TableLayoutPanel 更新滞后

Question

我有一个 WinForms 应用程序，它正在从 BackgroundWorker 更新 TableLayoutPanel。根据设备输入是打开 (1) 还是关闭 (0)，颜色和一些文本会相应更改。

try
{
    //Define a new TLP to hold the search tablelayoutpanel. 
    //search for the iterated card number.
    //get the status label using GetControl from Position.
    TableLayoutPanel TLP = new TableLayoutPanel();
    string IO_Card_Name = "ED527_" + i.ToString();
    TLP = TLP_IO_Info.Controls.Find(IO_Card_Name, true).FirstOrDefault() as TableLayoutPanel;
    try { lbl = TLP.GetControlFromPosition(4, 0) as Label; } catch { lbl = null; };
    //if card is found (because input is active, colour the TLP (card) according to its state.
    if (TLP != null && lbl != null && INPUTS[i - 1] == 1)
    {

        TLP.BackColor = Color.Green;

        foreach (Label l in TLP.Controls)
        {
            l.BackColor = Color.Green;
        }
        lbl.Invoke((MethodInvoker)delegate { lbl.Text = "ON"; });
    }
    else if (TLP != null && lbl != null && INPUTS[i - 1] == 0)
    {
        TLP.BackColor = Color.White;
        foreach (Label l in TLP.Controls)
        {
            l.BackColor = Color.White;
        }
        lbl.Invoke((MethodInvoker)delegate { lbl.Text = "OFF"; });
    }
}
catch (Exception exception)
{
    MessageBox.Show(exception.Message);
};

TLP 包含 5 个标签。当线路更新时，更新显示出一些明显的滞后。有没有办法可以在主 UI 线程上执行类似于 SuspendLayout() / ResumeLayout 的操作？

****EDIT 显示之前和之后 - IOLabel 列在 Status 列之前稍稍更新。

Answer 1

听起来你有一个嵌套设计。每行是 5 个标签，由不同的 TableLayoutPanel 托管，TLP_IO_Info 是 TableLayoutPanel 托管其他 TableLayoutPanel。在 BackgroundWorker 的 DoWork 事件中，您有一个 for..loop 以根据您从 INPUT int 读取的设备的当前 state 更改内部控件的 Backcolor大批。请纠正我。

我想建议这个：

foreach (var tlp in TLP_IO_Info.Controls.OfType<TableLayoutPanel>()
    .Where(x => x.Name.StartsWith("ED527_")))
{
    if (tlp.GetControlFromPosition(4, 0) is Label lbl)
    {
        var state = // get the state of the current device from INPUT array
        var stateColor = state == 1 ? Color.Green : Color.White;
        var stateText = state == 1 ? "ON" : "OFF";
        this.Invoke(new Action(() =>
        {
            tlp.BackColor = stateColor;
            tlp.Controls.OfType<Label>().ToList().ForEach(l => l.BackColor = stateColor);
            lbl.Text = stateText;
        }));                        
    }
}

或者这样消除冗余代码：

var stateColors = new[] { Color.White, Color.Green };
var stateTexts = new[] { "OFF", "ON" };

foreach (var tlp in TLP_IO_Info.Controls.OfType<TableLayoutPanel>()
    .Where(x => x.Name.StartsWith("ED527_")))
{
    if (tlp.GetControlFromPosition(4, 0) is Label lbl)
    {
        var state = // get the state of the current device from INPUT array
        this.Invoke(new Action(() =>
        {
            tlp.BackColor = stateColors[state];
            tlp.Controls.OfType<Label>().ToList()
            .ForEach(l => l.BackColor = stateColors[state]);
            lbl.Text = stateTexts[state];
        }));
    }
}

请注意，我已删除昂贵的 try..catch 块，因为此代码不会引发任何异常。

至于INPUT 数组，我建议您将其替换为Dictionary<string, int> 以存储每个设备的当前状态，因为（根据您提供的链接）每个设备都有一个唯一的IOLineNumber 所以您可以轻松设置/获取每个的当前状态。

^{⍰也许图书馆里已经有类似的东西了？}