c# - 文本框不会刷新文本，但是消息框会

Question

我在这个 Tron 游戏应用程序中使用了两个线程。我有一个 TextBox，它在每场比赛结束时显示分数。每个“游戏”都在第二个 drawThread 线程中绘制。

问题是，我在更改 TextBox.Text 后的一行中的 MessageBox 中显示分数，MessageBox 显示分数正常，但 TextBox 没有。

有什么想法吗？我确保使用线程安全调用(但是我正在更改创建它的线程中的文本)。有问题的代码在 createGame() 方法中，并且是

SetLabel(score);

public Form1()
        {
            InitializeComponent();
            canvas = game_panel.CreateGraphics();
            formCanvas = this.CreateGraphics();
            game_panel.Invalidate(true);
            bikes = new List<LightBike>();
            bikes.Add(new LightBike(new Point(game_panel.Size.Width - 25, game_panel.Height / 2), Color.Blue, "left", new DirectionKeys(Keys.Left, Keys.Down, Keys.Up, Keys.Right, Keys.Control)));
            bikes.Add(new LightBike(new Point(25, game_panel.Height/2), Color.Red, "right", new DirectionKeys(Keys.A, Keys.S, Keys.W, Keys.D, Keys.Q)));
            createGame();  
        }

        private void button1_Click(object sender, EventArgs e)
        {
            if (drawThread.ThreadState == ThreadState.Stopped)
            {
                InitializeComponent();
                createGame();
                drawThread.Start();
            }
            else
            {
                if(drawThread.ThreadState != ThreadState.WaitSleepJoin)
                    drawThread.Start();
            }
            button1.Text = "Play Again";

        }
public void SetLabel(string message)
        {

            if (this.textBox1.InvokeRequired)
                this.textBox1.Invoke((Action<string>)SetLabel, message);
            else
                this.textBox1.Text = message;
            MessageBox.Show(message); 
        }
 public void createGame()
        {   
             if (!firststart)
            {
                foreach (LightBike b in deleteBikes)
                {
                    if(b.color == Color.Blue)
                        bikes.Insert(0,b);
                    if (b.color == Color.Red)
                        bikes.Insert(1, b);
                }
                bikes[0].Redraw(new Point(game_panel.Size.Width - 25, game_panel.Height / 2), "left");
                bikes[1].Redraw(new Point(25, game_panel.Height / 2), "right");
            }
            drawThread = new Thread(drawBikes); 
            grid = new int[game_panel.Size.Width, game_panel.Size.Height]; //create the grid map

            game_panel.Update();

            String score = "";
            foreach (LightBike b in bikes)
            {
                score += b.toColorString() + ": " + b.score + " ";
            }
            SetLabel(score);
            textBox1.Refresh();        
        }

public void drawBikes()
        {
            String gameStatus = "WIN";

            deleteBikes = new List<LightBike>();
            while (true)
            {
                int tieCount = 0;

                foreach (LightBike b in bikes) //check collision
                {

                    if (!isValidLocation(b.location))
                    {
                        deleteBikes.Add(b);
                        tieCount++;
                    }
                }
                    foreach (LightBike b in deleteBikes)
                    {
                        //MessageBox.Show("DELETED BIKES: " + b.color.ToString());
                        bikes.Remove(b);
                    }
                    if (tieCount > bikes.Count) //if the deleteBikes contain more than the bikes
                    {
                        gameStatus = "TIE";
                        break;
                    }

                if (bikes.Count <= 1) //game over
                    break;

                foreach (LightBike b in bikes) //draw bikes
                {

                    //canvas.DrawLine(new Pen(b.color, BIKE_SIZE), b.getPreviousLocation(), b.location);
                    canvas.DrawLine(new Pen(b.color, BIKE_SIZE) { EndCap = System.Drawing.Drawing2D.LineCap.Square }, b.location, b.getNextLocation());
                    //MessageBox.Show("Bike "+b.color.ToString()+": "+Form1.ActiveForm.GetPixelColor(b.location.X, b.location.Y).ToString());
                    grid[b.location.X, b.location.Y] = (bikes.IndexOf(b) + 1);
                }

                foreach (LightBike b in bikes) //update positions
                {
                    if(b.isBoosting && b.boostCounter > 0) //player is boosting
                    {
                        while(isValidLocation(b.getNextLocation()))
                        {
                            b.location = b.getNextLocation();
                            b.boostCounter--;
                            if (b.boostCounter == 0)
                            {
                                b.isBoosting = false;
                                b.boostCounter = 20;
                            }
                        }
                    }
                    b.location = b.getNextLocation();

                }

                Thread.Sleep(GAME_SPEED);

            }
            String endingString ="";
            foreach (LightBike b in bikes)
            {
                endingString += b.toColorString() + " ";
                if (gameStatus == "WIN")
                    b.score += 1;    
            }


            endingString += gameStatus+"!";
            canvas.DrawString(endingString,new Font("Times New Roman",20),new SolidBrush(Color.White),new Point(150,200));


            firststart = false;
            drawThread.Abort();

        }

Answer 1

取而代之的是:

public void SetLabel(string message)
{

    if (this.textBox1.InvokeRequired)
        this.textBox1.Invoke((Action<string>)SetLabel, message);
    else
        this.textBox1.Text = message;
    MessageBox.Show(message); 
}

只需这样做:

public void SetLabel(string message)
{
    // processing things here


    this.Invoke((MethodInvoker)delegate
    {
        // UI things here

        this.textBox1.Text = message;
    });


    MessageBox.Show(message);   
}    

这样，您就不需要不断地检测 InvokeRequired