Question

我正在为学校做一个tictactoe项目，我似乎无法解决我无法访问的代码问题。我查找了其他无法访问的代码问题，但我不确定如何解决它，因为我不是很擅长这个。我知道这是一个警告，但当我开始我的程序时，它不会填写空白当我按他们。

    private void Movement(object sender, EventArgs e)
    {
        if (InvokeRequired)
        {
            this.Invoke(new Action<object, EventArgs>(Movement), new object[] { sender, e });
            return;
            UpdateData(sender); //This is where it points for unreachable
            var lbl = (Label)sender;
            lbl.Enabled = false;
            lbl.Text = currentPlayer.ToString();
            if (!CheckWin())
                NextTurn();

        }
    }
    private void UpdateData(object sender)
        {
            Label lbl = sender as Label;
            if (lbl == lbl00)
                GameData[0, 0] = currentPlayer;
            else if (lbl == lbl10)
                GameData[1, 0] = currentPlayer;
            else if (lbl == lbl20)
                GameData[2, 0] = currentPlayer;
            else if (lbl == lbl01)
                GameData[0,1] = currentPlayer;
            else if (lbl == lbl11)
                GameData[1, 1] = currentPlayer;
            else if (lbl == lbl21)
                GameData[2, 1] = currentPlayer;
            else if (lbl == lbl02)
                GameData[0, 2] = currentPlayer;
            else if (lbl == lbl12)
                GameData[1, 2] = currentPlayer;
            else if (lbl == lbl22)
                GameData[2, 2] = currentPlayer;
        }

Answer 1

因为您在return行之后加this.Invoke(new Action<object, EventArgs>(Movement), new object[] { sender, e });所以其他行无法访问

Answer 2

只是为了添加更明显的答案，您还没有正确实现"Invoke on UI Thread"模式。您需要使用额外的else分支替换返回：

private void Movement(object sender, EventArgs e)
{
    if (InvokeRequired)
    {
        // Oops, we're not on the UI thread. Invoke on the UI thread.
        this.Invoke(new Action<object, EventArgs>(Movement), new object[] { sender, e });
        ... nasty exceptions happen if you try and update UI controls on a non-UI thread
    }
    else
    {
        // Now we're on the UI thread
        UpdateData(sender);
        ... clear to interact with UI controls.
    }
}

虽然你也可以使用return重构代码以尽早退出非UI线程分支，然后删除else。

private void Movement(object sender, EventArgs e)
{
    if (InvokeRequired)
    {
        // Oops, we're not on the UI thread. Invoke on the UI thread.
        this.Invoke(new Action<object, EventArgs>(Movement), new object[] { sender, e });
        return; // i.e. exit the method here from this non UI thread branch
    }
    // We are now on the UI thread ...
    UpdateData(sender);
    ...
}

“检测到无法访问的代码”我已经查看了其他无法访问的代码，但我似乎无法修复我的问题，停下来

2 个答案: