Different variables and functions acting up

Question

As I'm coming from Python some things are still new to me. Getting this strange problem and I'm starting to feel stupid because I can't solve it, even when successfully declaring my variable "hwnd" it still throws an error, quite strange, if you need more details feel free to ask.

#include <iostream>
#include <TlHelp32.h>
#include <windows.h>

class GetHandleAndBase
{
private:
    HWND hwnd;
    DWORD procID;
    HANDLE handle;

public:
    GetHandleAndBase();
    ~GetHandleAndBase();

    // Setting the "hwnd" to a open window
    hwnd = FindWindow(NULL, L"Task Manager"); // <=====Error is under hwnd

(this declaration has no storage class or type specifier)

I should probably also mention that the function

GetWindowThreadProcessId(hwnd, &procID);

slightly later on in my class is messing up with the error: Function Definition for 'GetWindowThreadProcessId' not found

That's not how you set a variable. You can't just set some variable at some random place in your header or a cpp file. All executable statements must be in a function or a class method. — Sam Varshavchik, Feb 13 '18 at 11:55
Consider learning from a [good C++ book](https://stackoverflow.com/questions/388242/the-definitive-c-book-guide-and-list), instead of coding randomly. Executable code must be located in functions. — Algirdas Preidžius, Feb 13 '18 at 11:55

score 2 · Answer 1 · answered Feb 13 '18 at 11:58

Assignment and initialization are different concepts in C++. As such, the various scopes in which each may appear are also not always the same. Ultimately, hwnd = FindWindow(NULL, L"Task Manager"); is a statement, which may not appear in class scope.

But default member initializers may appear in class scope, so this:

class GetHandleAndBase
{
private:
    HWND hwnd = FindWindow(NULL, L"Task Manager");
//...

Would be perfectly fine. If however you need to run several statements as part of initializing GetHandleAndBase (odd name for a C++ class, btw), you should write that inside a constructors body.

Or an [IIFE](http://www.bfilipek.com/2016/11/iife-for-complex-initialization.html), that can work too. — Quentin, Feb 13 '18 at 13:00

Different variables and functions acting up

1 Answers1