如何使用 C# 在列表视图列的标题中显示排序箭头？

How to I display a sort arrow in the header of a list view column using C#?

提问by Andrew Moore

How can I display a sort arrow in the header of the sorted column in a list view which follows the native look of the operating system?

如何在遵循操作系统本机外观的列表视图中在排序列的标题中显示排序箭头？

采纳答案by Andrew Moore

You can use the following extension method to set the sort arrow to a particular column:

您可以使用以下扩展方法将排序箭头设置为特定列：

[EditorBrowsable(EditorBrowsableState.Never)]
public static class ListViewExtensions
{
    [StructLayout(LayoutKind.Sequential)]
    public struct HDITEM
    {
        public Mask mask;
        public int cxy;
        [MarshalAs(UnmanagedType.LPTStr)] public string pszText;
        public IntPtr hbm;
        public int cchTextMax;
        public Format fmt;
        public IntPtr lParam;
        // _WIN32_IE >= 0x0300 
        public int iImage;
        public int iOrder;
        // _WIN32_IE >= 0x0500
        public uint type;
        public IntPtr pvFilter;
        // _WIN32_WINNT >= 0x0600
        public uint state;

        [Flags]
        public enum Mask
        {
            Format = 0x4,       // HDI_FORMAT
        };

        [Flags]
        public enum Format
        {
            SortDown = 0x200,   // HDF_SORTDOWN
            SortUp = 0x400,     // HDF_SORTUP
        };
    };

    public const int LVM_FIRST = 0x1000;
    public const int LVM_GETHEADER = LVM_FIRST + 31;

    public const int HDM_FIRST = 0x1200;
    public const int HDM_GETITEM = HDM_FIRST + 11;
    public const int HDM_SETITEM = HDM_FIRST + 12;

    [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
    public static extern IntPtr SendMessage(IntPtr hWnd, UInt32 msg, IntPtr wParam, IntPtr lParam);

    [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
    public static extern IntPtr SendMessage(IntPtr hWnd, UInt32 msg, IntPtr wParam, ref HDITEM lParam);

    public static void SetSortIcon(this ListView listViewControl, int columnIndex, SortOrder order)
    {
        IntPtr columnHeader = SendMessage(listViewControl.Handle, LVM_GETHEADER, IntPtr.Zero, IntPtr.Zero);
        for (int columnNumber = 0; columnNumber <= listViewControl.Columns.Count - 1; columnNumber++)
        {
            var columnPtr = new IntPtr(columnNumber);
            var item = new HDITEM
                {
                    mask = HDITEM.Mask.Format
                };

            if (SendMessage(columnHeader, HDM_GETITEM, columnPtr, ref item) == IntPtr.Zero)
            {
                throw new Win32Exception();
            }

            if (order != SortOrder.None && columnNumber == columnIndex)
            {
                switch (order)
                {
                    case SortOrder.Ascending:
                        item.fmt &= ~HDITEM.Format.SortDown;
                        item.fmt |= HDITEM.Format.SortUp;
                        break;
                    case SortOrder.Descending:
                        item.fmt &= ~HDITEM.Format.SortUp;
                        item.fmt |= HDITEM.Format.SortDown;
                        break;
                }
            }
            else
            {
                item.fmt &= ~HDITEM.Format.SortDown & ~HDITEM.Format.SortUp;
            }

            if (SendMessage(columnHeader, HDM_SETITEM, columnPtr, ref item) == IntPtr.Zero)
            {
                throw new Win32Exception();
            }
        }
    }
}

Then, you can call the extension method like such:

然后，您可以像这样调用扩展方法：

myListView.SetSortIcon(0, SortOrder.Ascending);

It works by using P/Invoke to:

它通过使用 P/Invoke 来工作：

• Get the handle to the header control for a list view using the LVM_GETHEADERmessage.
• Get the information about a header column using the HDM_GETITEMmessage.
• It then modifies the fmtto set / clear the HDF_SORTDOWNand HDF_SORTUPflags on the returned HDITEMstructure.
• Finally it re-sets the information usintg the HDM_SETITEMmessage.

• 使用LVM_GETHEADER消息获取列表视图的标题控件的句柄。
• 使用HDM_GETITEM消息获取有关标题列的信息。
• 然后修改fmt设置/清除返回的HDITEM结构上的HDF_SORTDOWN和HDF_SORTUP标志。
• 最后，它使用HDM_SETITEM消息重新设置信息。

This is what it looks like:

这是它的样子：

回答by Jesse

Great answer by Andrew. If Anyone is looking for the VB.net equivalent here it is:

安德鲁很好的回答。如果有人在这里寻找 VB.net 等效项，它是：

Public Module ListViewExtensions
    Public Enum SortOrder
        None
        Ascending
        Descending
    End Enum

    <StructLayout(LayoutKind.Sequential)>
    Public Structure HDITEM
        Public theMask As Mask
        Public cxy As Integer
        <MarshalAs(UnmanagedType.LPTStr)>
        Public pszText As String
        Public hbm As IntPtr
        Public cchTextMax As Integer
        Public fmt As Format
        Public lParam As IntPtr
        ' _WIN32_IE >= 0x0300 
        Public iImage As Integer
        Public iOrder As Integer
        ' _WIN32_IE >= 0x0500
        Public type As UInteger
        Public pvFilter As IntPtr
        ' _WIN32_WINNT >= 0x0600
        Public state As UInteger

        <Flags()>
        Public Enum Mask
            Format = &H4       ' HDI_FORMAT
        End Enum


        <Flags()>
        Public Enum Format
            SortDown = &H200 ' HDF_SORTDOWN
            SortUp = &H400     ' HDF_SORTUP
        End Enum
    End Structure

    Public Const LVM_FIRST As Integer = &H1000
    Public Const LVM_GETHEADER As Integer = LVM_FIRST + 31

    Public Const HDM_FIRST As Integer = &H1200
    Public Const HDM_GETITEM As Integer = HDM_FIRST + 11
    Public Const HDM_SETITEM As Integer = HDM_FIRST + 12

    <DllImport("user32.dll", CharSet:=CharSet.Auto, SetLastError:=True)>
    Public Function SendMessage(hWnd As IntPtr, msg As UInt32, wParam As IntPtr, lParam As IntPtr) As IntPtr
    End Function

    <DllImport("user32.dll", CharSet:=CharSet.Auto, SetLastError:=True)>
    Public Function SendMessage(hWnd As IntPtr, msg As UInt32, wParam As IntPtr, ByRef lParam As HDITEM) As IntPtr
    End Function

    <Extension()>
    Public Sub SetSortIcon(listViewControl As ListView, columnIndex As Integer, order As SortOrder)
        Dim columnHeader As IntPtr = SendMessage(listViewControl.Handle, LVM_GETHEADER, IntPtr.Zero, IntPtr.Zero)
        For columnNumber As Integer = 0 To listViewControl.Columns.Count - 1

            Dim columnPtr As New IntPtr(columnNumber)
            Dim item As New HDITEM

            item.theMask = HDITEM.Mask.Format

            If SendMessage(columnHeader, HDM_GETITEM, columnPtr, item) = IntPtr.Zero Then Throw New Win32Exception

            If order <> SortOrder.None AndAlso columnNumber = columnIndex Then
                Select Case order
                    Case SortOrder.Ascending
                        item.fmt = item.fmt And Not HDITEM.Format.SortDown
                        item.fmt = item.fmt Or HDITEM.Format.SortUp
                    Case SortOrder.Descending
                        item.fmt = item.fmt And Not HDITEM.Format.SortUp
                        item.fmt = item.fmt Or HDITEM.Format.SortDown
                End Select
            Else
                item.fmt = item.fmt And Not HDITEM.Format.SortDown And Not HDITEM.Format.SortUp
            End If

            If SendMessage(columnHeader, HDM_SETITEM, columnPtr, item) = IntPtr.Zero Then Throw New Win32Exception
        Next
    End Sub
End Module

回答by Mordachai

For any other lazy C++ programmers (like me):

对于任何其他懒惰的 C++ 程序员（如我）：

// possible sorting header icons / indicators
enum class ListViewSortArrow { None, Ascending, Descending };

BOOL LVHeader_SetSortArrow(HWND hHeader, int nColumn, ListViewSortArrow sortArrow)
{
    ASSERT(hHeader);

    HDITEM hdrItem = { 0 };
    hdrItem.mask = HDI_FORMAT;
    if (Header_GetItem(hHeader, nColumn, &hdrItem))
    {
        switch (sortArrow)
        {
        default:
            ASSERT(false);
        case ListViewSortArrow::None:
            hdrItem.fmt = hdrItem.fmt & ~(HDF_SORTDOWN | HDF_SORTUP);
            break;
        case ListViewSortArrow::Ascending:
            hdrItem.fmt = (hdrItem.fmt & ~HDF_SORTDOWN) | HDF_SORTUP;
            break;
        case ListViewSortArrow::Descending:
            hdrItem.fmt = (hdrItem.fmt & ~HDF_SORTUP) | HDF_SORTDOWN;
            break;
        }

        return Header_SetItem(hHeader, nColumn, &hdrItem);
    }

    return FALSE;
}

BOOL ListView_SetSortArrow(HWND hListView, int nColumn, ListViewSortArrow sortArrow)
{
    ASSERT(hListView);

    if (HWND hHeader = ListView_GetHeader(hListView))
        return LVHeader_SetSortArrow(hHeader, nColumn, sortArrow);

    return FALSE;
}

回答by symbiont

instead of messing with the Windows API, you can compromise and use characters that look like arrows (i picked them using charmap)

您可以妥协并使用看起来像箭头的字符，而不是弄乱 Windows API（我使用 charmap 选择它们）

private void SetSortArrow(ColumnHeader head, SortOrder order)
{
    const string ascArrow = " ▲";
    const string descArrow = " ▼";

    // remove arrow
    if(head.Text.EndsWith(ascArrow) || head.Text.EndsWith(descArrow))
        head.Text = head.Text.Substring(0, head.Text.Length-2);

    // add arrow
    switch (order)
    {
        case SortOrder.Ascending: head.Text += ascArrow; break;
        case  SortOrder.Descending: head.Text += descArrow; break;
    }
}

SetSortArrow(listView1.Columns[0], SortOrder.None);       // remove arrow from first column if present
SetSortArrow(listView1.Columns[1], SortOrder.Ascending);  // set second column arrow to ascending
SetSortArrow(listView1.Columns[1], SortOrder.Descending); // set second column arrow to descending