不断获取“未设置为对象实例的对象引用”.复制字符串时

本文关键字：对象引用 复制 字符串 实例 对象 获取 设置 | 更新日期: 2023-09-27 17:49:32

int PlayerAmount = 10;
int CurrentPlayer = 0;
Player[] player = new Player[PlayerAmount];
while (true)
{
    string Input;
    Console.WriteLine("What would you like to do?");
    Console.WriteLine("1. Create new player and score.");
    Console.WriteLine("2. Display Highscores.");
    Console.WriteLine("3. Write out to XML file.");
    Console.Write("Input Number: ");
    Input = Console.ReadLine();
    if (Input == "1")
    {
        if (CurrentPlayer >= PlayerAmount)
        {
            Console.WriteLine();
            Console.WriteLine("MAX AMOUNT OF PLAYERS HAS BEEN REACHED!");
            Console.WriteLine();
        }
        else
        {
            string PlayerName;
            string Score;
            Console.WriteLine();
            Console.WriteLine("-=CREATE NEW PLAYER=-");
            Console.Write("Player name: ");
            PlayerName = Console.ReadLine();
            Console.Write("Player score: ");
            Score = Console.ReadLine();
            //=========================================
            //THIS IS WHERE THE ERROR OCCURS===========
            //=========================================
            player[CurrentPlayer].Name = PlayerName;

            Console.WriteLine("Player '"" + player[CurrentPlayer].Name + "'" with the score of '"" + player[CurrentPlayer].Score + "'" has been created successfully!" );
            Console.WriteLine();
        }
    }
    else if (Input == "2")
    {
        Console.WriteLine("Displaying the highscores");
    }
    else if (Input == "3")
    {
        Console.WriteLine("Writing to XML file");
    }
    else
    {
        Console.WriteLine("INVALID INPUT");
    }
}

我已经尝试过使用字符串复制，但这只是给了我同样的错误，我已经在代码中指出了问题，但如果你看不见它的播放器名称被复制的地方:"播放器[CurrentPlayer]。Name = PlayerName;"

Thanks in advance

不断获取“未设置为对象实例的对象引用”.复制字符串时

不初始化Player数组的每个成员。后做:

Player[] player = new Player[PlayerAmount];

你可能也想这样做:

for (int i = 0; i < PlayerAmount; i++)
{
    Player[i] = new Player();
}

因为事先，数组只包含一堆null引用

看起来像:

player[CurrentPlayer].Name

是null。确保在currentPlayer索引处的播放器对象不为空。

初始化数组时，所有对象默认为null(非原语)。因此，您必须实例化数组中的每个索引中的每个播放器。

这一行:

Player[] player = new Player[PlayerAmount];

只分配一个大小为playerAmount的数组(在您的示例中为10);

你需要这个来初始化它们:

for(int i =0; i < player.length;i++)  
{  
     player[i] = new Player();
}

你也可以创建像

这样的"lazy-like"
player[CurrentPlayer] = new Player();
player[CurrentPlayer].Name = PlayerName;
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