自定义屏幕键盘和过滤下拉列表播放效果不佳

Question

在我的winforms应用程序中，我有一个自定义的屏幕十键键盘，除了一个带有自定义筛选代码的下拉列表外，它似乎在任何地方都能正常工作。我已经尽力让这个键盘在我能想象的各个方面都不具有交互功能。以下是后面的代码(numpad0、numpad1等都是标签，如果这很重要的话)

public partial class TenKeyForm : Form
{
private const int WM_NCLBUTTONDOWN = 0xA1;
private const int HT_CAPTION = 0x2;
private const int WM_MOUSEACTIVATE = 0x0021, MA_NOACTIVATE = 0x0003;
private const int WS_EX_NOACTIVATE = 0x08000000;
protected override bool ShowWithoutActivation { get { return true; } }
protected override void WndProc(ref Message m)
{
if (m.Msg == WM_MOUSEACTIVATE)
{
m.Result = (IntPtr)MA_NOACTIVATE;
return;
}
base.WndProc(ref m);
}
protected override CreateParams CreateParams
{
get
{
CreateParams createParams = base.CreateParams;
createParams.ExStyle |= WS_EX_NOACTIVATE;
return createParams;
}
}
[System.Runtime.InteropServices.DllImport("user32.dll")]
public static extern int SendMessage(IntPtr hWnd, int Msg, int wParam, int lParam);
[System.Runtime.InteropServices.DllImport("user32.dll")]
public static extern bool ReleaseCapture();
public TenKeyForm()
{
InitializeComponent();
MouseDown += MouseDownHandler;
numpad0.MouseUp += new MouseEventHandler(delegate (object o, MouseEventArgs e) { SendKeys.Send("0"); });
numpad1.MouseUp += new MouseEventHandler(delegate (object o, MouseEventArgs e) { SendKeys.Send("1"); });
numpad2.MouseUp += new MouseEventHandler(delegate (object o, MouseEventArgs e) { SendKeys.Send("2"); });
numpad3.MouseUp += new MouseEventHandler(delegate (object o, MouseEventArgs e) { SendKeys.Send("3"); });
numpad4.MouseUp += new MouseEventHandler(delegate (object o, MouseEventArgs e) { SendKeys.Send("4"); });
numpad5.MouseUp += new MouseEventHandler(delegate (object o, MouseEventArgs e) { SendKeys.Send("5"); });
numpad6.MouseUp += new MouseEventHandler(delegate (object o, MouseEventArgs e) { SendKeys.Send("6"); });
numpad7.MouseUp += new MouseEventHandler(delegate (object o, MouseEventArgs e) { SendKeys.Send("7"); });
numpad8.MouseUp += new MouseEventHandler(delegate (object o, MouseEventArgs e) { SendKeys.Send("8"); });
numpad9.MouseUp += new MouseEventHandler(delegate (object o, MouseEventArgs e) { SendKeys.Send("9"); });
numpadDot.MouseUp += new MouseEventHandler(delegate (object o, MouseEventArgs e) { SendKeys.Send("."); });
numpadBack.MouseUp += new MouseEventHandler(delegate (object o, MouseEventArgs e) { SendKeys.Send("+{TAB}"); });
numpadForward.MouseUp += new MouseEventHandler(delegate (object o, MouseEventArgs e) { SendKeys.Send("{TAB}"); });
numpadBackspace.MouseUp += new MouseEventHandler(delegate (object o, MouseEventArgs e) { SendKeys.Send("{BS}"); });
SetStyle(ControlStyles.Selectable, false);
}
private void MouseDownHandler(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
ReleaseCapture();
SendMessage(Handle, WM_NCLBUTTONDOWN, HT_CAPTION, 0);
}
}
}

同样，除了单个ComboBox之外，这对各种文本框、屏蔽输入等都很好。此组合框有一些额外的验证，以防止键入无效的选择。基本上，如果它有一个条目"500"one_answers"550"，键入"5"会跳到列表中的"500"，并将除了您键入的"5"之外的所有内容都高亮显示，以便下一次按键将替换它，即500。此时，它将拒绝除"5"或"0"之外的任何内容。键入另外5个突出显示550，依此类推

private void ValidateDropDown(object sender, KeyPressEventArgs e)
{
ToolStripComboBox tcb = (ToolStripComboBox)sender;
ComboBox cb = tcb.ComboBox;
cb.DroppedDown = true;
string strFindStr = "";
if (e.KeyChar == (char)8)
{
if (cb.SelectionStart <= 1)
{
cb.Text = "";
return;
}
if (cb.SelectionLength == 0)
strFindStr = cb.Text.Substring(0, cb.Text.Length - 1);
else
strFindStr = cb.Text.Substring(0, cb.SelectionStart - 1);
}
else
{
if (cb.SelectionLength == 0)
strFindStr = cb.Text + e.KeyChar;
else
strFindStr = cb.Text.Substring(0, cb.SelectionStart) + e.KeyChar;
}
int intIdx = -1;
// Search the string in the ComboBox list.
intIdx = cb.FindString(strFindStr);
if (intIdx != -1)
{
cb.SelectedText = "";
cb.SelectedIndex = intIdx;
cb.SelectionStart = strFindStr.Length;
cb.SelectionLength = cb.Text.Length;
e.Handled = true;
}
else
e.Handled = true;
}

现在十键在任何地方都可以工作，但这个组合框，如果你用实际键盘打字，这个组合框也可以完美工作。屏幕键盘甚至可以在第一次按键时正常工作，但tenkey窗体上的任何后续鼠标按下事件似乎都会在ComboBox上执行类似SelectAll()的操作，从而否定精心设置的选择。在上例中键入"55"不会导航到550，而是导航到500两次，每次单击都会替换整个文本。

是什么导致了这种奇怪的行为？我该如何阻止它？

更新：这似乎是ToolStrip组合框特有的问题，应该考虑将其包含在此处。另外：AutoCompleteMode=AutoCompleteMode。建议附加

Answer 1

如何设置AutoCompleteMode？

我做了测试，并设置它：

AutoCompleteMode = AutoCompleteMode.Suggest;

解决了所描述的问题。

编辑1

我已经找到了解决这个问题的方法，你可以添加：

toolStripComboBox1.SelectionLength=0;

在CCD_ 7功能之前。