Hi! class Interface{}; class Foo: public Interface{}; class Bar{ public: vector<Interface*> getStuff(); private: vector<Foo*> stuff; }; how Do I implement the funtion getStuff() ? hope the question is clear.. Thanks! ...
Suppose I have two classes A and B. Both are identical (same atributes, methods, etc), but they are named different. There's some safe way, in Java, to cast a B object as an A object? ...
I'm trying to cast a pointer to an int (or unsigned int) and no matter what I try it doesn't want to work. I've tried static_cast<intptr_t>(obj), reinterpret_cast<intptr_t>(obj), and various combinations of C style casts, intptr_t's, unsigned int's, and I'm including stdint.h. From what I've read, one of the many things I've tried shou...
Hello guys. I have a method which receives a parameter of base type and performs some pre-processing depending on actual parameter type. Here is my code: public void OnMessageReceived(QuickFix42.Message message) { if (message is QuickFix42.ExecutionReport) { ProcessExecutionReport(message as QuickFix42.ExecutionReport);...
I ran into an issue today and I wasn't entirely sure why it wouldn't work. The following code sample will crash: static void Main(string[] args) { int i32 = 10; object obj = i32; long i64 = (long)obj; } This will result in an InvalidCastException. Why does this not work? Is C# not smart enough to know that the object...
Hello I'm having problems getting this to work, class A { public: A(int n) { a = n; } int getA() { return a; } private: int a; }; int main(){ A* a[3]; A* b[3]; for (int i = 0; i < 3; ++i) { a[i] = new A(i + 1); } void * pointer = a; b = (A* [])pointer; // DOESNT...
Hi, can anyone help me out. By implementing countermeasures in solving the concurrency problem I got troubled with passing timestamps (rowversion) between Powerbuilder 7 datawindow and SQLServer 2008 (both ways) using insert and update stored procedures. The connection is serviced by ODBC, not native. Most of my attempts result in cas...
i have a command line executable program that accepts a configuration file as it's one argument for launch. the configuration file contains only 2 lines of code: #ConfigFile.cfg name=geoffrey city=montreal currently, the wrapper program that i'm building for this command line executable program writes the configuration file to disk a...
Hi, I have some dataset with values and now I need to put that values into textbox but there is some decimal and double type values so I need to cast them toString() and it happens that sometime dataset values are empty so before casting toString() I need to check Is there any value ??? This is sample line: I need something like this...
Animal public abstract class Animal { String name; public Animal(String name) { this.name = name; } } Lion public class Lion extends Animal { public Lion(String name) { super(name); // TODO Auto-generated constructor stub } public void roar() { System.out.println("Roar"); } } Deer public class Deer extends Anima...
I have a base Entity class: public class Entity { abstract int getTypeID(); } The method int getTypeID() returns a number that is unique to that class: public class OneEntity extends Entity { int getTypeID() { return 1; // Actually defined in a constants class } } Now I want to be able to safely cast it and ...
I'm having to do some weird things with gcroot, but I get the following error on the dynamic cast line: "cannot use 'dynamic_cast' to convert from 'gcroot' to 'IMyInterface^'. In C#, you could easily cast a generic object to any interface. You may get a runtime error if the object doesn't implement the interface but it would compile. ...
Recently I answered another question asking for questions every decent C++ programmer should be able to answer. My suggestion was Q: How does a pointer point to an object? A: The pointer stores the address of that object. but user R.. disagrees with the A I propose to the Q - he says that The correct answer would be "it's implementati...
I'm implementing an int IComparer.Compare(object x, object y); from the IComparer interface. I know the objects are of type Class1, and I know one of its members is class1Instance.myDate, of type DateTime. What I want to do is something along the lines of: DateTime.Compare( (Class1)x.myDate, (Class1)y.myDate); But casting this w...
I feel stupid asking this but I am. The line List<HasId> ids = list is giving a compile error in the following code: public class MyGarbageClass { public void myMethod(List<MyCompany> list){ List<HasId> ids = list; } interface HasId { int getId(); } class MyCompany implements HasId{ private...
I'm using the default SqlMembershipProvider, but I've created a custom MembershipUser class (SoeMembershipUser) because I needed a "DisplayName" property. All the DisplayName does is look at the UserName and format it differently. When I try to cast a MembershipUser to a SoeMembershipUser user I get an InvalidCastException. Exact error ...
private final static int L1_MAX_SCORE = 30; private final static int L2_MAX_SCORE = 150; public void UpdateLevel(int score) { double progress; //returns 0.0 progress = score / (L2_MAX_SCORE - L1_MAX_SCORE) * 100; //works correctly. progress = (double) score / (L2_MAX_SCORE - L1_MAX_SCORE) * 100; Thanks. ...
(Please no advise that I should abstract X more and add another method to it.) In C++, when I have a variable x of type X* and I want to do something specific if it is also of type Y* (Y being a subclass of X), I am writing this: if(Y* y = dynamic_cast<Y*>(x)) { // now do sth with y } The same thing seems not possible in Java (or...
I have some code that binds an enumeration to a dropdown list, however, I'd like build the dropdown to take the integer value from the enum for the value and the description attribute for the text. I tried defining the kvPairList as a int/string and casting enumValue and an (int) I also tried converting.toInt32 Ideas? <select name=...
Why this explicit cast does throw Specified cast is not valid. exception ? decimal d = 10m; object o = d; int x = (int)o; But this works: int x = (int)(decimal)o; ...