Search Results

Search found 5259 results on 211 pages for 'interrupt handling'.

Page 52/211 | < Previous Page | 48 49 50 51 52 53 54 55 56 57 58 59  | Next Page >

  • Several client waiting for the same event

    - by ff8mania
    I'm developing a communication API to be used by a lot of generic clients to communicate with a proprietary system. This proprietary system exposes an API, and I use a particular classes to send and wait messages from this system: obviously the system alert me that a message is ready using an event. The event is named OnMessageArrived. My idea is to expose a simple SendSyncMessage(message) method that helps the user/client to simply send a message and the method returns the response. The client: using ( Communicator c = new Communicator() ) { response = c.SendSync(message); } The communicator class is done in this way: public class Communicator : IDisposable { // Proprietary system object ExternalSystem c; String currentRespone; Guid currentGUID; private readonly ManualResetEvent _manualResetEvent; private ManualResetEvent _manualResetEvent2; String systemName = "system"; String ServerName = "server"; public Communicator() { _manualResetEvent = new ManualResetEvent(false); //This methods are from the proprietary system API c = SystemInstance.CreateInstance(); c.Connect(systemName , ServerName); } private void ConnectionStarter( object data ) { c.OnMessageArrivedEvent += c_OnMessageArrivedEvent; _manualResetEvent.WaitOne(); c.OnMessageArrivedEvent-= c_OnMessageArrivedEvent; } public String SendSync( String Message ) { Thread _internalThread = new Thread(ConnectionStarter); _internalThread.Start(c); _manualResetEvent2 = new ManualResetEvent(false); String toRet; int messageID; currentGUID = Guid.NewGuid(); c.SendMessage(Message, "Request", currentGUID.ToString()); _manualResetEvent2.WaitOne(); toRet = currentRespone; return toRet; } void c_OnMessageArrivedEvent( int Id, string root, string guid, int TimeOut, out int ReturnCode ) { if ( !guid.Equals(currentGUID.ToString()) ) { _manualResetEvent2.Set(); ReturnCode = 0; return; } object newMessage; c.FetchMessage(Id, 7, out newMessage); currentRespone = newMessage.ToString(); ReturnCode = 0; _manualResetEvent2.Set(); } } I'm really noob in using waithandle, but my idea was to create an instance that sends the message and waits for an event. As soon as the event arrived, checks if the message is the one I expect (checking the unique guid), otherwise continues to wait for the next event. This because could be (and usually is in this way) a lot of clients working concurrently, and I want them to work parallel. As I implemented my stuff, at the moment if I run client 1, client 2 and client 3, client 2 starts sending message as soon as client 1 has finished, and client 3 as client 2 has finished: not what I'm trying to do. Can you help me to fix my code and get my target? Thanks!

    Read the article

  • handling the logout functionality on the iPhone

    - by Nanz
    This is the first iPhone application i am working on. To use the application, the user has to login to our server. I am done with that part. Now the problem i am facing is how to logout the user from the server, deallocate all the memory and start afresh without quitting the app. After the user logs out, i want the exact same things to happen as in applicationdidfinishlaunching method. But i dont know how to go about it. The app has a tab bar which is set up in mainWindow.xib.

    Read the article

  • Error debugging - Conversion from String to Double

    - by Jamie Taylor
    I'm doing some error debugging trying to get the errors on our website down to a minimum and there seems to be an error that is popping up quite a lot Conversion from string "" to type 'Double' is not valid. I'm unable to replicate this problem but I can see that it is happening. I've been looking through the code in one of the pages and strolled across this Dim varWeek As String If varWeek < 10 Then 'Do something' End If Could this be causing the problem as it is trying to see if a String is less than 10 which is an Integer? As I said before as I am unable to see this error in the first place so changing this to an Integer doesn't change anything on my system. Thanks.

    Read the article

  • Calling same function until it connect to server

    - by user171523
    I am in the process of designing a system where i need to keep on trying to connect to MQ server unitl i get a connection. By default if the MQ is not availlble it will thorugh exception. How can call the same method again and again until i get the connection. I know i can use recursion, is there any better way to do it . Becuase i would like to avoid infinite loops. I also want to wait the the furthere processing until i get connection. I am using .net 2.0 with C#. It is window Service application.

    Read the article

  • C#: When should I use TryParse?

    - by zxcvbnm
    I understand it doesn't throw an Exception and because of that it might be sightly faster, but also, you're most likely using it to convert input to data you can use, so I don't think it's used so often to make that much of difference in terms of performance. Anyway, the examples I saw are all along the lines of an if/else block with TryParse, the else returning an error message. And to me, that's basically the same thing as using a try/catch block with the catch returning an error message. So, am I missing something? Is there a situation when this is actually useful?

    Read the article

  • How can I make properties files mandatory in Spring?

    - by Paulo Guedes
    I have an ApplicationContext.xml file with the following node: <context:property-placeholder location="classpath:hibernate.properties, classpath:pathConfiguration.properties" /> It specifies that both properties files will be used by my application. But if one of these files does not exist, no error ir thrown. How can I throw an exception for any of these files? They should me mandatory.

    Read the article

  • How to handle different roles with different previliges in PHP?

    - by user261002
    I would like to know how we can create different "user Roles" for different users in PHP. example: Administrator can create all types of users, add, view, manipulate data, delete managers, viewers, and workers, etc managers can only create, workers and viewers, can add and view data, workers can't create new users, but can only add data and view data, viewers can only view data that has been added to the DB by workers, managers and administrators. I though its better to use different sessions like : $_SESSION['admin'] $_SESSION['manager'] $_SESSION['worker'] $_SESSION['viewvers'] and for every page check which of them have a true or yes value, but I want to know how do they do it in real and big projects??? is there any other way???

    Read the article

  • Is it possible to capture a "file not found" from another process and then return a file to that pro

    - by Neil N
    I have a legacy application that looks for files in a directory. It does not handle missing files very well. What I want to do is "capture" the file not found errors, and send another file back to the calling app instead. Similar to how you could handle a 404 error on a webserver and return something based on what the requested URL was, except on the local file system. Is this possible? And more preferably, is it possible in .Net?

    Read the article

  • How can I make properties in properties files mandatory in Spring?

    - by Paulo Guedes
    I have an ApplicationContext.xml file with the following node: <context:property-placeholder location="classpath:hibernate.properties, classpath:pathConfiguration.properties" /> It specifies that both properties files will be used by my application. Inside pathConfiguration.properties, some paths are defined, such as: PATH_ERROR=/xxx/yyy/error PATH_SUCCESS=/xxx/yyy/success A PathConfiguration bean has setters for each path. The problem is: when some of those mandatory paths are not defined, no error is thrown. How and where should I handle this problem?

    Read the article

  • Keyboard- and mouse-event transparent widget

    - by Gajender
    When i click a button my main window i want it to become transparent to keyboard and mouse events, i.e. all keyboard and mouse events should pass to any windows below it as if that window is not present there. "Qt::WA_TransparentForMouseEvents" does not work here as this only make child windows transparent to keyboard and mouse events i guess. And my window is main window and i want to pass all event to any window on desktop not just parent window.

    Read the article

  • Is it safe to silently catch ClassCastException when searching for a specific value?

    - by finnw
    Suppose I am implementing a sorted collection (simple example - a Set based on a sorted array.) Consider this (incomplete) implementation: import java.util.*; public class SortedArraySet<E> extends AbstractSet<E> { @SuppressWarnings("unchecked") public SortedArraySet(Collection<E> source, Comparator<E> comparator) { this.comparator = (Comparator<Object>) comparator; this.array = source.toArray(); Collections.sort(Arrays.asList(array), this.comparator); } @Override public boolean contains(Object key) { return Collections.binarySearch(Arrays.asList(array), key, comparator) >= 0; } private final Object[] array; private final Comparator<Object> comparator; } Now let's create a set of integers Set<Integer> s = new SortedArraySet<Integer>(Arrays.asList(1, 2, 3), null); And test whether it contains some specific values: System.out.println(s.contains(2)); System.out.println(s.contains(42)); System.out.println(s.contains("42")); The third line above will throw a ClassCastException. Not what I want. I would prefer it to return false (as HashSet does.) I can get this behaviour by catching the exception and returning false: @Override public boolean contains(Object key) { try { return Collections.binarySearch(Arrays.asList(array), key, comparator) >= 0; } catch (ClassCastException e) { return false; } } Assuming the source collection is correctly typed, what could go wrong if I do this?

    Read the article

  • Asp.net error object not set to a reference

    - by Frank
    Hi all, Because I rush in development (a lot of whip cracking here) and declare my objects at the top of the function and instantiate inside my try-catch block, I get a lot of the good old "object not set to an instance of an object" errors while doing TDD, and later if I do miss a branch that object was used in (doing VB now, would prefer C#) or just in every day coding, object not set to an instance of an object is a bit vague. Sure the stack trace sends me to the line the error occured at, but it would be nice if I could modify my logging to either name the object or its type because sometimes I have multiple objects on the same line. It's not the end of the world, but in the end it would save me a few minutes each day. Any ideas on how I can pass the info on which object wasn't set? Thanks

    Read the article

  • Event handling for a dynamically added user control

    - by francisf
    Hi, I have a user control say SearchVendor.ascx which contains 4 buttons a gridview and another user control. I need to load the control dynamically actually as a modal pop up I get this code VendorProductSearch uc = Page.LoadControl("~/Controls/Proposal/VendorProductSearch.ascx") as VendorProductSearch; uc.ShowVendorProductSearch(true); _tempPlaceHolder.Controls.Add(uc); it works fine the control gets loaded properly but onclick of any button the second time the control disappears ??? I want the dynamically added control to remain until the user clicks on the cancel button Any idea as to how to achive this ? Thanks & Regards, Francis P.

    Read the article

  • Capture and handling the tab/Textchanged event in a textbox in asp.net MVC

    - by Icerman
    I have the following code th handle a user name validation on the server side. But the event seems not firing since break points in js or C# code didn't hit. Can anyone point out where I did wrong? Here is the user control which has a user name textbox: <%: Html.TextBox("UserName", Model.Username, new { maxlength = "40", size = "20", tabindex = "1", @onchange = "CheckAvailability()" })% CheckAvailability() is defined in the User.Validation.js and included in the above user control: $(document).ready(function () { function CheckAvailability() { $.post("/Home/Survey/CheckAvailability", { Username: $("#UserName").val() }, function (data) { var myObject = eval('(' + data + ')'); var newid = myObject; if (newid == 0) { $("#usernamelookupresult").html("<font color='green'>Available :-D</font>") } else { $("#usernamelookupresult").html("<font color='red'>Taken :-(</font>") } }); } }); Here is the survey controller function which will have server side validation: [HttpPost] public ActionResult CheckAvailability(string Username) { int Taken = 0; // This is where you add your database lookup if (Username == "abc") { Taken = 1; } return Json(Taken); }

    Read the article

  • Should I ignore the occasional Invalid viewstate error?

    - by Richard Ev
    Every now and then (once every day or so) we're seeing the following types of errors in our logs for an ASP.NET 3.5 application Invalid viewstate Invalid postback or callback argument Are these something that "just happens" from time-to-time with an ASP.NET application? Would anyone recommend we spend a lot of time trying to diagnose what's causing the issues?

    Read the article

  • Handling multiple media queries in Sass with Twitter Bootstrap

    - by Keith
    I have a Sass mixin for my media queries based on Twitter Bootstrap's responsive media queries: @mixin respond-to($media) { @if $media == handhelds { /* Landscape phones and down */ @media (max-width: 480px) { @content; } } @else if $media == small { /* Landscape phone to portrait tablet */ @media (max-width: 767px) {@content; } } @else if $media == medium { /* Portrait tablet to landscape and desktop */ @media (min-width: 768px) and (max-width: 979px) { @content; } } @else if $media == large { /* Large desktop */ @media (min-width: 1200px) { @content; } } @else { @media only screen and (max-width: #{$media}px) { @content; } } } And I call them throughout my SCSS file like so: .link { color:blue; @include respond-to(medium) { color: red; } } However, sometimes I want to style multiple queries with the same styles. Right now I'm doing them like this: .link { color:blue; /* this is fine for handheld and small sizes*/ /*now I want to change the styles that are cascading to medium and large*/ @include respond-to(medium) { color: red; } @include respond-to(large) { color: red; } } but I'm repeating code so I'm wondering if there is a more concise way to write it so I can target multiple queries. Something like this so I don't need to repeat my code (I know this doesn't work): @include respond-to(medium, large) { color: red; } Any suggestions on the best way to handle this?

    Read the article

  • Handling auto-incrementing IDENTITY SQL Server fields with LINQ to SQL in C#

    - by Maxim Z.
    I'm building an ASP.NET MVC site that uses LINQ to SQL to connect to SQL Server, where I have a table that has an IDENTITY bigint primary key column that represents an ID. In one of my code methods, I need to create an object of that table to get its ID, which I will place into another object based on another table (FK-to-PK relationship). At what point is the IDENTITY column value generated and how can I obtain it from my code? Is the right approach to: Create the object that has the IDENTITY column Do an InsertOnSubmit() and SubmitChanges() to submit the object to the database table Get the value of the ID property of the object

    Read the article

  • Show friendly message on ASP.NET Ajax error

    - by balexandre
    You all know how annoying is this: I do have a log system and the correct error is well explicit there, but I want to give a better message to the user. I keep trying several ways but I'm using Telerik components and well jQuery and I ended up using both ASP.NET Ajax methods and jQuery, so I use function pageLoad() { try { var manager = Sys.WebForms.PageRequestManager.getInstance(); manager.add_endRequest(endRequest); manager.add_beginRequest(OnBeginRequest); manager } catch (err) { alert(err); } } as well $(document).ready(function() { ... } that alert(err) is never fired even upon OnClick events what's the best approach to avoid this message errors and provide a cleaner way? all this happens in <asp:UpdatePanel> as I use that when I didn't know better (3 years ago!) and I really don't want to mess up and build all again from scratch :( Any help is greatly appreciated Updated with more error windows after volpav solution

    Read the article

  • Magento: Why do controller action predispatch events not fire if the controller is rewritten?

    - by mattalexx
    Why do controller action predispatch events not fire if the controller is rewritten? Here is a snippet of store/app/code/core/Mage/Core/Controller/Varien/Action.php: abstract class Mage_Core_Controller_Varien_Action { // [...] public function preDispatch() { // [...] if ($this->_rewrite()) { return; // [What is the purpose if this?] } // [...] // [This is where my event needs to be firing, but this code never gets // executed because the controller is rewritten] Mage::dispatchEvent( 'controller_action_predispatch_'.$this->getFullActionName(), array('controller_action'=>$this) ); } // [...] } I don't know where to start fixing this problem. Anyone out there ever dealt with this before?

    Read the article

  • Method with throws Exception: Where is it actually handled?

    - by Esq
    Here is an example code, I am throwing an exception here, it works perfectly fine without the try/catch block of code for some reason. Do I have to handle this inside this method "EntryDelete" or Do I have to handle this where the method is called from? If so can I see an example, what do I have to import in there? What is the acceptable syntax or method to do this? public boolean EntryDelete(int entryId) throws SQLException{ this.open(); kDatabase.delete(kENTRY_TABLE, kENTRY_ENTRY_ID + "=" + entryId, null); this.close(); return true; } Thanks

    Read the article

  • Are event handlers in JavaScript called in order?

    - by musicfreak
    I know this is a simple question, but I haven't had the chance to test it in any browser other than Firefox. If I attach multiple event handlers to a single event on a single DOM element, are the event handlers guaranteed to be called in the order they were added? Or should I not rely on this behavior?

    Read the article

  • Strange problem with Random Access Filing in C++

    - by sam
    This is a simple random access filing program . The problem arises where i want to write data randomly. If I write any where in the file the previous records are set to 0. the last 1 which is being entered currently holds the correct value all others =0. This is the code #include <iostream> #include<fstream> #include<string> using namespace std; class name { int id; int pass; public: void writeBlank(); void writedata(); void readdata(); void readall(); int getid() { return id; } int getpass() { return pass; } void setid(int i) { id=i; } void setpass(int p) { pass=p; } }; void name::writeBlank() { name person; person.setid(0); person.setpass(0); int i; ofstream out("pass.txt",ios::binary); if ( !out ) { cout << "File could not be opened." << endl; } for(i=0;i<10;i++) //make 10 records { cout<<"Put pointer is at: "<<out.tellp()<<endl; cout<<"Blank record "<<i<<" is: "<<person.getid()<<" "<<person.getpass()<<" and size: "<<sizeof(person)<<endl; cout<<"Put pointer is at: "<<out.tellp()<<endl; out.write(reinterpret_cast< const char * >(&person),sizeof(name)); } } void name::writedata() { ofstream out("pass.txt",ios::binary|ios::out); name n1; int iD,p; cout<<"ID?"; cin>>iD; n1.setid(iD); cout<<"Enter password"; cin>>p; n1.setpass(p); if (!out ) { cout << "File could not be opened." << endl; } out.seekp((n1.getid()-1)*sizeof(name),ios::beg); //pointer moves to desired location where we have to store password according to its ID(index) cout<<"File pointer is at: "<<out.tellp()<<endl; out.write(reinterpret_cast<const char*> (&n1), sizeof(name)); //write on that pointed location } void name::readall() { name n1; ifstream in("pass.txt",ios::binary); if ( !in ) { cout << "File could not be opened." << endl; } in.read( reinterpret_cast<char *>(&n1), sizeof(name) ); while ( !in.eof() ) { // display record cout<<endl<<"password at this index is:"<<n1.getpass()<<endl; cout<<"File pointer is at: "<<in.tellg()<<endl; // read next from file in.read( reinterpret_cast< char * >(&n1), sizeof(name)); } // end while } void name::readdata() { ifstream in("pass.txt",ios::binary); if ( !in ) { cout << "File could not be opened." << endl; } in.seekg((getid()-1)*sizeof(name)); //pointer moves to desired location where we have to read password according to its ID(index) cout<<"File pointer is at: "<<in.tellg()<<endl; in.read((char* )this,sizeof(name)); //reads from that pointed location cout<<endl<<"password at this index is:"<<getpass()<<endl; } int main() { name n1; cout<<"Enter 0 to write blank records"<<endl; cout<<"Enter 1 for new account"<<endl; cout<<"Enter 2 to login"<<endl; cout<<"Enter 3 to read all"<<endl; cout<<"Enter 9 to exit"<<endl; int option; cin>>option; while(option==0 || option==1 || option==2 || option==3) { if (option == 0) n1.writeBlank(); if(option==1) { /*int iD,p; cout<<"ID?"; cin>>iD; n1.setid(iD); cout<<"Enter password"; cin>>p; n1.setpass(p);*/ n1.writedata(); } int ind; if(option==2) { cout<<"Index?"; cin>>ind; n1.setid(ind); n1.readdata(); } if(option == 3) n1.readall(); cout<<"Enter 0 to write blank records"<<endl; cout<<"Enter 1 for new account"<<endl; cout<<"Enter 2 to login"<<endl; cout<<"Enter 3 to read all"<<endl; cout<<"Enter 9 to exit"<<endl; cin>>option; } } I Cant understand Y the previous records turn 0.

    Read the article

  • Handling input from a keyboard wedge

    - by JDibble
    Following on from the question asked by Mykroft Best way to handle input from a keyboard “wedge” http://stackoverflow.com/questions/42437/best-way-to-handle-input-from-a-keyboard-wedge. I need to write a class that intercepts key strokes, if the input is determined to be from the keyboard wedge (as described in the above post) the data will be directed to POS classes to handle, otherwise they keystrokes must be passed on to be handled in windows in the normal manner. This raises two questions How can I intercept key strokes when not in a WinForm. How can I pass on the keypresses to windows. Thanks JDibble

    Read the article

  • Communication between layers in an application

    - by Petar Minchev
    Hi guys! Let's assume we have the following method in the business layer. What's the best practice to tell the UI layer that something went wrong and give also the error message? Should the method return an empty String when it was OK, otherwise the error message, or should it throw another exception in the catch code wrapping the caught exception? If we choose the second variant then the UI should have another try,catch which is too much try,catch maybe. Here is a pseudocode for the first variant. public String updateSomething() { try { //Begin transaction here dataLayer.do1(); dataLayer.do2(); dataLayer.doN(); } catch(Exception exc) { //Rollback transaction code here return exc.message; } return ""; } Is this a good practice or should I throw another exception in the catch(then the method will be void)?

    Read the article

< Previous Page | 48 49 50 51 52 53 54 55 56 57 58 59  | Next Page >