Visual C++ .NET/Collections/count if
count_if and functor
<source lang="csharp">
- include "stdafx.h"
- include <cliext/vector>
- include <cliext/functional>
- include <cliext/algorithm>
using namespace System; using namespace cliext; using namespace System::Collections::Generic; ref class MyClass{ public:
String^ Name; MyClass() : Name(String::Empty) { } MyClass(String^ name) : Name(name) { } MyClass(const MyClass% orig){ Name = orig.Name; } MyClass% operator=(const MyClass% orig){ if (this != %orig) Name = orig.Name; return *this; } ~MyClass() { } bool operator<(const MyClass^ rhs){ return (Name->CompareTo(rhs->Name) < 0); } bool operator>(const MyClass^ rhs){ return (Name->CompareTo(rhs->Name) > 0); } bool operator==(const MyClass^ rhs) { return (Name->Equals(rhs->Name)); }
}; bool BeforeC(MyClass^ value){
MyClass^ c = gcnew MyClass("C"); return value > c;
} int main(array<System::String ^> ^args) {
vector<MyClass^> myCollection; myCollection.push_back(gcnew MyClass("A")); myCollection.push_back(gcnew MyClass("B")); myCollection.push_back(gcnew MyClass("C")); myCollection.push_back(gcnew MyClass("D")); for each (MyClass^ pet in myCollection) Console::Write("{0} ", pet->Name); Console::Write("\n\ncount_if(F,L, BeforeC()) is:\n "); Console::Write(count_if(myCollection.begin(), myCollection.end(), BeforeC).ToString()); return 0;
}
</source>