, the syntax does not have to be exactly like above. This is just an example.

    Read the article

  • C#, Generic Lists and Inheritance

    - by Andy
    I have a class called Foo that defines a list of objects of type A: class Foo { List<A> Items = new List<A>(); } I have a class called Bar that can save and load lists of objects of type B: class Bar { void Save(List<B> ComplexItems); List<B> Load(); } B is a child of A. Foo, Bar, A and B are in a library and the user can create children of any of the classes. What I would like to do is something like the following: Foo MyFoo = new Foo(); Bar MyBar = new Bar(); MyFoo.Items = MyBar.Load(); MyBar.Save(MyFoo.Items); Obviously this won't work. Is there a clever way to do this that avoids creating intermediate lists? thanks, Andy

    Read the article

  • C++ object in memory

    - by Neo_b
    Hello. Is there a standard in storing a C++ objects in memory? I wish to set a char* pointer to a certain address in memory, so that I can read certain objects' variables directly from the memory byte by byte. When I am using Dev C++, the variables are stored one by one right in the memory address of an object in the order that they were defined. Now, can it be different while using a different compiler (like the variables being in a different order, or somewhere else)? Thank you in advance. :-)

    Read the article

< Previous Page | 293 294 295 296 297 298 299 300 301 302 303 304  | Next Page >