Csharp 如何在C#.NET桌面应用程序中动态更改焦点工具上的后退 colored颜色

发布于11月27日

在我的桌面窗体中有许多控件.一旦失go 焦点，我想将Focus&amp；上的活动控件的 colored颜色改回原来的 colored颜色 .

这是我的代码，

public BillingMetal(Billing _frm)
{
    this.frm = _frm;
    InitializeComponent();

    foreach (Control ctrl in this.Controls)
    {
        ctrl.GotFocus += ctrl_GotFocus;
        ctrl.LostFocus += ctrl_LostFocus;
    }
}

public void ctrl_LostFocus(object sender, EventArgs e)
{
    var ctrl = sender as Control;
    if (ctrl.Tag is Color)
        ctrl.BackColor = (Color)ctrl.Tag;
}

public void ctrl_GotFocus(object sender, EventArgs e)
{
    var ctrl = sender as Control;
    ctrl.Tag = ctrl.BackColor;
    ctrl.BackColor = Color.Red;
}

Actually this code is working but for the button only not for textbox, combobox or any other tools.个

推荐答案

您的代码看起来基本没问题，但您需要确保同时迭代了Control树的所有子级(所有子级...).

public partial class BillingMetal : Form
{
    public BillingMetal()
    {
        InitializeComponent();
        foreach (var ctrl in IterateControls(Controls))
        {
            ctrl.GotFocus += (sender, e) =>
            { 
                if(sender is Control ctrl)
                {
                    ctrl.Tag = ctrl.BackColor;
                    ctrl.BackColor = Color.Red;
                }
            };
            ctrl.LostFocus += (sender, e) =>
            {
                if(sender is Control ctrl && ctrl.Tag is Color color)
                {
                    ctrl.BackColor = color;
                }
            };
        }
    }

Iterator个

    IEnumerable<Control> IterateControls(Control.ControlCollection controls)
    {
        foreach (Control control in controls)
        {
            yield return control;
            foreach (Control child in IterateControls(control.Controls))
            {
                yield return child;
            }
        }
    }
}