Search Results

Search found 36179 results on 1448 pages for 'generic list'.

Page 10/1448 | < Previous Page | 6 7 8 9 10 11 12 13 14 15 16 17  | Next Page >

  • Linked list example using threads

    - by Carl_1789
    I have read the following code of using CRITICAL_SECTION when working with multiple threads to grow a linked list. what would be the main() part which uses two threads to add to linked list? #include <windows.h> typedef struct _Node { struct _Node *next; int data; } Node; typedef struct _List { Node *head; CRITICAL_SECTION critical_sec; } List; List *CreateList() { List *pList = (List*)malloc(sizeof(pList)); pList->head = NULL; InitializeCriticalSection(&pList->critical_sec); return pList; } void AddHead(List *pList, Node *node) { EnterCriticalSection(&pList->critical_sec); node->next = pList->head; pList->head = node; LeaveCriticalSection(&pList->critical_sec); } void Insert(List *pList, Node *afterNode, Node *newNode) { EnterCriticalSection(&pList->critical_sec); if (afterNode == NULL) { AddHead(pList, newNode); } else { newNode->next = afterNode->next; afterNode->next = newNode; } LeaveCriticalSection(&pList->critical_sec); } Node *Next(List *pList, Node *node) { Node* next; EnterCriticalSection(&pList->critical_sec); next = node->next; LeaveCriticalSection(&pList->critical_sec); return next; }

    Read the article

  • Implementing list position locator in C++?

    - by jfrazier
    I am writing a basic Graph API in C++ (I know libraries already exist, but I am doing it for the practice/experience). The structure is basically that of an adjacency list representation. So there are Vertex objects and Edge objects, and the Graph class contains: list<Vertex *> vertexList list<Edge *> edgeList Each Edge object has two Vertex* members representing its endpoints, and each Vertex object has a list of Edge* members representing the edges incident to the Vertex. All this is quite standard, but here is my problem. I want to be able to implement deletion of Edges and Vertices in constant time, so for example each Vertex object should have a Locator member that points to the position of its Vertex* in the vertexList. The way I first implemented this was by saving a list::iterator, as follows: vertexList.push_back(v); v->locator = --vertexList.end(); Then if I need to delete this vertex later, then rather than searching the whole vertexList for its pointer, I can call: vertexList.erase(v->locator); This works fine at first, but it seems that if enough changes (deletions) are made to the list, the iterators will become out-of-date and I get all sorts of iterator errors at runtime. This seems strange for a linked list, because it doesn't seem like you should ever need to re-allocate the remaining members of the list after deletions, but maybe the STL does this to optimize by keeping memory somewhat contiguous? In any case, I would appreciate it if anyone has any insight as to why this happens. Is there a standard way in C++ to implement a locator that will keep track of an element's position in a list without becoming obsolete? Much thanks, Jeff

    Read the article

  • how do I best create a set of list classes to match my business objects

    - by ken-forslund
    I'm a bit fuzzy on the best way to solve the problem of needing a list for each of my business objects that implements some overridden functions. Here's the setup: I have a baseObject that sets up database, and has its proper Dispose() method All my other business objects inherit from it, and if necessary, override Dispose() Some of these classes also contain arrays (lists) of other objects. So I create a class that holds a List of these. I'm aware I could just use the generic List, but that doesn't let me add extra features like Dispose() so it will loop through and clean up. So if I had objects called User, Project and Schedule, I would create UserList, ProjectList, ScheduleList. In the past, I have simply had these inherit from List< with the appropriate class named and then written the pile of common functions I wanted it to have, like Dispose(). this meant I would verify by hand, that each of these List classes had the same set of methods. Some of these classes had pretty simple versions of these methods that could have been inherited from a base list class. I could write an interface, to force me to ensure that each of my List classes has the same functions, but interfaces don't let me write common base functions that SOME of the lists might override. I had tried to write a baseObjectList that inherited from List, and then make my other Lists inherit from that, but there are issues with that (which is really why I came here). One of which was trying to use the Find() method with a predicate. I've simplified the problem down to just a discussion of Dispose() method on the list that loops through and disposes its contents, but in reality, I have several other common functions that I want all my lists to have. What's the best practice to solve this organizational matter?

    Read the article

  • How to put data from List<string []> to dataGridView

    - by Kirill
    Try to put some data from List to dataGridView, but have some problem with it. Currently have method, that return me required List - please see picture below code public List<string[]> ReadFromFileBooks() { List<string> myIdCollection = new List<string>(); List<string[]> resultColl = new List<string[]>(); if (chooise == "all") { if (File.Exists(filePath)) { using (FileStream fs = new FileStream(filePath, FileMode.Open, FileAccess.Read)) { StreamReader sr = new StreamReader(fs); string[] line = sr.ReadToEnd().Split(new string[] { Environment.NewLine }, StringSplitOptions.RemoveEmptyEntries); foreach (string l in line) { string[] result = l.Split(','); foreach (string element in result) { myIdCollection.Add(element); } resultColl.Add(new string[] { myIdCollection[0], myIdCollection[1], myIdCollection[2], myIdCollection[3] }); myIdCollection.Clear(); } sr.Close(); return resultColl; } } .... this return to me required data in requred form (like list from arrays). After this, try to move it to the dataGridView, that already have 4 columns with names (because i'm sure, that no than 4 colums required) - please see pic below Try to put data in to dataGridView using next code private void radioButtonViewAll_CheckedChanged(object sender, EventArgs e) { TxtLibrary myList = new TxtLibrary(filePathBooks); myList.chooise = "all"; //myList.ReadFromFileBooks(); DataTable table = new DataTable(); foreach (var array in myList.ReadFromFileBooks()) { table.Rows.Add(array); } dataGridViewLibrary.DataSource = table; } But as result got error - "required more rows that exist in dataGridVIew", but accordint to what I'm see (pic above) q-ty of rows (4) equal q-ty of arrays element in List (4). Try to check result by putting additional temp variables - but it's ok - please see pic below Where I'm wrong? Maybe i use dataGridView not in correct way?

    Read the article

  • Where to find a list of bad passwords?

    - by Steve Morgan
    I need to implement a 'stop list' to prevent users selecting common passwords in a new online service. Can anyone point me to such a list online anywhere? Edited: Note that I'm only trying to eliminate the most common passwords, not an exhaustive dictionary. And, of course, this complements a reasonably strong password policy (length, use of non-alpha characters, etc.) Thanks.

    Read the article

  • jquery Ajax sortable list stops being sortable when Ajax call updates the list html

    - by Trevor
    Hi, I am using jquery 1.4.2 and trying to achieve the following: 1 - function call that sends a value to a php page to add/remove an item 2 - returns html list of the items 3 - list should still be sortable 4 - save (serialise list) onclick My full WIP is located here [http://www.chittak.co.uk/test4/index_nw3.php][1] I tried to delegate from the level above the UL but I could get this to work $("#construnctionstage").delegate('ul li', 'click', function(){ The initial list is sortable, when you click add/remove the ajax function returns a new list with the a number of items, BUT I am doing something wrong as the alert message continues to work while the list is no longer sortable. $(document).ready(function(){ $('ul').delegate('li', 'click', function(){ alert('You clicked on an li element!'); /*$("#test-list").sortable({ handle : '.handle', update : function () { var order = $('#test-list').sortable('serialize'); $("#info").load("process-sortable.php?"+order); } });*/ }).sortable({ handle : '.handle', update : function () { var order = $('#test-list').sortable('serialize'); $("#info").load("process-sortable.php?"+order); } }); }); <div id="construnctionstage"> <ul id="test-list"> <li id="listItem_1">

    Read the article

  • Casting a non-generic type to a generic one

    - by John Sheehan
    I've got this class: class Foo { public string Name { get; set; } } And this class class Foo<T> : Foo { public T Data { get; set; } } Here's what I want to do: public Foo<T> GetSome() { Foo foo = GetFoo(); Foo<T> foot = (Foo<T>)foo; foot.Data = GetData<T>(); return foot; } What's the easiest way to convert Foo to Foo<T>? I can't cast directly InvalidCastException) and I don't want to copy each property manually (in my actual use case, there's more than one property) if I don't have to. Is a user-defined type conversion the way to go?

    Read the article

  • Passing a non-iterable to list.extend ()

    - by JS
    Hello, I am creating a public method to allow callers to write values to a device, call it write_vals() for example. Since these values will by typed live, I would like to simplify the user's life by allowing them type in either a list or a single value, depending on how many values they need to write. For example: write_to_device([1,2,3]) or write_to_device(1) My function would like to work with a flat list, so I tried to be clever and code something like this: input_list = [] input_list.extend( input_val ) This works swimmingly when the user inputs a list, but fails miserably when the user inputs a single integer: TypeError: 'int' object is not iterable Using list.append() would create a nested list when a list was passed in, which would be an additional hassle to flatten. Checking the type of the object passed in seems clumsy and non-pythonic and wishing that list.extend() would accept non-iterables has gotten me nowhere. So has trying a variety of other coding methods. Suggestions (coding-related only, please) would be greatly appreciated.

    Read the article

  • django generic view update/create: update works but create raises IntegrityError

    - by smarber
    I'm using CreateView and UpdateView directely into urls.py of my application whose name is dydict. In the file forms.py I'm using ModelForm and I'm exluding a couple of fields from being shown, some of which sould be set when either creating or updating. So, as mentioned in the title, update part works but create part doesn't which is obvious because required fields that I have exluded are sent empty which is not allowed in my case. So the question here is, how should I do to fill exluded fields into the file forms.py so that I don't have to override CreateView? Thanks in advance.

    Read the article

  • c# inheriting generic collection and serialization...

    - by Stecy
    Hi, The setup: class Item { private int _value; public Item() { _value = 0; } public int Value { get { return _value; } set { _value = value; } } } class ItemCollection : Collection<Item> { private string _name; public ItemCollection() { _name = string.Empty; } public string Name { get {return _name;} set {_name = value;} } } Now, trying to serialize using the following code fragment: ItemCollection items = new ItemCollection(); ... XmlSerializer serializer = new XmlSerializer(typeof(ItemCollection)); using (FileStream f = File.Create(fileName)) serializer.Serialize(f, items); Upon looking at the resulting XML I see that the ItemCollection.Name value is not there! I think what may be happening is that the serializer sees the ItemCollection type as a simple Collection thus ignoring any other added properties... Is there anyone having encountered such a problem and found a solution? Regards, Stécy

    Read the article

  • How to combine elements of a list

    - by Addie
    I'm working in c#. I have a sorted List of structures. The structure has a DateTime object which stores month and year and an integer which stores a value. The list is sorted by date. I need to traverse the list and combine it so that I only have one instance of the structure per date. For example: My initial list would look like this: { (Apr10, 3), (Apr10, 2), (Apr10, -3), (May10, 1), (May10, 1), (May10, -3), (Jun10, 3) } The resulting list should look like this: { (Apr10, 2), (May10, -1), (Jun10, 3) } I'm looking for a simple / efficient solution. The struct is: class CurrentTrade { public DateTime date; public int dwBuy; } The list is: private List<CurrentTrade> FillList

    Read the article

  • Converting a list of an Structure into datatable

    - by strakastroukas
    I saw a lot of examples regarding conversion of a list to data-table. I would like to convert a list of structure into a data-table. How can i do that? My structure is like ... Structure MainStruct Dim Ans1 As String Dim Ans2 As String Dim Ans3 As String Dim Skipped As Boolean End Structure and... Dim St As New MainStruct Dim Build As New List(Of MainStruct) I would like to convert the Build to a datatable

    Read the article

  • Explicitly instantiating a generic member function of a generic structure

    - by Dennis Zickefoose
    I have a structure with a template parameter, Stream. Within that structure, there is a function with its own template parameter, Type. If I try to force a specific instance of the function to be generated and called, it works fine, if I am in a context where the exact type of the structure is known. If not, I get a compile error. This feels like a situation where I'm missing a typename, but there are no nested types. I suspect I'm missing something fundamental, but I've been staring at this code for so long all I see are redheads, and frankly writing code that uses templates has never been my forte. The following is the simplest example I could come up with that illustrates the issue. #include <iostream> template<typename Stream> struct Printer { Stream& str; Printer(Stream& str_) : str(str_) { } template<typename Type> Stream& Exec(const Type& t) { return str << t << std::endl; } }; template<typename Stream, typename Type> void Test1(Stream& str, const Type& t) { Printer<Stream> out = Printer<Stream>(str); /****** vvv This is the line the compiler doesn't like vvv ******/ out.Exec<bool>(t); /****** ^^^ That is the line the compiler doesn't like ^^^ ******/ } template<typename Type> void Test2(const Type& t) { Printer<std::ostream> out = Printer<std::ostream>(std::cout); out.Exec<bool>(t); } template<typename Stream, typename Type> void Test3(Stream& str, const Type& t) { Printer<Stream> out = Printer<Stream>(str); out.Exec(t); } int main() { Test2(5); Test3(std::cout, 5); return 0; } As it is written, gcc-4.4 gives the following: test.cpp: In function 'void Test1(Stream&, const Type&)': test.cpp:22: error: expected primary-expression before 'bool' test.cpp:22: error: expected ';' before 'bool' Test2 and Test3 both compile cleanly, and if I comment out Test1 the program executes, and I get "1 5" as I expect. So it looks like there's nothing wrong with the idea of what I want to do, but I've botched something in the implementation. If anybody could shed some light on what I'm overlooking, it would be greatly appreciated.

    Read the article

  • generic identifier

    - by Werner
    Hi, as I probably do not describe the problem in the right terms, I was not able to get an answer with google. Please excuse! In the following code, I would like to replace 'hardcoded' identifier COMMENT with the variable editedField. How to do that? var editedField:String = event.dataField; if (model.multipleProcessingData[i][editedInformationProductNO].COMMENT != null{ ... }

    Read the article

  • C# method generic params parameter bug?

    - by Mike M
    Hey, I appears to me as though there is a bug/inconsistency in the C# compiler. This works fine (first method gets called): public void SomeMethod(string message, object data); public void SomeMethod(string message, params object[] data); // .... SomeMethod("woohoo", item); Yet this causes "The call is ambiguous between the following methods" error: public void SomeMethod(string message, T data); public void SomeMethod(string message, params T[] data); // .... SomeMethod("woohoo", (T)item); I could just use the dump the first method entirely, but since this is a very performance sensitive library and the first method will be used about 75% of the time, I would rather not always wrap things in an array and instantiate an iterator to go over a foreach if there is only one item. Splitting into different named methods would be messy at best IMO. Thoughts?

    Read the article

  • C# Calling Methods in Generic Classes

    - by aip.cd.aish
    I am extending the ImageBox control from EmguCV. The control's Image property can be set to anything implementing the IImage interface. All of the following implement this interface: Image<Bgr, Byte> Image<Ycc, Byte> Image<Hsv, Byte> Now I want to call the Draw method on the object of the above type (what ever it may be). The problem is when I access the Image property, the return type is IImage. IImage does not implement the Draw method, but all of the above do. I believe I can cast the object of type IImage to one of the above (the right one) and I can access the Draw method. But how do I know what the right one is? If you have a better way of doing this, please suggest that as well.

    Read the article

  • Iterator for second to last element in a list

    - by BSchlinker
    I currently have the following for loop: for(list<string>::iterator jt=it->begin(); jt!=it->end()-1; jt++) I have a list of strings which is in a larger list (list<list<string> >). I want to loop through the contents of the innerlist until I get to the 2nd to last element. This is because I have already processed the contents of the final element, and have no reason to process them again. However, using it->end()-1 is invalid -- I cannot use the - operator here. While I could use the -- operator, this would decrement this final iterator on each cycle. I believe a STL list is a doubly linked list, so from my perspective, it should be possible to do this. Advice? Thanks in advance

    Read the article

  • c# Generic overloaded method dispatching ambiguous

    - by sebgod
    Hello, I just hit a situation where a method dispatch was ambiguous and wondered if anyone could explain on what basis the compiler (.NET 4.0.30319) chooses what overload to call interface IfaceA { } interface IfaceB<T> { void Add(IfaceA a); T Add(T t); } class ConcreteA : IfaceA { } class abstract BaseClassB<T> : IfaceB<T> { public virtual T Add(T t) { ... } public virtual void Add(IfaceA a) { ... } } class ConcreteB : BaseClassB<IfaceA> { // does not override one of the relevant methods } void code() { var concreteB = new ConcreteB(); // it will call void Add(IfaceA a) concreteB.Add(new ConcreteA()); } In any case, why does the compiler not warn me or even why does it compile? Thank you very much for any answers.

    Read the article

  • Cannot inherit from generic base class and specific interface using same type with generic constrain

    - by simendsjo
    Sorry about the strange title. I really have no idea how to express it any better... I get an error on the following snippet. I use the class Dummy everywhere. Doesn't the compiler understand the constraint I've added on DummyImplBase? Is this a compiler bug as it works if I use Dummy directly instead of setting it as a constraint? Error 1 'ConsoleApplication53.DummyImplBase' does not implement interface member 'ConsoleApplication53.IRequired.RequiredMethod()'. 'ConsoleApplication53.RequiredBase.RequiredMethod()' cannot implement 'ConsoleApplication53.IRequired.RequiredMethod()' because it does not have the matching return type of 'ConsoleApplication53.Dummy'. C:\Documents and Settings\simen\My Documents\Visual Studio 2008\Projects\ConsoleApplication53\ConsoleApplication53\Program.cs 37 27 ConsoleApplication53 public class Dummy { } public interface IRequired<T> { T RequiredMethod(); } public interface IDummyRequired : IRequired<Dummy> { void OtherMethod(); } public class RequiredBase<T> : IRequired<T> { public T RequiredMethod() { return default(T); } } public abstract class DummyImplBase<T> : RequiredBase<T>, IDummyRequired where T: Dummy { public void OtherMethod() { } }

    Read the article

  • Query a List of List of Items in LINQ c#

    - by call me Steve
    I am a bit new to LINQ, here is my problem. I have a List of List of Items I like to get the Items which are present in only one List (and if I could get the List in which they are without re-iterating through the "list of list" that would be great). I am trying without success to use the Aggregate / Except / Group keywords in the Linq query but nothing close to a solution so far.

    Read the article

  • Generic TypeIdenitifier convertion.How?

    - by John
    How do I convert the TypeIdenitifier to a class type? I need to use implicit convertion. type TMyChildArray<T>=class(TMyArray<T>) private FData:Array of T; procedure AddEnd(); end; TTypeIdenitifierParentClass=class(TAnotherParentClass) protected TestField:Cardinal; end; procedure TMyChildArray<T>.AddEnd(); var elem:T; begin for elem in Fdata do TTypeIdenitifierParentClass(elem).TestField:=0; end; I get "Invalid typecast" on the implicit convertion "TTypeIdenitifierParentClass(elem).TestField:=0;". The principle I want to use is that the TypeIdenitifier will represent a class that descends from TTypeIdenitifierParentClass.There are many class types,but all of them descend that class. How do I do this?

    Read the article

  • how to create property of type generic class?

    - by Anish
    public class SelectionList<T> : ObservableCollection<SelectionItem<T>> where T : IComparable<T> { // Code } public class SelectionItem<T> : INotifyPropertyChanged { // Code } I need to create a property which is of the type SelectionList...as follows: public SelectionList<string> Sports { get; set; }. But when I replace string with DataRowView, as public SelectionList<DataRowView> Sports { get; set; }. I am getting error. Please help

    Read the article

  • Merge object from list by comparing one value

    - by Bala
    I have two List of Objects (one is master list and other is error list) and if there is a match of one value when compared two lists then merge all other error list values into mast list value (only one object). Other than iterating is there any other way to compare a value and then merge that object. Object is a Value object with some setters and getters. Appreciate your help. List<OrderVO> masterList; List<OrderVO> errorList; If errorList.OrderVO.getOrderID = masterList.OrderVO.getOrderID then masterList.OrderVO.merge(errorList.OrderVO) or copy all values of masterList.OrderVO.copy(errorList.OrderVO). Hoper this is clear

    Read the article

< Previous Page | 6 7 8 9 10 11 12 13 14 15 16 17  | Next Page >