C# · 12月 29, 2021

C#实现listview Group收缩扩展的方法

本文实例讲述了C#实现listview Group收缩扩展的方法。分享给大家供大家参考,具体如下:

1、本实例是完善了codeprofect上面charju老师“Add Group Collapse Behavior on a Listview Control”的一个限制(点击分组后面的图标不能收缩和扩展);

2、本实列适用于win2008,vista;

3、仅供参考,如有更好的方法,望大家不吝交流~

完整代码如下(只需建一个windows工程,在窗体上拖一个listview控件,取名为aoc,右击编辑代码,把下面的代码粘到窗口就可以了~,但需要注意事件对应):

using System;using System.Collections.Generic;using System.ComponentModel;using System.Data;using System.Drawing;using System.Text;using System.Windows.Forms;using System.Runtime.InteropServices;using System.Diagnostics;namespace ListViewGroup{ public partial class MainForm : Form { public MainForm() { InitializeComponent(); } [DllImport(“user32.dll”)] static extern int SendMessage(IntPtr window,int message,int wParam,ref LVHITTESTINFO lParam); [DllImport(“user32.dll”)] static extern int SendMessage(IntPtr window,IntPtr lParam); private void btCollapse_Click(object sender,EventArgs e) { SetGroupCollapse(GroupState.COLLAPSED | GroupState.COLLAPSIBLE); } private void btExpand_Click(object sender,EventArgs e) { SetGroupCollapse(GroupState.EXPANDED | GroupState.COLLAPSIBLE); } private void SetGroupCollapse(GroupState state) { for (int i = 0; i <= aoc.Groups.Count; i++) { LVGROUP group = new LVGROUP(); group.cbSize = Marshal.SizeOf(group); group.state = (int)state; // LVGS_COLLAPSIBLE group.mask = 4; // LVGF_STATE group.iGroupId = i; IntPtr ip = IntPtr.Zero; try { ip = Marshal.AllocHGlobal(group.cbSize); Marshal.StructureToPtr(group,ip,true); SendMessage(aoc.Handle,0x1000 + 147,i,ip); // #define LVM_SETGROUPINFO (LVM_FIRST + 147) } catch (Exception ex) { System.Diagnostics.Trace.WriteLine(ex.Message + Environment.NewLine + ex.StackTrace); } finally { if (null != ip) Marshal.FreeHGlobal(ip); } } } private void MainForm_Load(object sender,EventArgs e) { SetGroupCollapse(GroupState.COLLAPSIBLE); for (int i = 0; i < aoc.Groups.Count; i++) { aoc.Groups[i].Tag = “EXPANDED”; } } private void aoc_MouseDown(object sender,MouseEventArgs e) { LVHITTESTINFO lvHitInfo = new LVHITTESTINFO(); Point p = new Point(e.X,e.Y); lvHitInfo.pt = p; try { int id = SendMessage(aoc.Handle,0x1000 + 18,-1,ref lvHitInfo); if (lvHitInfo.flags == 0x50000000) { if (aoc.Groups[id].Tag.ToString() ==”EXPANDED”) { SetGroupCollapseEx(id,GroupState.COLLAPSED | GroupState.COLLAPSIBLE); aoc.Groups[id].Tag = “COLLAPSED”; } else if ( aoc.Groups[id].Tag.ToString() == “COLLAPSED”) { SetGroupCollapseEx(id,GroupState.EXPANDED | GroupState.COLLAPSIBLE); aoc.Groups[id].Tag = “EXPANDED”; } } //Message@R_624_2419@.Show(string.Format(“RESULT={0} FLAGS=0x{1:X}”,id,lvHitInfo.flags)); } catch (Exception ex) { Trace.WriteLine(ex.Message + Environment.NewLine + ex.StackTrace); } finally { ; } } private void SetGroupCollapseEx(int id,GroupState groupState) { int i = id; LVGROUP group = new LVGROUP(); group.cbSize = Marshal.SizeOf(group); group.state = (int)groupState; // LVGS_COLLAPSIBLE group.mask = 4; // LVGF_STATE group.iGroupId = i; IntPtr ip = IntPtr.Zero; try { ip = Marshal.AllocHGlobal(group.cbSize); Marshal.StructureToPtr(group,true); SendMessage(aoc.Handle,ip); // #define LVM_SETGROUPINFO (LVM_FIRST + 147) } catch (Exception ex) { System.Diagnostics.Trace.WriteLine(ex.Message + Environment.NewLine + ex.StackTrace); } finally { if (null != ip) Marshal.FreeHGlobal(ip); } } } [StructLayout(LayoutKind.Sequential)] public struct LVGROUP { public int cbSize; public int mask; [MarshalAs(UnmanagedType.LPTStr)] public string pszHeader; public int cchHeader; [MarshalAs(UnmanagedType.LPTStr)] public string pszFooter; public int cchFooter; public int iGroupId; public int stateMask; public int state; public int uAlign; } public enum GroupState { COLLAPSIBLE = 8,COLLAPSED = 1,EXPANDED = 0 } [StructLayout(LayoutKind.Sequential)] public struct LVHITTESTINFO { public Point pt; public int flags; public int iItem; public int iSubItem; public int iGroup; }}

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希望本文所述对大家C#程序设计有所帮助。