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  • How to use App.Xaml's ResourseDictionaries with own entry point

    - by Polaris
    Hello friends. I created some logic for singleInstance application and I must to use my own entry point (not App.xaml) for Application. I have some styles in App.xaml which now is not working. How can I use this ResourceDictionaries from my App.xaml for entire project in my situation? My class for manage Application Startup public class SingleInstanceManager : WindowsFormsApplicationBase { App app; public SingleInstanceManager() { this.IsSingleInstance = true; } protected override bool OnStartup(Microsoft.VisualBasic.ApplicationServices.StartupEventArgs e) { try { // First time app is launched app = new App(); App.Current.Properties["rcID"] = e.CommandLine; //IntroLibrary.OpenDocumentFromNotify(); app.Run(); return false; } catch (Exception ex) { MessageBox.Show(ex.Message); return false; } } protected override void OnStartupNextInstance(StartupNextInstanceEventArgs eventArgs) { // Subsequent launches base.OnStartupNextInstance(eventArgs); Intro win = (Intro)app.MainWindow; if (eventArgs != null) { App.Current.Properties["rcID"] = eventArgs.CommandLine[0]; } IntroLibrary.OpenDocumentFromNotify(); app.Activate(); } } and my own Entry Point: public class EntryPoint { [STAThread] public static void Main(string[] args) { SingleInstanceManager manager = new SingleInstanceManager(); manager.Run(args); } } And my App.Xaml code behind: public partial class App : Application { protected override void OnStartup(System.Windows.StartupEventArgs e) { base.OnStartup(e); // Create and show the application's main window Intro window = new Intro(); window.Show(); } public void Activate() { // Reactivate application's main window this.MainWindow.Activate(); } } And my App.xaml has some code which decribe ResourceDictionaries which doesnt work. Why?

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  • C++: Simple data type for a variable in IF statement?

    - by Jason
    I am new to C++ and am making a simple text RPG, anyway, The scenario is I have a "welcome" screen with choices 1-3, and have a simple IF statement to check them, here: int choice; std::cout << "--> "; std::cin >> choice; if(choice == 1) { //.. That works fine, but if someone enters a letter as selection (instead of 1, 2 or 3) it'll become "-392493492"or something and crash the program. So I came up with: char choice; std::cout << "--> "; std::cin >> choice; if(choice == 1) { //.. This works kinda fine, but when I enter a number it seems to skip the IF statements completely.. Is the char "1" the same as the number 1? I get a compiler errro with this (ISO-CPP or something): if(choice == "1") So how on earth do I see if they entered 1-3 correctly!?

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  • Guidance on E-commerce in a Python Framework

    - by Ant
    I am looking for guidance in making decisions on using Python for E-commerce. My reasoning to use Python in the first place is i do a lot of 3D so it's a real help to use Python for web server side as well as 3D so I do not need to learn a new language. When I say E-commerce i mean the logic behind displaying products and a check out system that is Robust....and yes I really want to build this myself so I can change it. I do not want to use an out the box solution that costs a lot of money every month. I want control of server side, data bases, e-commerce etc. My questions are: What Frameworks are out there? I looked at previous questions on stackoverflow but only found old posts about Sachmo and Get paid. What is the learning path, I do not want to make a mistake that costs six months of studying? Python then Django? How long if I spent 10 hours a day studying this would it take to get up and running? I write javaScript badly, so I am not a complete noob, I understand the basics of programming languages. many thanks in advance

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  • Asynchronous Controller is blocking requests in ASP.NET MVC through jQuery

    - by Jason
    I have just started using the AsyncController in my project to take care of some long-running reports. Seemed ideal at the time since I could kick off the report and then perform a few other actions while waiting for it to come back and populate elements on the screen. My controller looks a bit like this. I tried to use a thread to perform the long task which I'd hoped would free up the controller to take more requests: public class ReportsController : AsyncController { public void LongRunningActionAsync() { AsyncManager.OutstandingOperations.Increment(); var newThread = new Thread(LongTask); newThread.Start(); } private void LongTask() { // Do something that takes a really long time //....... AsyncManager.OutstandingOperations.Decrement(); } public ActionResult LongRunningActionCompleted(string message) { // Set some data up on the view or something... return View(); } public JsonResult AnotherControllerAction() { // Do a quick task... return Json("..."); } } But what I am finding is that when I call LongRunningAction using the jQuery ajax request, any further requests I make after that back up behind it and are not processed until LongRunningAction completes. For example, call LongRunningAction which takes 10 seconds and then call AnotherControllerAction which is less than a second. AnotherControllerAction simply waits until LongRunningAction completes before returning a result. I've also checked the jQuery code, but this still happens if I specifically set "async: true": $.ajax({ async: true, type: "POST", url: "/Reports.aspx/LongRunningAction", dataType: "html", success: function(data, textStatus, XMLHttpRequest) { // ... }, error: function(XMLHttpRequest, textStatus, errorThrown) { // ... } }); At the moment I just have to assume that I'm using it incorrectly, but I'm hoping one of you guys can clear my mental block!

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  • wpautop() - when shortcode attributes are on new lines -breaks args array

    - by Luca
    I have a custom shortcode tag with a few attributes, and I would like to be able to display its attributes on new lines - to make it more readable to content editors: [component attr1 ="value1" attr2 ="value of the second one" attr3 ="another" attr4 ="value" ... attrN ="valueN"] The reason behind this requirement is that a few attributes might be quite verbose in content. Unfortunately, wpautop() adds some nasty extra markup that breaks the args array like this (using php print_r($args)): Array ( [0] => attr1 [1] => ="value1" /> [3] => attr2 = [4] => "value [5] => of [6] => the [7] => second [8] => one" /> [10] => "" //...and more like this) I've tried with the attributes inline: [component attr1 ="value1" attr2 ="value of the second one" ="value"... attrN ="valueN"] and the output is as expected: Array ( [attr1] => value1 [attr2] => value of the second one [attr3] => //...and so on) is there any way to have the attributes intented and avoid that extra markup that breaks the $args array?

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  • GetLongPathName Undeclared

    - by iwizardpro
    When I try to compile my code with the function GetLongPathName(), the compiler tells me that the function is undeclared. I have already read the MSDN documentation located @ http://msdn.microsoft.com/en-us/library/aa364980%28VS.85%29.aspx. But, even though I included those header files, I am still getting the undeclared function error. Which header file(s) am I supposed to include when using the function? #include <Windows.h> #include <WinBase.h> #define DLLEXPORT extern "C" __declspec(dllexport) DLLEXPORT char* file_get_long(char* path_original) { long length = 0; TCHAR* buffer = NULL; if(!path_original) { return "-10"; } length = GetLongPathName(path_original, NULL, 0); if(length == 0) { return "-10"; } buffer = new TCHAR[length]; length = GetLongPathName(path_original, buffer, length); if(length == 0) { return "-10"; } return buffer; } And, if it makes a difference, I am currently compiling using Dev-C++ on a Windows Vista 64-bit.

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  • [c++] accessing the hidden 'this' pointer

    - by Kyle
    I have a GUI architecture wherein elements fire events like so: guiManager->fireEvent(BUTTON_CLICKED, this); Every single event fired passes 'this' as the caller of the event. There is never a time I dont want to pass 'this', and further, no pointer except for 'this' should ever be passed. This brings me to a problem: How can I assert that fireEvent is never given a pointer other than 'this', and how can I simplify (and homogenize) calls to fireEvent to just: guiManager->fireEvent(BUTTON_CLICKED); At this point, I'm reminded of a fairly common compiler error when you write something like this: class A { public: void foo() {} }; class B { void oops() { const A* a = new A; a->foo(); } }; int main() { return 0; } Compiling this will give you ../src/sandbox.cpp: In member function ‘void B::oops()’: ../src/sandbox.cpp:7: error: passing ‘const A’ as ‘this’ argument of ‘void A::foo()’ discards qualifiers because member functions pass 'this' as a hidden parameter. "Aha!" I say. This (no pun intended) is exactly what I want. If I could somehow access the hidden 'this' pointer, it would solve both issues I mentioned earlier. The problem is, as far as I know you can't (can you?) and if you could, there would be outcries of "but it would break encapsulation!" Except I'm already passing 'this' every time, so what more could it break. So, is there a way to access the hidden 'this', and if not are there any idioms or alternative approaches that are more elegant than passing 'this' every time?

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  • C# Automatic Properties - Still null after +=?

    - by Sam Schutte
    This seems like a bug to me... I accept that automatic properties, defined as such: public decimal? Total { get; set; } Will be null when they are first accessed. They haven't been initialized, so of course they are null. But, even after setting their value through +=, this decimal? still remains null. So after: Total += 8; Total is still null. How can this be correct? I understand that it's doing a (null + 8), but seems strange that it doesn't pick up that it means it should just be set to 8... Addendums: I made the "null + 8" point in my question - but notice that it works with strings. So, it does null + "hello" just fine, and returns "hello". Therefore, behind the scenes, it is initializing the string to a string object with the value of "hello". The behavior should be the same for the other types, IMO. It might be because a string can accept a null as a value, but still, a null string is not an initialized object, correct? Perhaps it's just because a string isn't a nullable...

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  • LINQ to SQL Queries odd Materialization

    - by ptoinson
    I ran across an interesting Linq to SQL, uh, feature, the other day. Perhaps someone can give me a logical explanation for the reasoning behind the results. Take the code below as my example which utilizes the AdventureWorks database setup in a Linq to SQL DataContext. This is a clip from my unit test. The resulting customer returned from a call to both CustomerQuery_Test_01() and CustomerQuery_Test_02() is the same. However, the query executed on the SQLServer are different is a major way. The method CustomerQuery_Test_01 us causing the entire Customer table to be materialized, which the call to CustomerQuery_Test_02 is only causing the single customer to be materialized. The resulting SQL Queries are at the bottom of this post. Anyone have a good reason for this? To me, it was highly non-intuitive. protected virtual Customer GetByPrimaryKey(Func<Customer, bool> keySelection) { AdventureWorksDataContext context = new AdventureWorksDataContext(); return (from r in context.Customers select r).SingleOrDefault(keySelection); } [TestMethod] public void CustomerQuery_Test_01() { Customer customer = GetByPrimaryKey(c => c.CustomerID == 2); } [TestMethod] public void CustomerQuery_Test_02() { AdventureWorksDataContext context = new AdventureWorksDataContext(); Customer customer = (from r in context.Customers select r).SingleOrDefault(c => c.CustomerID == 2); } Query for CustomerQuery_Test_01 (notice the lack of a where clause) SELECT [t0].[CustomerID], [t0].[NameStyle], [t0].[Title], [t0].[FirstName], [t0].[MiddleName], [t0].[LastName], [t0].[Suffix], [t0].[CompanyName], [t0].[SalesPerson], [t0].[EmailAddress], [t0].[Phone], [t0].[PasswordHash], [t0].[PasswordSalt], [t0].[rowguid], [t0].[ModifiedDate] FROM [SalesLT].[Customer] AS [t0] Query for CustomerQuery_Test_02 (notice the where clause) SELECT [t0].[CustomerID], [t0].[NameStyle], [t0].[Title], [t0].[FirstName], [t0].[MiddleName], [t0].[LastName], [t0].[Suffix], [t0].[CompanyName], [t0].[SalesPerson], [t0].[EmailAddress], [t0].[Phone], [t0].[PasswordHash], [t0].[PasswordSalt], [t0].[rowguid], [t0].[ModifiedDate] FROM [SalesLT].[Customer] AS [t0] WHERE [t0].[CustomerID] = @p0

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  • variables in abstract classes C++

    - by wyatt
    I have an abstract class CommandPath, and a number of derived classes as below: class CommandPath { public: virtual CommandResponse handleCommand(std::string) = 0; virtual CommandResponse execute() = 0; virtual ~CommandPath() {} }; class GetTimeCommandPath : public CommandPath { int stage; public: GetTimeCommandPath() : stage(0) {} CommandResponse handleCommand(std::string); CommandResponse execute(); }; All of the derived classes have the member variable 'stage'. I want to build a function into all of them which manipulates 'stage' in the same way, so rather than defining it many times I thought I'd build it into the parent class. I moved 'stage' from the private sections of all of the derived classes into the protected section of CommandPath, and added the function as follows: class CommandPath { protected: int stage; public: virtual CommandResponse handleCommand(std::string) = 0; virtual CommandResponse execute() = 0; std::string confirmCommand(std::string, int, int, std::string, std::string); virtual ~CommandPath() {} }; class GetTimeCommandPath : public CommandPath { public: GetTimeCommandPath() : stage(0) {} CommandResponse handleCommand(std::string); CommandResponse execute(); }; Now my compiler tells me for the constructor lines that none of the derived classes have a member 'stage'. I was under the impression that protected members are visible to derived classes? The constructor is the same in all classes, so I suppose I could move it to the parent class, but I'm more concerned about finding out why the derived classes aren't able to access the variable. Also, since previously I've only used the parent class for pure virtual functions, I wanted to confirm that this is the way to go about adding a function to be inherited by all derived classes.

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  • Very simple code for number search gives me infinite loop

    - by Joshua
    Hello, I am a newbie Computer Science high school student and I have trouble with a small snippet of code. Basically, my code should perform a basic CLI search in an array of integers. However, what happens is I get what appears to be an infinite loop (BlueJ, the compiler I'm using, gets stuck and I have to reset the machine). I have set break points but I still don't quite get the problem...(I don't even understand most of the things that it tells me) Here's the offending code (assume that "ArrayUtil" works, because it does): import java.util.Scanner; public class intSearch { public static void main(String[] args) { search(); } public static void search() { int[] randomArray = ArrayUtil.randomIntArray(20, 100); Scanner searchInput = new Scanner(System.in); int searchInt = searchInput.nextInt(); if (findNumber(randomArray, searchInt) == -1) { System.out.println("Error"); }else System.out.println("Searched Number: " + findNumber(randomArray, searchInt)); } private static int findNumber(int[] searchedArray, int searchTerm) { for (int i = 0; searchedArray[i] == searchTerm && i < searchedArray.length; i++) { return i; } return -1; } } This has been bugging me for some time now...please help me identify the problem!

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  • Ruby & ActiveRecord: referring to integer fields by (uniquely mapped) strings

    - by JP
    While its not my application a simple way to explain my problem is to assume I'm running a URL shortener. Rather than attempt to try and figure out what the next string I should use as the unique section of the URL, I just index all my URLs by integer and map the numbers to strings behind the scenes, essentially just changing the base of the number to, let's say, 62: a-z + A-Z + 0-9. In ActiveRecord I can easily alter the reader for the url_id field so that it returns my base 62 string instead of the number being stored in the database: class Short < ActiveRecord::Base def url_id i = read_attribute(:convo) return '0' if i == 0 s = '' while i > 0 s << CHARS[i.modulo(62)] i /= 62 end s end end but is there a way to tell ActiveRecord to accept Short.find(:first,:conditions=>{:url_id=>'Ab7'}), ie. putting the 'decoding' logic into my Short ActiveRecord class? I guess I could define my own def self.find_by_unique_string(string), but that feels like cheating somehow! Thanks!

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  • Any workarounds for non-static member array initialization?

    - by TomiJ
    In C++, it's not possible to initialize array members in the initialization list, thus member objects should have default constructors and they should be properly initialized in the constructor. Is there any (reasonable) workaround for this apart from not using arrays? [Anything that can be initialized using only the initialization list is in our application far preferable to using the constructor, as that data can be allocated and initialized by the compiler and linker, and every CPU clock cycle counts, even before main. However, it is not always possible to have a default constructor for every class, and besides, reinitializing the data again in the constructor rather defeats the purpose anyway.] E.g. I'd like to have something like this (but this one doesn't work): class OtherClass { private: int data; public: OtherClass(int i) : data(i) {}; // No default constructor! }; class Foo { private: OtherClass inst[3]; // Array size fixed and known ahead of time. public: Foo(...) : inst[0](0), inst[1](1), inst[2](2) {}; }; The only workaround I'm aware of is the non-array one: class Foo { private: OtherClass inst0; OtherClass inst1; OtherClass inst2; OtherClass *inst[3]; public: Foo(...) : inst0(0), inst1(1), inst2(2) { inst[0]=&inst0; inst[1]=&inst1; inst[2]=&inst2; }; }; Edit: It should be stressed that OtherClass has no default constructor, and that it is very desirable to have the linker be able to allocate any memory needed (one or more static instances of Foo will be created), using the heap is essentially verboten. I've updated the examples above to highlight the first point.

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  • I want a function to return a type of the subclass its invoked from

    - by Jay
    I want to have a function defined in a superclass that returns a value of the type of the subclass that is used to invoke the function. That is, say I have class A with a function plugh. Then I create subclasses B and C that extend A. I want B.plugh to return a B and C.plugh to return a C. Yes, they could return an A, but then the caller would have to either cast it to the right subtype, which is a pain when used a lot, or declare the receiving variable to be of the supertype, which loses type safety. So I was trying to do this with generics, writing something like this: class A<T extends A> { private T foo; public T getFoo() { return foo; } } class B extends A<B> { public void calcFoo() { foo=... whatever ... } } class C extends A<C> { public void calcFoo() { foo=... whatever ... } } This appears to work but it looks pretty ugly. For one thing, I get warnings on "class A". The compiler says that A is generic and I should specify the type. I guess it wants me to say "class A". But what would I put in for x? I think I could get stuck in an infinite loop here. It seems weird to write "class B extends A", but this causes no complaints, so maybe that's just fine. Is this the right way to do it? Is there a better way?

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  • C++ template type deduction problem

    - by hamishmcn
    motivation: I would like to create a utility class so that instead of having to write: if( someVal == val1 || someVal == val2 || someVal == val3 ) I could instead write: if( is(someVal).in(val1, val2, val3) ) which is much closer to the mathematical 'a is an element of (b,c,d)' and also would save on a lot of typing when the variable name 'someVal' is long. Here is the code I have so far (for 2 and 3 values): template<class T> class is { private: T t_; public: is(T t) : t_(t) { } bool in(const T& v1, const T& v2) { return t_ == v1 || t_ == v2; } bool in(const T& v1, const T& v2, const T& v3) { return t_ == v1 || t_ == v2 || t_ == v3; } }; However it fails to compile if I write: is(1).in(3,4,5); instead I have to write is<int>(1).in(3,4,5); Which isn't too bad, but it would be better if somehow the compiler could figure out that the type is int with out me having to explicitly specify it. Is there anyway to do this or I am stuck with specifying it explicitly?

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  • How to find unmapped properties in a NHibernate mapped class?

    - by haarrrgh
    I just had a NHibernate related problem where I forgot to map one property of a class. A very simplified example: public class MyClass { public virtual int ID { get; set; } public virtual string SomeText { get; set; } public virtual int SomeNumber { get; set; } } ...and the mapping file: <?xml version="1.0" encoding="utf-8" ?> <hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" assembly="MyAssembly" namespace="MyAssembly.MyNamespace"> <class name="MyClass" table="SomeTable"> <property name="ID" /> <property name="SomeText" /> </class> </hibernate-mapping> In this simple example, you can see the problem at once: there is a property named "SomeNumber" in the class, but not in the mapping file. So NHibernate will not map it and it will always be zero. The real class had a lot more properties, so the problem was not as easy to see and it took me quite some time to figure out why SomeNumber always returned zero even though I was 100% sure that the value in the database was != zero. So, here is my question: Is there some simple way to find this out via NHibernate? Like a compiler warning when a class is mapped, but some of its properties are not. Or some query that I can run that shows me unmapped properties in mapped classes...you get the idea. (Plus, it would be nice if I could exclude some legacy columns that I really don't want mapped.)

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  • .net web service annoying issue

    - by JL
    Excuse the title, but it's best I just explain the problem. I have 2 projects in my solution A Class Library A Web Application, which consists of a web service (asmx). the web service has code sitting in the app_code folder, with a file [webservicename].cs Inside the webservice code behind class, I have a web method here is a sample example (its simplified): [WebMethod] public EnumTaskExportState ProcessTask() { var tm = new UploadTaskManager(); return tm.ProcessTask(); } Now at design time, in visual studio (2010 or 2008), when I right click on UploadTaskMananger, and then select "Go to definition". I get taken to AppData\Temp[some folder structure]...etc.... and it displays the public class definition. Instead I would like to have complete integration, so that I get taken directly to the actual class in the class library project. My guess is, this is happening because I am using the app_code route, and not a compiled file for the web service class. But I don't know any other way to do this. How can I fix this? Possibly do away with the need for the app_code directory?

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  • IE8, XHTML, position: fixed; and z-index.

    - by Joel
    I have an XHTML 1.0 transitional Doctype. I have a <div> that is position: fixed; bottom: 0px; left: 0px; width: 100%; z-index: 200;. Inside that <div> I have two buttons which are position relative, aligned right, with a set z-index of 201; In Firefox the bar at the bottom and the two buttons are correctly located at the bottom. In IE8 however, the bar is visible and the z-index appears to be overlaying the other content, but the buttons are hidden behind the main div, despite being children and having their z-index set. I'm using the following meta tag; <meta http-equiv="X-UA-Compatible" content="IE=edge" /> to force the document into IE8 mode. If I emulate IE7 (put on compatability mode), the bar and buttons work just fine. I don't understand how IE7's rendering is better than IE8. I don't want to have to force compatability mode due to other things that IE7 cannot render and IE8 can. Is there another solution, or have I missed something? Thanks.

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  • how to create an object using self?

    - by Nick
    I thought I understood the use of self while referring to anything in the current class. After encountering this warning and subsequent run failure, I have googled many variants of "define self" or "usage of self" and gotten nowhere. This problem is how to create an object without the warning, and understand why. #import <Cocoa/Cocoa.h> @interface Foo : NSObject { Foo *obj; } -(void)beta; @end #import "Foo.h" @implementation Foo -(void)beta{ obj = [self new]; // 'Foo' may not respond to '-new' } @end Note, if I substitute Foo for self, there's no problem. I thought the class name and self were equivalent, but obviously the compiler doesn't think so. Perhaps an explanation of what's wrong here will not only solve my problem but also enlighten my understanding of the usage of self. Are there any tutorials about proper usage of self? I couldn't find anything beyond something like "self is the receiver of the message," which I didn't help me at all.

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  • Detect that the onscreen keyboard has been displayed on Windows Phone 7

    - by David_001
    Simple question: How do I detect that the onscreen keyboard has been displayed on windows mobile 7? Is there an event I can add a listener to? It takes up about half the screen and I want to scroll the view up when it gets displayed... EDIT: A comment below indicates more clearly what I'm trying to do: I have a textbox input, and as the user types into it an autocomplete dropdown appears below it (like google suggest). By default, the active control (the textbox) scrolls into view when focussed, and the onscreen keyboard is directly below it. The onscreen keyboard appears in front of my autocomplete dropdown - what I want to do is make the screen scroll a little further up, so there's some room for my dropdown to be shown. The windows phone UI design guidelines say: "When the keyboard is deployed, the application should scroll to ensure the active edit control and the caret are in view". This happens fine, it's just the non-active dropdown gets hidden behind the onscreen keyboard. The guidelines also say that an application can choose to show the onscreen keyboard, and can also choose to close it. At the moment i'm stuck, and I don't think (based on my research and the replies to this question) that it's possible to detect that the onscreen keyboard has been displayed. I'm moving my investigation to see if it's possible to determine the "visible area" of the page (width & height in pixels for example), and combine this with an onfocus for the textbox... not sure if this will prove fruitful though.

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  • Why doesn't g++ pay attention to __attribute__((pure)) for virtual functions?

    - by jchl
    According to the GCC documentation, __attribute__((pure)) tells the compiler that a function has no side-effects, and so it can be subject to common subexpression elimination. This attribute appears to work for non-virtual functions, but not for virtual functions. For example, consider the following code: extern void f( int ); class C { public: int a1(); int a2() __attribute__((pure)); virtual int b1(); virtual int b2() __attribute__((pure)); }; void test_a1( C *c ) { if( c->a1() ) { f( c->a1() ); } } void test_a2( C *c ) { if( c->a2() ) { f( c->a2() ); } } void test_b1( C *c ) { if( c->b1() ) { f( c->b1() ); } } void test_b2( C *c ) { if( c->b2() ) { f( c->b2() ); } } When compiled with optimization enabled (either -O2 or -Os), test_a2() only calls C::a2() once, but test_b2() calls b2() twice. Is there a reason for this? Is it because, even though the implementation in class C is pure, g++ can't assume that the implementation in every subclass will also be pure? If so, is there a way to tell g++ that this virtual function and every subclass's implementation will be pure?

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  • please help me for performing serch in my program

    - by Abid
    i want to perform searching in my programe.. i have my class in which i have made a function i.e. public DataTable Search() { string SQL = "Select * from Customer where " + mField + " like '%" + mValue + "%'"; DataTable dt = new DataTable(); dt = dm.GetData(SQL); return (dt); } in which i have made setters and getters for mField and mValue.. where dm is the object of class Datamanagement in which i have made a function GetData i.e. public DataTable GetData(string SQL) { SqlCommand command = new SqlCommand(); SqlDataAdapter dbAdapter = new SqlDataAdapter(); DataTable DataTable = new DataTable(); command.Connection = clsConnection.GetConnection(); command.CommandText = SQL; dbAdapter.SelectCommand = command; dbAdapter.Fill(DataTable); return (DataTable); } and behind the search button, i have written.. private void btnfind_Click(object sender, EventArgs e) { //cust is the object of class customer// if (tbCustName.Text != "") { cust.Field="CustName"; cust.Value = tbCustName.Text; } else if (tbAddress.Text != "") { cust.Value = tbAddress.Text; cust.Field="Address"; } else if (tbEmail.Text != "") { cust.Value = tbEmail.Text; cust.Field="Email"; } else if (tbCell.Text != "") { cust.Value = tbCell.Text; cust.Field = "Cell"; } DataTable dt = new DataTable(); dt = cust.Search(); dgCustomer.DataSource = dt; RefreshGrid(); } where my referesh grid fuction does that : private void RefreshGrid() { DataTable dt = new DataTable(); dt = cust.GetCustomers(); dgCustomer.DataSource = dt; } but this is not working.. i dont knw y.. please help..

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  • Detecting what the target object is when NullReferenceException is thrown.

    - by StingyJack
    I'm sure we all have received the wonderfully vague "Object reference not set to instance of an Object" exception at some time or another. Identifying the object that is the problem is often a tedious task of setting breakpoints and inspecting all members in each statement. Does anyone have any tricks to easily and efficiently identify the object that causes the exception, either via programmatical means or otherwise? --edit It seems I was vague like the exception =). The point is to _not have to debug the app to find the errant object. The compiler/runtime does know that the object has been allocated, and that the object has not yet been instantiated. Is there a way to extract / identify those details in a caught exception @ W. Craig Trader Your explanation that it is a result of a design problem is probably the best answer I could get. I am fairly compulsive with defensive coding and have managed to get rid of most of these errors after fixing my habits over time. The remaining ones just tweak me to no end, and lead me to posting this question to the community. Thanks for everyone's suggestions.

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  • C++: Weird Segmentation fault.

    - by Kleas
    I am trying to print something using C++. However, I am running into a strange bug that has left me clueless, I use the following code: PRINTDLG pd; ZeroMemory(&pd, sizeof(pd)); pd.lStructSize = sizeof(pd); pd.Flags = PD_RETURNDEFAULT; PrintDlg(&pd); // Set landscape DEVMODE* pDevMode = (DEVMODE*)GlobalLock(pd.hDevMode); pDevMode->dmOrientation = DMORIENT_LANDSCAPE; pd.hwndOwner = mainWindow; pd.Flags = PD_RETURNDC | PD_NOSELECTION; GlobalUnlock(pd.hDevMode); if (PrintDlg(&pd)) { DOCINFO di; di.cbSize = sizeof(DOCINFO); di.lpszDocName = "Test Print"; di.lpszOutput = (LPTSTR)NULL; di.fwType = 0; //start printing StartDoc(pd.hDC, &di); int a; int b; int c; int d; int e; int f; // int g; // Uncomment this -> CRASH EndDoc(pd.hDC); DeleteDC(pd.hDC); } else { cout << "Did not print: " << CommDlgExtendedError() << endl; } The moment I uncomment 'int g;' I get a: "Program received signal SIGSEGV, Segmentation fault." I use codeblocks and the mingw compiler, both up to date. What could be causing this?

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  • Is there a way to make sure classes implementing an Interface implement static methods?

    - by Tobias Kienzler
    Frist of all, I read erickson's usefull reply to "Why can’t I define a static method in a Java interface?". This question is not about the "why" but about the "how then?". So basically I want one Interface to provide both usual methods and e.g. a getSimilarObject method. For (a made up) example public interface ParametricFunction { /** @return f(x) using the parameters */ static abstract public double getValue(double x, double[] parameters); /** @return The function's name */ static abstract public String getName(); } and then public class Parabola implements ParametricFunction { /** @return f(x) = parameters[0] * x² + parameters[1] * x + parameters[2] */ static public double getValue(double x, double[] parameters) { return ( parameters[2] + x*(parameters[1] + x*parameters[0])); } static public String getName() { return "Parabola"; } } Since this is not allowed in the current Java standard, what is the closest thing to this? The idea behind this is putting several ParametricFunction's in a package and use Reflection to list them all, allowing the user to pick e.g. which one to plot. Obviously one could provide a loader class containing an array of the available ParametricFunction's, but every time a new one is implemented one has to remember adding it there, too.

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