Don’t remove elements while iterating over the collection with a foreach. Also, I’d recommend using List<T> rather than ArrayList. An easier way to solve the task at hand is to simply do: public static void Remove(List<Account> L, int accnb) => L.RemoveAll(obj => obj.AccN == accnb); 0 solved System.InvalidOperationException in my c# project
You want to overload << operator. For instance: ostream& operator<<(ostream& os, const Date& dt) { os << dt.mo << “https://stackoverflow.com/” << dt.da << “https://stackoverflow.com/” << dt.yr; return os; } If a() isn’t constructor, but only a () operator overloaded which I assumed changes the a field of the class A to the parameter provided inside … Read more
You are passing a pointer and a normal int to f, because int *a=new int(4), b(16); works like int *a=new int(4); int b(16); Thus, in f, you have T == int* and U == int, then you add the int to the pointer and return the resulting pointer. As it does not point to memory … Read more
Constructor create object in memory only, and once your app is closed or pc shutdown your data will be lost, store data in a file is useful to store application settings, you have to use an xml or a properties file. If you want to store your business or other data in a database, you … Read more
I think what you are trying to do is making your code dynamic. Unfortunately, you are doing it completely wrong. Please first clear your concept on enum. If this is the case, then you can try this- int a, b; char op; cin >> a >> op >> b; switch(op) { case ‘+’: cout << … Read more
You are creating an extra global instance c here: class cls1 { int x; cls xx; public: cls1(int i=0){cout<<” c2 “;x=i;} ~cls1(){cout<<” d2 “;} } c; // <– here That one is created first. Otherwise your expected order is spot-on. 2 solved C++ Constructor Oder [closed]
Since this is clearly a homework exercise, it is not appropriate for me to provide an answer directly. Instead, I have written a little program for you to demonstrate what the question means, and running it will provide an answer. You can try this out for yourself: public class Main { class A {} class … Read more
<?=?> is a Short Tag for echo(); According to PHP Outputs all parameters. echo is not actually a function (it is a language construct), so you are not required to use parentheses with it. echo (unlike some other language constructs) does not behave like a function, so it cannot always be used in the context … Read more
What I think you’re trying to achieve is that when you call your method “horn” with some parameter it has to either use “Beep!” or “Boop!”. First of: void horn(a,b) Is not a valid function signature in Java, in a java function you always have to specify what type the input you’re providing is. In … Read more
You only defined classes inside the namespace of class User. An instance of User don’t have magically instances of the inner classes (i.e. in Python there is nothing like a inner class). So class definitions inside other classes in normally not useful. You have to give the other classes an explicit reference to your user … Read more
Change it to: public static class ObjectsGlobal { public static Bays bay1 = new Bays(); public static bay10 = new Bays(); } Also, as recommended in a comment I have now read, take a look at the Singleton Pattern. solved C# Global Object [closed]
Java is oop but not pure because, There are Primitive data type in java like int, float etc. and they are not classes/Objects. This is only one reason that java is not Pure OOP. For example of Pure OOP . Objective C is Pure OOP language in which every thing is in the form of … Read more
First one is correct, second is not. By definition, a Child will inherit all properties and methods of a Parent; however, Parent will not have all properties and/or methods of a Child, so the second statement wouldn’t make sense: class Parent { public int ParentId { get; set; } public void Eat { … } … Read more
when we run application from IDE then how compiler come into scene to compile our program The IDE starts the compiler and passes it your program. The compiler is another program. It doesn’t need special invocation. You can do it yourself without an IDE by just calling csc.exe directly. and after then how program start….how … Read more
In python? why do the subclass inherit from parent? when you use the init of method to assign the parent?but it does not work [duplicate] solved In python? why do the subclass inherit from parent? when you use the init of method to assign the parent?but it does not work [duplicate]