C# TreeView 自定义显示checkbox

本项目需要对TreeView进行定制，要求比较简单，主要要求如下：

1. Winform中TreeView控件默认只支持所有级别的CheckBox显示或者不显示，不能控制制定Level的树节点显示

效果如下：

效果实现代码：

(1)属性和事件设置

this.treeViewGroupStatements.CheckBoxes = true;
this.treeViewGroupStatements.DrawMode = TreeViewDrawMode.OwnerDrawAll;
this.treeViewGroupStatements.DrawNode+=new DrawTreeNodeEventHandler(treeViewGroupStatements_DrawNode);

(2)实现代码

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#region 隐藏CheckBoxs  //要隐藏的TreeNode的level public ArrayList HideLevelList = new ArrayList() { 0, 1 }; private void treeViewGroupStatements_DrawNode(object sender, DrawTreeNodeEventArgs e) {     HideLevelOfTreeView(e.Node);     e.DrawDefault = true;   } private void HideLevelOfTreeView(TreeNode tn) {     //控制这个条件可以自定义显示checkbox的条件     if (HideLevelList.Contains(tn.Level))         HideCheckBox(tn.TreeView, tn); }   //#endregion     private const int TVIF_STATE = 0x8; private const int TVIS_STATEIMAGEMASK = 0xF000; private const int TV_FIRST = 0x1100; private const int TVM_SETITEM = TV_FIRST + 63; private void HideCheckBox(TreeView tvw, TreeNode node) {       TVITEM tvi = new TVITEM();       tvi.hItem = node.Handle;       tvi.mask = TVIF_STATE;       tvi.stateMask = TVIS_STATEIMAGEMASK;       tvi.state = 0;       SendMessage(tvw.Handle, TVM_SETITEM, IntPtr.Zero, ref tvi);   }   [StructLayout(LayoutKind.Sequential, Pack = 8, CharSet = CharSet.Auto)]   private struct TVITEM {     public int mask;     public IntPtr hItem;     public int state;     public int stateMask;     [MarshalAs(UnmanagedType.LPTStr)]     public string lpszText;     public int cchTextMax;     public int iImage;     public int iSelectedImage; public int cChildren; public IntPtr lParam; }   [DllImport("user32.dll", CharSet = CharSet.Auto)] private static extern IntPtr SendMessage(IntPtr hWnd, int Msg, IntPtr wParam, ref TVITEM lParam); #endregion