Search Results

Search found 21759 results on 871 pages for 'int'.

Page 187/871 | < Previous Page | 183 184 185 186 187 188 189 190 191 192 193 194  | Next Page >

  • Automatically selecting and creating class objects

    - by Omin
    Lets say that we have a box class: class Box { private int width; private int height; //Box Constructor public Box( int height ) { this.height = height; width = 450; } } and a series of Box objects in our main: Box Box1 = new Box(147); Box Box2 = new Box(178); Box Box3 = new Box(784); Is there a way to use a "for" loop to go through these objects? Also, how would you make the computer create class objects for us? eg. create 10 objects using: for( int i=0; i>10; i++) { //method }

    Read the article

  • C++ MACRO that will execute a block of code and a certain command after that block.

    - by Poni
    void main() { int xyz = 123; // original value { // code block starts xyz++; if(xyz < 1000) xyz = 1; } // code block ends int original_value = xyz; // should be 123 } void main() { int xyz = 123; // original value MACRO_NAME(xyz = 123) // the macro takes the code code that should be executed at the end of the block. { // code block starts xyz++; if(xyz < 1000) xyz = 1; } // code block ends << how to make the macro execute the "xyz = 123" statement? int original_value = xyz; // should be 123 } Only the first main() works. I think the comments explain the issue. It doesn't need to be a macro but to me it just sounds like a classical "macro-needed" case. By the way, there's the BOOST_FOREACH macro/library and I think it does the exact same thing I'm trying to achieve but it's too complex for me to find the essence of what I need. From its introductory manual page, an example: #include <string> #include <iostream> #include <boost/foreach.hpp> int main() { std::string hello( "Hello, world!" ); BOOST_FOREACH( char ch, hello ) { std::cout << ch; } return 0; }

    Read the article

  • Why boost::recursive_mutex is not working as expected?

    - by Kjir
    I have a custom class that uses boost mutexes and locks like this (only relevant parts): template<class T> class FFTBuf { public: FFTBuf(); [...] void lock(); void unlock(); private: T *_dst; int _siglen; int _processed_sums; int _expected_sums; int _assigned_sources; bool _written; boost::recursive_mutex _mut; boost::unique_lock<boost::recursive_mutex> _lock; }; template<class T> FFTBuf<T>::FFTBuf() : _dst(NULL), _siglen(0), _expected_sums(1), _processed_sums(0), _assigned_sources(0), _written(false), _lock(_mut, boost::defer_lock_t()) { } template<class T> void FFTBuf<T>::lock() { std::cerr << "Locking" << std::endl; _lock.lock(); std::cerr << "Locked" << std::endl; } template<class T> void FFTBuf<T>::unlock() { std::cerr << "Unlocking" << std::endl; _lock.unlock(); } If I try to lock more than once the object from the same thread, I get an exception (lock_error): #include "fft_buf.hpp" int main( void ) { FFTBuf<int> b( 256 ); b.lock(); b.lock(); b.unlock(); b.unlock(); return 0; } This is the output: sb@dex $ ./src/test Locking Locked Locking terminate called after throwing an instance of 'boost::lock_error' what(): boost::lock_error zsh: abort ./src/test Why is this happening? Am I understanding some concept incorrectly?

    Read the article

  • SQL problem - select accross multiple tables (user groups)

    - by morpheous
    I have a db schema which looks something like this: create table user (id int, name varchar(32)); create table group (id int, name varchar(32)); create table group_member (foobar_id int, user_id int, flag int); I want to write a query that allows me to so the following: Given a valid user id (UID), fetch the ids of all users that are in the same group as the specified user id (UID) AND have group_member.flag=3. Rather than just have the SQL. I want to learn how to think like a Db programmer. As a coder, SQL is my weakest link (since I am far more comfortable with imperative languages than declarative ones) - but I want to change that. Anyway here are the steps I have identified as necessary to break down the task. I would be grateful if some SQL guru can demonstrate the simple SQL statements - i.e. atomic SQL statements, one for each of the identified subtasks below, and then finally, how I can combine those statements to make the ONE statement that implements the required functionality. Here goes (assume specified user_id [UID] = 1): //Subtask #1. Fetch list of all groups of which I am a member Select group.id from user inner join group_member where user.id=group_member.user_id and user.id=1 //Subtask #2 Fetch a list of all members who are members of the groups I am a member of (i.e. groups in subtask #1) Not sure about this ... select user.id from user, group_member gm1, group_member gm2, ... [Stuck] //Subtask #3 Get list of users that satisfy criteria group_member.flag=3 Select user.id from user inner join group_member where user.id=group_member.user_id and user.id=1 and group_member.flag=3 Once I have the SQL for subtask2, I'd then like to see how the complete SQL statement is built from these subtasks (you dont have to use the SQL in the subtask, it just a way of explaining the steps involved - also, my SQL may be incorrect/inefficient, if so, please feel free to correct it, and point out what was wrong with it). Thanks

    Read the article

  • How to handle null {id} on route?

    - by MattSlay
    What if a user hits my site with http://www.mysite.com/Quote/Edit rather than http://www.mysite.com/Quote/Edit/1000 In other words, they do not specify a value for {id}. If they do not, I want to display a nice "Not Found" page, since they did not give an ID. I currentl handle this by accepting a nullable int as the parameter in the Controller Action and it works fine. However, I'm curious if there a more standard MVC framework way of handling this, rather than the code I presently use (see below). Is a smoother way to handle this, or is this pretty mush the right way to do it? [HttpGet] public ActionResult Edit(int? id) { if (id == null) return View("QuoteNotFound"); int quoteId = (int)id; var viewModel = new QuoteViewModel(this.UserId); viewModel.LoadQuote(quoteId); if (viewModel.QuoteNo > 0) { return View("Create", viewModel.Quote.Entity); } else return View("QuoteNotFound"); }

    Read the article

  • How to create relationship mapping via Entity framework

    - by James
    I have following domain model: User { int Id; } City { int Id; } UserCity { int UserId, int CityId, dateTime StartDate } In the function where I have to attach a user to a city, the following code is working for me: UserCity uc = new UserCity(); //This is a db hit uc.User = MyEntityFrameworkDBContext.User.FirstOrDefault(u => u.ID == currentUserId); //this is a db hit uc.City = MyEntityFrameworkDBContext.City.FirstOrDefault(c => c.ID == currentCityId); uc.StartDate = userCityStartDate; //this is a db hit MyEntityFrameworkDBContext.SaveChanges(); Is there any way I can create relationships with just one single DB hit? The first two db hits are not required, actually.

    Read the article

  • Qt, can't display child widget

    - by Blin
    I have two widgets defined as follows class mainWindow : public QWidget { Q_OBJECT public: mainWindow(); void readConfig(); private: SWindow *config; QVector <QString> filePath; QVector <QLabel*> alias,procStatus; QVector <int> delay; QGridLayout *mainLayout; QVector<QPushButton*> stopButton,restartButton; QVector<QProcess*> proc; QSignalMapper *stateSignalMapper, *stopSignalMapper, *restartSignalMapper; public slots: void openSettings(); void startRunning(); void statusChange(int); void stopProc(int); void restartProc(int); void renew(); }; class SWindow : public QWidget { Q_OBJECT public: SWindow(QWidget *parent=0); void readConfig(); void addLine(int); private: QVector<QPushButton*> selectButton; QVector<QLabel*> filePath; QVector<QLineEdit*> alias; QSignalMapper *selectSignalMapper; QVector<QSpinBox*> delay; QGridLayout *mainLayout; public slots: void selectFile(int); void saveFile(); void addLineSlot(); }; when i create and display SWindow object from mainWindow like this void mainWindow::openSettings() { config = new SWindow(); config->show(); } everything is ok, but now i need to access the mainWindow from SWindow, and void mainWindow::openSettings() { config = new SWindow(this); config->show(); } doesn't display SWindow. How can i display SWindow? How do i call a function on widget close?

    Read the article

  • Get Multiple Values From Database ASP.NET/C#

    - by user1043177
    I am trying to get/return multiple values from an SQL-Server database using and display them on an ASP.NET page. I am using a stored procedure to perform the SELECT command on the Database side. I am able to return the first value that matches the variable @PERSON but only one row is returned each time. Any help would be much appreciated. Database handler class public MainSQL() { _productConn = new SqlConnection(); _productConnectionString += "data source=mssql.database.co.uk;InitialCatalog=test_data;User ID=username;Password=password"; _productConn.ConnectionString = _productConnectionString; } public string GetItemName(int PersonID) { string returnvalue = string.Empty; SqlCommand myCommand = new SqlCommand("GetItem", _productConn); myCommand.CommandType = CommandType.StoredProcedure; myCommand.Parameters.Add(new SqlParameter("@PERSON", SqlDbType.Int)); myCommand.Parameters[0].Value = PersonID; _productConn.Open(); returnvalue = (string)myCommand.ExecuteScalar(); _productConn.Close(); return (string)returnvalue; } Stored Procedure USE [test_data] GO SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO ALTER PROCEDURE [ppir].[GetItem] ( @PERSON int ) AS /*SET NOCOUNT ON;*/ SELECT Description FROM [Items] WHERE PersonID = @PERSON RETURN return.aspx namespace test { public partial class Final_Page : System.Web.UI.Page { MainSQL GetInfo; protected void Page_Load(object sender, EventArgs e) { int PersonId = (int)Session["PersonID"]; GetInfo = new MainSQL(); string itemname = GetInfo.GetItemName(PersonId); ReturnItemName.Text = itemname; } // End Page_Load } // End Class } // End Namespace

    Read the article

  • .NET port with Java's Map, Set, HashMap

    - by Nikos Baxevanis
    I am porting Java code in .NET and I am stuck in the following lines that (behave unexpectedly in .NET). Java: Map<Set<State>, Set<State>> sets = new HashMap<Set<State>, Set<State>>(); Set<State> p = new HashSet<State>(); if (!sets.containsKey(p)) { ... } The equivalent .NET code could possibly be: IDictionary<HashSet<State>, HashSet<State>> sets = new Dictionary<HashSet<State>, HashSet<State>>(); HashSet<State> p = new HashSet<State>(); if (!sets.containsKey(p)) { /* (Add to a list). Always get here in .NET (??) */ } However the code comparison fails, the program think that "sets" never contain Key "p" and eventually results in OutOfMemoryException. Perhaps I am missing something, object equality and identity might be different between Java and .NET. I tried implementing IComparable and IEquatable in class State but the results were the same. Edit: What the code does is: If the sets does not contain key "p" (which is a HashSet) it is going to add "p" at the end of a LinkedList. The State class (Java) is a simple class defined as: public class State implements Comparable<State> { boolean accept; Set<Transition> transitions; int number; int id; static int next_id; public State() { resetTransitions(); id = next_id++; } // ... public int compareTo(State s) { return s.id - id; } public boolean equals(Object obj) { return super.equals(obj); } public int hashCode() { return super.hashCode(); }

    Read the article

  • Multithreaded Win32 GUI message loop

    - by Dave18
    When do you need to use this type of modified message loop in multithreaded application? DWORD nWaitCount; HANDLE hWaitArray[4]; BOOL quit; int exitCode; while (!quit) { MSG msg; int rc; rc = MsgWaitForMultipleObjects(nWaitCount, hWaitArray, FALSE, INFINITE,QS_ALLINPUT); if (rc == WAIT_OBJECT_O + nWaitCount) { while (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE)) { if (msg.message == WM_QUIT) { quit = TRUE; exitCode = msg.wParam; break; } TranslateMessage(&msg); DispatchMessage(&msg); } } else if (rc >= WAIT_OBJECT_0 && rc < WAIT_OBJECT_0 + nwaitCount) { int nlndex = rc - WAIT_OBJECT_0; } else if (rc >= WAIT_ABANDONED_0 && rc < WAIT_ABANDONED_0+ nWaitCount) { int nlndex = rc - WAIT_ABANDONED_O; } }

    Read the article

  • SQL query: Last but one rank for user

    - by Derk
    My table structure looks like this: create table rankings ( id IDENTITY NOT NULL, user_id INT NOT NULL, game_poule_id INT NOT NULL, rank INT NOT NULL, insertDate DATETIME NOT NULL, FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE, FOREIGN KEY (game_poule_id) REFERENCES game_poules(id) ON DELETE CASCADE ); All old rankings of users per game are saved in this table. Now I want to have the last but one rank in the table for all users in a gamepoule. Has someone an idea how to achive this? Thanks

    Read the article

  • Default for generic type?

    - by Mark
    Is it possible to do something like public class PriorityQueue<TValue, TPriority=int> where TPriority : IComparable (note the =int) ? Before you suggest it, yes, I know I can just add another line: public class PriorityQueue<TValue> : PriorityQueue<TValue, int> { } But I'm wondering if it's possible to do it as a param.

    Read the article

  • C++: Binding to a base class

    - by Helltone
    The following code works, but I'm not sure it is correct/portable. #include <iostream> #include <tr1/functional> class base { public: base(int v) : x(v) {} protected: int x; }; class derived : public base { public: bool test() { return (x == 42); } }; int main(int argc, char* argv[]) { base b(42); if(std::tr1::bind((bool (base::*)()) &derived::test, b)()) { std::cout << "ok\n"; } return 0; }

    Read the article

  • please give me a solution

    - by user327832
    here is the code i have written so far but ended up giving me error import java.io.File; import java.io.FileInputStream; import java.io.IOException; import java.io.InputStream; public class Main { public static void main(String[] args) throws Exception { File file = new File("c:\\filea.txt"); InputStream is = new FileInputStream(file); long length = file.length(); System.out.println (length); bytes[] bytes = new bytes[(int) length]; try { int offset = 0; int numRead = 0; while (numRead >= 0) { numRead = is.read(bytes); } } catch (IOException e) { System.out.println ("Could not completely read file " + file.getName()); } is.close(); Object[] see = new Object[(int) length]; see[1] = bytes; System.out.println ((String[])see[1]); } }

    Read the article

  • Static member function pointer to hold non static member function

    - by user1425406
    This has defeated me. I want to have a static class variable which is a pointer to a (non-static) member function. I've tried all sorts of ways, but with no luck (including using typedefs, which just seemed to give me a different set of errors). In the code below I have the static class function pointer funcptr, and I can call it successfully from outside the class, but not from within the member function CallFuncptr - which is what I want to do. Any suggestions? #include <stdio.h> class A { public: static int (A::*funcptr)(); int Four() { return 4;}; int CallFuncptr() { return (this->*funcptr)(); } // doesn't link - undefined reference to `A::funcptr' }; int (A::*funcptr)() = &A::Four; int main() { A fred; printf("four? %d\n", (fred.*funcptr)()); // This works printf("four? %d\n", fred.CallFuncptr()); // But this is the way I want to call it }

    Read the article

  • c++ templates and inheritance

    - by Armen Ablak
    Hey, I'm experiencing some problems with breaking my code to reusable parts using templates and inheritance. I'd like to achieve that my tree class and avltree class use the same node class and that avltree class inherits some methods from the tree class and adds some specific ones. So I came up with the code below. Compiler throws an error in tree.h as marked below and I don't really know how to overcome this. Any help appreciated! :) node.h: #ifndef NODE_H #define NODE_H #include "tree.h" template <class T> class node { T data; ... node() ... friend class tree<T>; }; #endif tree.h #ifndef DREVO_H #define DREVO_H #include "node.h" template <class T> class tree { public: //signatures tree(); ... void insert(const T&); private: node<T> *root; //missing type specifier - int assumed. Note: C++ does not support default-int }; //implementations #endif avl.h #ifndef AVL_H #define AVL_H #include "tree.h" #include "node.h" template <class T> class avl: public tree<T> { public: //specific int findMin() const; ... protected: void rotateLeft(node<T> *)const; private: node<T> *root; }; #endif avl.cpp (I tried separating headers from implementation, it worked before I started to combine avl code with tree code) #include "drevo" #include "avl.h" #include "vozlisce.h" template class avl<int>; //I know that only avl with int can be used like this, but currently this is doesn't matter :) //implementations ...

    Read the article

  • Why is the compiler not complaining about an additional ',' in Array or Object Initializers?

    - by Danvil
    Using simple type like class A { public int X, Y; } with object intializers, one can write var a = new A { X=0, Y=0 }; But the following is also accepted by the compiler: var a = new A { X=0, Y=0, }; // notice the additional ',' Same for int[] v = new int[] { 1, 2, }; This looks a bit strange ... Did they forgot to reject the additional ',' in the compiler or is there a deeper meaning behind this?

    Read the article

  • What is a recommended Android utility class collection?

    - by Sebastian Roth
    I often find myself writing very similar code across projects. And more often than not, I copy stuff over from old projects. Things like: Create images with round corners read density into a static variable & re-use. 4 lines.. disable / hide multiple views / remote views at once. Example: } public static void disableViews(RemoteViews views, int... ids) { for (int id : ids) { views.setInt(id, SET_VISIBILITY, View.GONE); } } public static void showViews(RemoteViews views, int... ids) { for (int id : ids) { views.setInt(id, SET_VISIBILITY, View.VISIBLE); } } I'd love to package these kind of functions into 1 letter / 2 letter class names, i.e. V.showViews(RemoteViews views, int... ids) would be easy to write & remember I hope. I'm searching for Github recommendations, links and if nothing is found, I perhaps will start a small project on github to collect.

    Read the article

  • C#: how to construct strings

    - by Craig Johnston
    Which of these will achieve the correct result: (1) int X = 23; string str = "HELLO" + X.ToString() + "WORLD"; (2) int X = 23; string str = "HELLO" + X + "WORLD"; (3) int X = 23; string str = "HELLO" + (string)X + "WORLD"; EDIT: The 'correct' result is to output: HELLO23WORLD

    Read the article

  • Multiple column sorting (SQL SERVER 2005)

    - by Newbie
    I have a table which looks like Col1 col2 col3 col4 col5 1 5 1 4 6 1 4 0 3 7 0 1 5 6 3 1 8 2 1 5 4 3 2 1 4 The script is declare @t table(col1 int, col2 int, col3 int,col4 int,col5 int) insert into @t select 1,5,1,4,6 union all select 1,4,0,3,7 union all select 0,1,5,6,3 union all select 1,8,2,1,5 union all select 4,3,2,1,4 I want the output to be every column being sorted in ascending order i.e. Col1 col2 col3 col4 col5 0 1 0 1 3 1 3 1 1 4 1 4 2 3 5 1 5 2 4 6 4 8 5 6 7 I already solved tye problem by the folowing program Select x1.col1 ,x2.col2 ,x3.col3 ,x4.col4 ,x5.col5 From (Select Row_Number() Over(Order By col1) rn1, col1 From @t)x1 Join(Select Row_Number() Over(Order By col2) rn2, col2 From @t)x2 On x1.rn1=x2.rn2 Join(Select Row_Number() Over(Order By col3) rn3, col3 From @t)x3 On x1.rn1=x3.rn3 Join(Select Row_Number() Over(Order By col4) rn4, col4 From @t)x4 On x1.rn1=x4.rn4 Join(Select Row_Number() Over(Order By col5) rn5, col5 From @t)x5 On x1.rn1=x5.rn5 But I am not happy with this solution. Is there any better way to achieve the same? (Using set based approach) If so, could any one please show an example. Thanks

    Read the article

  • Getting the full-name of the current user, returns an empty string (C#/C++)

    - by Nir
    I try to get the full-name of the current log-in user (Fullname, not username). The following code C#, C++ works fine but on XP computers not connected to the Net, I get empty string as result if I run it ~20 minutes after login (It runs OK whithin the first ~20 minutes after login) A Win32 API (GetUserNameEx) is used rather that PrincipalContext since it PrincipalContext may takes up to 15 seconds when working offline. Any Help why am I getting an empty string as result though a user full name is specified??? - C# Code public static string CurrentUserFullName { get { const int EXTENDED_NAME_FORMAT_NAME_DISPLAY = 3; StringBuilder userName = new StringBuilder(256); uint length = (uint) userName.Capacity; string ret; if (GetUserNameEx(EXTENDED_NAME_FORMAT_NAME_DISPLAY, userName, ref length)) { ret = userName.ToString(); } else { int errorCode = Marshal.GetLastWin32Error(); throw new Win32Exception("GetUserNameEx Failed. Error code - " + errorCode); } return ret; } } [DllImport("Secur32.dll", CharSet = CharSet.Auto, SetLastError = true)] private static extern bool GetUserNameEx(int nameFormat, StringBuilder lpNameBuffer, ref uint lpnSize); - Code in C++ #include "stdafx.h" #include <windows.h> #define SECURITY_WIN32 #include <Security.h> #pragma comment( lib, "Secur32.lib" ) int _tmain(int argc, _TCHAR* argv[]) { char szName[100]; ULONG nChars = sizeof( szName ); if ( GetUserNameEx( NameDisplay, szName, &nChars ) ) { printf( "Name: %s\n", szName); } else { printf( "Failed to GetUserNameEx\n" ); printf( "%d\n", GetLastError() ); } return 0; }

    Read the article

  • C++ RPC library suggestions

    - by Oxsnarder
    I'm looking for suggestions regarding RPC libraries implemented in C++, for C++ developers. Some requirements constraints: Should work on both linux/unix and win32 systems Be able to execute free function and class methods Hopefully written in modern C++ not 90's/java-esque C++ Be able to function over networks and hetrogenous architectures Not too slow or inefficient Hopefully provide interfaces for TR1 style std::function's et al. My example usage is to invoke the free function foo on a remote machine. ---snip--- // foo translation unit int foo(int i, int j) { return i + j; } ---snip--- ---snip--- // client side main int main() { //register foo on client and server //setup necassary connections and states int result; if (RPCmechanism.invoke("foo",4,9,result)) std::cout << "foo(4,9) = " result << std::endl; else std::cout << "failed to invoke foo(4,9)!" << std::endl; return 0; } ---snip--- Something that can achieve the above or similar would be great.

    Read the article

  • Is there a better way to throttle a high throughput job?

    - by ChaosPandion
    I created a simple class that shows what I am trying to do without any noise. Feel free to bash away at my code. That's why I posted it here. public class Throttled : IDisposable { private readonly Action work; private readonly Func<bool> stop; private readonly ManualResetEvent continueProcessing; private readonly Timer throttleTimer; private readonly int throttlePeriod; private readonly int throttleLimit; private int totalProcessed; public Throttled(Action work, Func<bool> stop, int throttlePeriod, int throttleLimit) { this.work = work; this.stop = stop; this.throttlePeriod = throttlePeriod; this.throttleLimit = throttleLimit; continueProcessing = new ManualResetEvent(true); throttleTimer = new Timer(ThrottleUpdate, null, throttlePeriod, throttlePeriod); } public void Dispose() { throttleTimer.Dispose(); ((IDisposable)continueProcessing).Dispose(); } public void Execute() { while (!stop()) { if (Interlocked.Increment(ref totalProcessed) > throttleLimit) { lock (continueProcessing) { continueProcessing.Reset(); } if (!continueProcessing.WaitOne(throttlePeriod)) { throw new TimeoutException(); } } work(); } } private void ThrottleUpdate(object state) { Interlocked.Exchange(ref totalProcessed, 0); lock (continueProcessing) { continueProcessing.Set(); } } }

    Read the article

< Previous Page | 183 184 185 186 187 188 189 190 191 192 193 194  | Next Page >