Deverpress7.1中没有ShowCheckBox属性时的实现办法

来源：互联网发布：手环值得买吗知乎编辑：程序博客网时间：2024/06/06 07:06

一、TreeList的GetStateImage事件应用。

///private void treeList_GetStateImage(object sender, DevExpress.XtraTreeList.GetStateImageEventArgs e){   CheckState check = GetCheckState(e.Node.Tag);   if(check == CheckState.Unchecked)    e.NodeImageIndex = 0; ///////"0"为没有勾的图标   else if(check == CheckState.Checked)    e.NodeImageIndex = 1;   else e.NodeImageIndex = 2;}///

方法二：为tree中指定的节点区分现实不同的图片。
事例代码如下：

///

private void roleTree_GetStateImage(object sender, DevExpress.XtraTreeList.GetStateImageEventArgs e)        {            if(e.Node.Id.ToString() == "0")            {                this.roleTree.Nodes[0].RootNode.StateImageIndex = 1;            }            else            {                e.NodeImageIndex = 0;            }        }

二、TreeList中运用MouseDown事件获取所选节点信息。
提取tree中的值所用事件为MouseDown，在事件中填写如下代码

///

private void roleTree_MouseDown(object sender, System.Windows.Forms.MouseEventArgs e)        {            if(e.Button == MouseButtons.Left)            {                DevExpress.XtraTreeList.TreeListHitInfo hInfo = roleTree.GetHitInfo(new Point(e.X, e.Y));                if(hInfo.HitInfoType == DevExpress.XtraTreeList.HitInfoType.StateImage)                {                    if(MessageBox.Show("你确定要删除"+hInfo.Node[1].ToString()+"角色","提示信息",MessageBoxButtons.YesNo,MessageBoxIcon.Question)==DialogResult.Yes)                    {                        TB_Accounts_RolesEntity role = new TB_Accounts_RolesEntity();                        role.iRoleID = Convert.ToInt32(hInfo.Node[1].ToString());                        role.Retrieve();                        role.Delete();                        InitRoleTree();                    }                    else                    {}                }                else if(hInfo.HitInfoType == DevExpress.XtraTreeList.HitInfoType.Cell)                {                    //得到指定iRoleID的全部的vDescript的允许的Table                    string roleID = hInfo.Node[1].ToString();                    string sqlString="SELECT dbo.TB_Accounts_Permissions.vDescript FROM dbo.TB_Accounts_Permissions INNER JOIN dbo.TB_Accounts_RolePermissions ON dbo.TB_Accounts_Permissions.iPermissionID = dbo.TB_Accounts_RolePermissions.iPermissionID WHERE 1=1"; //编写SQL语句                    sqlString +=" and dbo.TB_Accounts_RolePermissions.iRoleID = '"+roleID+"'";                    //执行SQL语句                    DataTable dt=Query.ProcessSql(sqlString,"EasySales");                    for(int i = 0; i<dt.Rows.Count; i++)                    {                        string treeText = treeList.GetNodeByVisibleIndex(i).GetDisplayText(0).ToString();                        if(treeText == dt.Rows[i]["vDescript"].ToString())                        {                            SetCheckedNode(treeList.Nodes[0].Nodes[i]);                        }                                                    }                }            }        }

三、TreeList前添加CheckBox的选择框，可实现点击父节点相应子节点全部选中的效果。
TreeList中并为提供对应实现此功能的CheckBox自定义列，故必须用上面提到的GetStateImage事件添加三个（全选、部分全选、为选中）CheckBox的图片，具体样式可自己设计，然后放到窗体中的ImageList中去，触发及调用用到下面的代码：

//

private CheckState GetCheckState(object obj)        {            if(obj != null) return (CheckState)obj;            return CheckState.Unchecked;        }        private void SetCheckedNode(string treeText)        {            CheckState check = new CheckState();            check = CheckState.Checked;        }        private void SetCheckedNode(DevExpress.XtraTreeList.Nodes.TreeListNode node)        {            CheckState check = GetCheckState(node.Tag);            if(check == CheckState.Indeterminate || check == CheckState.Unchecked) check = CheckState.Checked;            else check = CheckState.Unchecked;            treeList.BeginUpdate();            node.Tag = check;            SetCheckedChildNodes(node, check);            SetCheckedParentNodes(node, check);            treeList.EndUpdate();        }        private void SetCheckedChildNodes(DevExpress.XtraTreeList.Nodes.TreeListNode node, CheckState check)        {            for(int i = 0; i < node.Nodes.Count; i++)            {                node.Nodes[i].Tag = check;                SetCheckedChildNodes(node.Nodes[i], check);            }        }        private void SetCheckedParentNodes(DevExpress.XtraTreeList.Nodes.TreeListNode node, CheckState check)        {            if(node.ParentNode != null)            {                bool b = false;                for(int i = 0; i < node.ParentNode.Nodes.Count; i++)                {                    if(!check.Equals(node.ParentNode.Nodes[i].Tag))                    {                        b = !b;                        break;                    }                }                node.ParentNode.Tag = b ? CheckState.Indeterminate : check;                SetCheckedParentNodes(node.ParentNode, check);            }        }        private void treeList_GetStateImage(object sender, DevExpress.XtraTreeList.GetStateImageEventArgs e)        {            CheckState check = GetCheckState(e.Node.Tag);            if(check == CheckState.Unchecked)                e.NodeImageIndex = 0;            else if(check == CheckState.Checked)                e.NodeImageIndex = 1;            else e.NodeImageIndex = 2;        }        private void treeList_KeyDown(object sender, System.Windows.Forms.KeyEventArgs e)        {            if(e.KeyData == Keys.Space)                SetCheckedNode(treeList.FocusedNode);        }        private void treeList_MouseDown(object sender, System.Windows.Forms.MouseEventArgs e)        {            if(e.Button == MouseButtons.Left)            {                DevExpress.XtraTreeList.TreeListHitInfo hInfo = treeList.GetHitInfo(new Point(e.X, e.Y));                if(hInfo.HitInfoType == DevExpress.XtraTreeList.HitInfoType.StateImage)                    SetCheckedNode(hInfo.Node);            }        }        private void roleTree_GetStateImage(object sender, DevExpress.XtraTreeList.GetStateImageEventArgs e)        {            if(e.Node.Id.ToString() == "0")            {                this.roleTree.Nodes[0].RootNode.StateImageIndex = 1;            }            else            {                e.NodeImageIndex = 0;            }        }

O了！！！

说明：那三张图片为在Dev的例子中可以找到……