IF语句未执行，但ELSE IF语句工作正常

Question

I've been learning Java and am working on a simple Tic-Tac-Toe game. I believe I've gotten everything working properly except for the IF statement not executing. So when the player gets three X's in a row or diagonally, the IF statement doesn't execute. However both the ELSE IF statements are working just fine whenever the players tie or get three O's. Any help would be much appreciated!

public static void check_status()
{
    if (    (board[0][0]=='X' && board[0][1]=='X' && board[0][2]=='x') ||
            (board[1][0]=='X' && board[1][1]=='X' && board[1][2]=='x') ||
            (board[2][0]=='X' && board[2][1]=='X' && board[2][2]=='x') ||

            (board[0][0]=='X' && board[1][0]=='X' && board[2][0]=='x') ||
            (board[0][1]=='X' && board[1][1]=='X' && board[2][1]=='x') ||
            (board[0][2]=='X' && board[1][2]=='X' && board[2][2]=='x') ||

            (board[0][0]=='X' && board[1][1]=='X' && board[2][2]=='x') ||
            (board[0][2]=='X' && board[1][1]=='X' && board[2][0]=='x') )
    {
        System.out.println();
        System.out.println("X wins the game!");
        end_game = 1;
    }

    else if (    (board[0][0]=='O' && board[0][1]=='O' && board[0][2]=='O') ||
            (board[1][0]=='O' && board[1][1]=='O' && board[1][2]=='O') ||
            (board[2][0]=='O' && board[2][1]=='O' && board[2][2]=='O') ||

            (board[0][0]=='O' && board[1][0]=='O' && board[2][0]=='O') ||
            (board[0][1]=='O' && board[1][1]=='O' && board[2][1]=='O') ||
            (board[0][2]=='O' && board[1][2]=='O' && board[2][2]=='O') ||

            (board[0][0]=='O' && board[1][1]=='O' && board[2][2]=='O') ||
            (board[0][2]=='O' && board[1][1]=='O' && board[2][0]=='O') )
    {
        System.out.println();
        System.out.println("O wins the game!");
        end_game = 1;
    }


    else if (   (board[0][0]!=' ' && board[0][1]!=' ' && board[0][2]!=' ') &&
                (board[1][0]!=' ' && board[1][1]!=' ' && board[1][2]!=' ') &&
                (board[2][0]!=' ' && board[2][1]!=' ' && board[2][2]!=' ') )
    {
        System.out.println();
        System.out.println("The game is a tie.");
        end_game = 1;
    }
}

Also this is the first time I've posted on Stack Overflow so apologies if the question or formatting is out of place.

Full Code:

import java.util.Scanner;

public class TicTacToe
{

    private static char[][] board = new char[3][3];

    private static int end_game = 0;

    public static void main( String[] args )
    {
        Scanner keyboard = new Scanner(System.in);

        initBoard();
        displayBoard();

        do
        {

            System.out.println();
            System.out.print("\'O\', choose your location (row, column): ");
            int O_row = keyboard.nextInt();
            int O_col = keyboard.nextInt();
            board[O_row][O_col] = 'O';
            System.out.println();
            displayBoard();
            check_status();
            if (end_game==1){
                break;
            }
            System.out.println();
            System.out.print("\'X\', choose your location (row, column): ");
            int X_row = keyboard.nextInt();
            int X_col = keyboard.nextInt();
            board[X_row][X_col] = 'X';
            System.out.println();
            displayBoard();
            check_status();

        } while (end_game==0);
    }

    public static void check_status()
    {
        if (    (board[0][0]=='X' && board[0][1]=='X' && board[0][2]=='x') ||
                (board[1][0]=='X' && board[1][1]=='X' && board[1][2]=='x') ||
                (board[2][0]=='X' && board[2][1]=='X' && board[2][2]=='x') ||

                (board[0][0]=='X' && board[1][0]=='X' && board[2][0]=='x') ||
                (board[0][1]=='X' && board[1][1]=='X' && board[2][1]=='x') ||
                (board[0][2]=='X' && board[1][2]=='X' && board[2][2]=='x') ||

                (board[0][0]=='X' && board[1][1]=='X' && board[2][2]=='x') ||
                (board[0][2]=='X' && board[1][1]=='X' && board[2][0]=='x') )
        {
            System.out.println();
            System.out.println("X wins the game!");
            end_game = 1;
        }

        else if (    (board[0][0]=='O' && board[0][1]=='O' && board[0][2]=='O') ||
                (board[1][0]=='O' && board[1][1]=='O' && board[1][2]=='O') ||
                (board[2][0]=='O' && board[2][1]=='O' && board[2][2]=='O') ||

                (board[0][0]=='O' && board[1][0]=='O' && board[2][0]=='O') ||
                (board[0][1]=='O' && board[1][1]=='O' && board[2][1]=='O') ||
                (board[0][2]=='O' && board[1][2]=='O' && board[2][2]=='O') ||

                (board[0][0]=='O' && board[1][1]=='O' && board[2][2]=='O') ||
                (board[0][2]=='O' && board[1][1]=='O' && board[2][0]=='O') )
        {
            System.out.println();
            System.out.println("O wins the game!");
            end_game = 1;
        }


        else if (   (board[0][0]!=' ' && board[0][1]!=' ' && board[0][2]!=' ') &&
                    (board[1][0]!=' ' && board[1][1]!=' ' && board[1][2]!=' ') &&
                    (board[2][0]!=' ' && board[2][1]!=' ' && board[2][2]!=' ') )
        {
            System.out.println();
            System.out.println("The game is a tie.");
            end_game = 1;
        }
    }

    public static void initBoard()
    {
        // fills up the board with blanks
        for ( int r=0; r<3; r++ )
            for ( int c=0; c<3; c++ )
                board[r][c] = ' ';
    }


    public static void displayBoard()
    {
        System.out.println("  0  " + board[0][0] + "|" + board[0][1] + "|" + board[0][2]);
        System.out.println("    --+-+--");
        System.out.println("  1  " + board[1][0] + "|" + board[1][1] + "|" + board[1][2]);
        System.out.println("    --+-+--");
        System.out.println("  2  " + board[2][0] + "|" + board[2][1] + "|" + board[2][2]);
        System.out.println("     0 1 2 ");
    }

}

Answer 1

board[0][2]=='x' 

您在前两列中使用大X ，在最后一列中使用小x ，这可能是问题的根源

Answer 2

You should take a look at the X s and x s you are using in your code. Characters are case sensitive.