Checking the Winner on Tic Tac Toe game on Windows Form Application - C++ -

i'm making tic-tac-toe game windows form application c++ class , need on making function find winner. in void winner function, i'm checking see if 3 squares match i'm not sure if condition in if statement right. program worked when added void winner function, didn't work. in advance.

private: system::void a1_click(system::object^  sender, system::eventargs^  e) {     bool turn = true;     if (turn)       a1->text = "x";     else       a1->text = "o";     turn = !turn;    winner(); }   void winner() {    if (a1 = a2 && a2 == a3)       label1-> text= "winner";            } 

in statement inside if(), have missed equal sign, might causing problem. assigning a1 a2. try this,

if (a1==a2 && a2==a3) 

also, think must trying compare text attribute of a1, a2 , a3. purpose use,

if(a1->text==a2->text && a2->text==a3->text)