c# - 字符串值不能通过类方法赋值

Question

您好，我的 Windows 窗体应用程序中的类变量似乎有问题。

它是我的 Player 类中的一个 string 变量。当我创建 Player 对象时，我似乎无法将 string 值分配给 playerName 变量。

我已经手动创建了 Get 和 Set 方法，但我看不出有什么问题。

我多次收到一条消息，通知我字符串 playerName 未分配，并将保留其默认值 null。我不确定为什么会出现这种情况。

class Player
{

    private string playerName = ""; //Variable used for giving each player a unique identifier, eg. 'Player One', etc


    //public string PlayerName { get => playerName; set => playerName = value; }


    public void setPlayerName(string name) //Sets the player's name for the game (UNSC or Covenant)
    {
        name = this.playerName;
    }

    public string getPlayerName() //Returns the player's name
    {
        return playerName;
    }
}

创建 Player 类并尝试将 playerName 显示到文本框不起作用，playerName 值仍为 null

public partial class FrmBoardGameApp : Form
{
    public FrmBoardGameApp()
    {
        InitializeComponent();
    }

    ArrayList Players = new ArrayList();

    public void creationOfPlayers() //BUG!!! Values stay null
    {

        Player playerOne = new Player(); //Player 1
        Player playerTwo = new Player(); //Player 2
        playerOne.setPlayerName("Player One");
        playerTwo.setPlayerName("Player Two");

        Players.Add(playerOne); //Player name value is still null at this point
        Players.Add(playerTwo);
    }


    //Here's the textbox assignment code

    public bool playerTurn = true; //A bool variable used to keep track of whose turn it is
    public bool setupCheck = false; // Ensures that the endturn button cannot be hit unless all setup is done
    public int setupCheckValue = 0; //Ensures that the setup button can only be hit once

    public void testingPlayerTurn() //A method used to test whose turn it is
    {
        if (setupCheck != true)
        {
            MessageBox.Show("Game is not setup, please setup the game");
        }
        else
        {
            //Textbox is empty, as playerName value remains null
            if (playerTurn)
            {
                Players.ToArray();
                Player firstPlayer = (Player)Players[0];
                txtAns.Text = firstPlayer.getPlayerName();
                /*
                 * This method of accessing an element and controlling/manipulating its values works
                 */
            }
            else if (!playerTurn)
            {
                //playerTwo.setPlayerName(factionTwo);
                //txtAns.Text = playerTwo.getPlayerName();
            }
        }
    }


    private void btnEndTurn_Click(object sender, EventArgs e) //Ends the turn of the current player
    {
        changePlayer();
        //testingPlayerTurn();
        testingPlayerNames();
    }
}

我在代码示例中添加了一些处理玩家分配的方法，以防万一它有任何帮助。但问题始于 creationOfPlayers 方法和 Player 类。

Answer 1

这个:

public void setPlayerName(string name) //Sets the player's name for the game (UNSC or Covenant)
{
    name = this.playerName;
}

应该是相反的:

public void setPlayerName(string name) //Sets the player's name for the game (UNSC or Covenant)
{
    this.playerName = name;
}

问题:您实际上将字段的值分配给了方法的本地参数。

说明:=的左边应该是接收值的变量，右边应该是给出值的变量(或者在其他情况下是引用)。