c#3_3.cs

private bool CheckForWinner()
 {
     return CheckRows() || CheckColumns() || CheckDiagonals();
 }
 private bool CheckRows()
 {
     foreach (List row in fields)
     {
         if (row[0] != Player.None && row[0] == row[1] && row[1] == row[2])
         {
             return true;
         }
     }
     return false;
 }
 private bool CheckColumns()
 {
     for (var column_index = 0; column_index < FIELD_SIZE; column_index++)
     {
         if (fields[0][column_index] != Player.None
             && fields[0][column_index] == fields[1][column_index]
             && fields[1][column_index] == fields[2][column_index])
         {
             return true;
         }
     }
     return false;
 }
 private bool CheckDiagonals()
 {
     if (fields[0][0] != Player.None && fields[0][0] == fields[1][1]
         && fields[1][1] == fields[2][2])
     {
         return true;
     }
 if (fields[0][2] != Player.None && fields[1][1] == fields[2][0]
       && fields[1][1] == fields[0][2])
     {
         return true;
     }
     return false;
 }