'='左运算符一定是从 Visual Studio C 中的函数传递值时遇到的左值问题

Question

我正在 Visual Studio C 中编程。该程序包括监视垄断游戏，我想知道如何从函数传递结构矩阵的值，但它给了我错误 C2106（'=' 左运算符必须是 l -值）。

这是我在 main.c 中的代码：

campo = play(gioca, campo, &sortedPlayers, roundPlayer);
/*gioca and roundPlayer are both an int value
* sortedPlayers is a list of struct
* campo[][] is an matrix of struct (is the field of the game)
*/

这是我在头文件中的代码：

casa** play(int scelta, casa campo[DIM_CAMPO][DIM_CAMPO], playerlist* players, int idP);

这是我在 .c 文件中的代码：

casa** play(int scelta, casa campo[DIM_CAMPO][DIM_CAMPO], playerlist* players, int idP) {
    int dado1, dado2, isDadoDoppio, idx;
    player player;
    playerlist copiaPlayers = emptylistP(), defPlayers = emptylistP();
    switch (scelta) {
    case 0:
        exit(0);
        break;
    case 1:
        srand(time(NULL));
        dado1 = rand() % 6 + 1;
        dado2 = rand() % 6 + 1;
        printf("\nIl numero uscito e': %d + %d", dado1, dado2);
        if (dado1 == dado2)
            isDadoDoppio = 1;
        else
            isDadoDoppio = 0;

        copiaPlayers = *players;
        while (!emptyP(copiaPlayers)) {
            player = headP(copiaPlayers);

            /* Movimento giocatore */
            if (player.idP = idP) {
                for (idx = 0; idx < dado1 + dado2; idx++) {
                    //printf("\n[%d][%d] --> ", player.x, player.y);
                    if (player.x == 0 && (player.y <= 10 && player.y > 0))
                        player.y += 1;
                    else if (player.x == 10 && (player.y <= 10 && player.y > 0))
                        player.y -= 1;
                    else if (player.y == 0  && (player.x <= 10 && player.x > 0))
                        player.x -= 1;
                    else if (player.y == 10 && (player.x <= 10 && player.x > 0))
                        player.x += 1;
                    //printf("[%d][%d]", player.x, player.y);
                }
                break;
            }
            defPlayers = newPlayer(player, defPlayers);
            campo[player.x][player.y].simbolo = (char)player.idP;
            copiaPlayers = tailP(copiaPlayers);
        }

        break;
    }
    return campo;
}

Answer 1

campo = play(gioca, campo, ...

我敢打赌作业中的

campo

是一个数组。您无法分配数组。

此外，如果将 2D 数组作为参数传递，则无法返回指向指针的指针。数组不是指针！！！