是否将“全选”快捷方式(Ctrl+a)添加到.net listview?

您可以通过以下方式实现这两个目标:

private void listView1_KeyDown(object sender, KeyEventArgs e)
{
    if (e.KeyCode == Keys.A && e.Control)
    {
        listView1.MultiSelect = true;
        foreach (ListViewItem item in listView1.Items)
        {
            item.Selected = true;
        }
    }
}

这些方法适用于小列表,但如果虚拟列表中有100000个项目,这可能需要很长时间。这可能是出于您的目的,但以防万一:

class NativeMethods {
    private const int LVM_FIRST = 0x1000;
    private const int LVM_SETITEMSTATE = LVM_FIRST + 43;

    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)]
    public struct LVITEM
    {
        public int mask;
        public int iItem;
        public int iSubItem;
        public int state;
        public int stateMask;
        [MarshalAs(UnmanagedType.LPTStr)]
        public string pszText;
        public int cchTextMax;
        public int iImage;
        public IntPtr lParam;
        public int iIndent;
        public int iGroupId;
        public int cColumns;
        public IntPtr puColumns;
    };

    [DllImport("user32.dll", EntryPoint = "SendMessage", CharSet = CharSet.Auto)]
    public static extern IntPtr SendMessageLVItem(IntPtr hWnd, int msg, int wParam, ref LVITEM lvi);

    /// <summary>
    /// Select all rows on the given listview
    /// </summary>
    /// <param name="list">The listview whose items are to be selected</param>
    public static void SelectAllItems(ListView list) {
        NativeMethods.SetItemState(list, -1, 2, 2);
    }

    /// <summary>
    /// Deselect all rows on the given listview
    /// </summary>
    /// <param name="list">The listview whose items are to be deselected</param>
    public static void DeselectAllItems(ListView list) {
        NativeMethods.SetItemState(list, -1, 2, 0);
    }

    /// <summary>
    /// Set the item state on the given item
    /// </summary>
    /// <param name="list">The listview whose item's state is to be changed</param>
    /// <param name="itemIndex">The index of the item to be changed</param>
    /// <param name="mask">Which bits of the value are to be set?</param>
    /// <param name="value">The value to be set</param>
    public static void SetItemState(ListView list, int itemIndex, int mask, int value) {
        LVITEM lvItem = new LVITEM();
        lvItem.stateMask = mask;
        lvItem.state = value;
        SendMessageLVItem(list.Handle, LVM_SETITEMSTATE, itemIndex, ref lvItem);
    }
}

你是这样用的::

NativeMethods.SelectAllItems(this.myListView);

private void listView1_KeyDown(object sender, KeyEventArgs e)
{
    if (e.KeyData == (Keys.A | Keys.Control))
        foreach (ListViewItem item in listView1.Items)
            item.Selected = true;
}

到 只有

如果用户发布 Ctrl键 钥匙在前。

你应该使用 KeyDown 相反,事件:

private void listView1_KeyDown(object sender, KeyEventArgs e)
{
    if (e.KeyCode == Keys.A && e.Control)
    {
        listView1.MultiSelect = true;
        foreach (ListViewItem item in listView1.Items)
        {
            item.Selected = true;
        }
    }
}

我无法对第一个问题发表评论,但使用KeyDown的解决方案对我来说不起作用,因为系统会在按下LeftCtrl时立即做出反应,因此跳过CTRL+A。从另一面看,keydup可以正常工作。

private void listView1_KeyUp(object sender, KeyEventArgs e)
{
    if (e.KeyCode == Keys.A && e.Control)
    {
        listView1.MultiSelect = true;
        foreach (ListViewItem item in listView1.Items)
        {
            item.Selected = true;
        }
    }
}