DevExpress的TreeList怎样给树节点设置图标

场景

DevExpress的TreeList怎样设置数据源使其显示成单列树形结构：

https://blog.csdn.net/BADAO_LIUMANG_QIZHI/article/details/102742426

在上面设置TreeList的数据源并设置其为树形结构后，如何给树形结构设置图标

注：

博客主页：
https://blog.csdn.net/badao_liumang_qizhi
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实现

首先按照上面搭建好树形结构和设置数据源之后效果如下

然后在项目下新建Resources目录，将图标文件复制进去

然后在窗体类中获取图标数组

 public static System.Drawing.Image[] imgs = new System.Drawing.Image[] { 
            System.Drawing.Image.FromFile(@"../../Resources/a.png"),
            System.Drawing.Image.FromFile(@"../../Resources/b.png"),
            System.Drawing.Image.FromFile(@"../../Resources/c.png")
        };

这里路径为什么是两层上级目录，因为Resources目录相对应bin/debug的目录如此

然后在窗体加载完的事件中对TreeList设置完数据源之后，设置每个节点的图标。

System.Windows.Forms.ImageList imgList = new System.Windows.Forms.ImageList();
imgList.Images.AddRange(imgs);
treeList1.SelectImageList = imgList;
treeList1.Nodes.FirstOrDefault().ImageIndex = 0;
treeList1.Nodes.FirstOrDefault().FirstNode.ImageIndex = 1;
treeList1.Nodes.FirstOrDefault().FirstNode.FirstNode.ImageIndex = 2;

这里是通过treeList1.Nodes.FirstOrDefault()找到第一个节点或者默认节点，即根节点。

然后通过FirstNode找到第一个子节点。

然后treeList1.SelectImageList = imgList设置其图标源是一个图标数组。

然后指定每个节点的ImageIndex 就是在图标数组中的索引。

完整示例代码：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace TreeListTest
{
    public partial class Form1 : Form
    {
       
        public static System.Drawing.Image[] imgs = new System.Drawing.Image[] { 
            System.Drawing.Image.FromFile(@"../../Resources/a.png"),
            System.Drawing.Image.FromFile(@"../../Resources/b.png"),
            System.Drawing.Image.FromFile(@"../../Resources/c.png")
        };

        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {

           
            #region 设置列头、节点指示器面板、表格线样式

            treeList1.OptionsView.ShowColumns = false;             //隐藏列标头
            treeList1.OptionsView.ShowIndicator = false;           //隐藏节点指示器面板
            treeList1.OptionsView.ShowHorzLines = false;           //隐藏水平表格线
            treeList1.OptionsView.ShowVertLines = false;           //隐藏垂直表格线
            treeList1.OptionsView.ShowIndentAsRowStyle = false;

            #endregion

            #region 初始禁用单元格选中，禁用整行选中

            treeList1.OptionsView.ShowFocusedFrame = true;                               //设置显示焦点框
            treeList1.OptionsSelection.EnableAppearanceFocusedCell = false;              //禁用单元格选中
            treeList1.OptionsSelection.EnableAppearanceFocusedRow = false;               //禁用正行选中

            #endregion

            #region 设置TreeList的展开折叠按钮样式和树线样式

            treeList1.OptionsView.ShowButtons = true;                  //显示展开折叠按钮
            treeList1.LookAndFeel.UseDefaultLookAndFeel = false;       //禁用默认外观与感觉
            treeList1.LookAndFeel.UseWindowsXPTheme = true;            //使用WindowsXP主题
            treeList1.TreeLineStyle = DevExpress.XtraTreeList.LineStyle.Percent50;     //设置树线的样式

            #endregion

            #region 添加单列

            DevExpress.XtraTreeList.Columns.TreeListColumn colNode = new DevExpress.XtraTreeList.Columns.TreeListColumn();
            colNode.Name = String.Format("col{0}", "NodeText");
            colNode.Caption = "NodeText";
            colNode.FieldName = "NodeText";
            colNode.VisibleIndex = 0;
            colNode.Visible = true;

            colNode.OptionsColumn.AllowEdit = false;                        //是否允许编辑
            colNode.OptionsColumn.AllowMove = false;                        //是否允许移动
            colNode.OptionsColumn.AllowMoveToCustomizationForm = false;     //是否允许移动至自定义窗体
            colNode.OptionsColumn.AllowSort = false;                        //是否允许排序
            colNode.OptionsColumn.FixedWidth = false;                       //是否固定列宽
            colNode.OptionsColumn.ReadOnly = true;                          //是否只读
            colNode.OptionsColumn.ShowInCustomizationForm = true;           //移除列后是否允许在自定义窗体中显示

            treeList1.Columns.Clear();
            treeList1.Columns.AddRange(new DevExpress.XtraTreeList.Columns.TreeListColumn[] { colNode });

            #endregion

            treeList1.KeyFieldName = "Id";
            treeList1.ParentFieldName = "ParentId";

            DataTreeNode node1 = new DataTreeNode();
            node1.Id = "1";
            node1.ParentId = null;
            node1.NodeText = "1公众号";

            DataTreeNode node11 = new DataTreeNode();
            node11.Id = "2";
            node11.ParentId = "1";
            node11.NodeText = "1-1霸道的程序猿";

            DataTreeNode node111 = new DataTreeNode();
            node111.Id = "3";
            node111.ParentId = "2";
            node111.NodeText = "1-1-1大量编程资源";


            List<DataTreeNode> data = new List<DataTreeNode>();

            data.Add(node1);
            data.Add(node11);
            data.Add(node111);
            
            treeList1.DataSource = data;
            treeList1.RefreshDataSource();

            System.Windows.Forms.ImageList imgList = new System.Windows.Forms.ImageList();
            imgList.Images.AddRange(imgs);

            treeList1.SelectImageList = imgList;

          
            
            treeList1.Nodes.FirstOrDefault().ImageIndex = 0;
            treeList1.Nodes.FirstOrDefault().FirstNode.ImageIndex = 1;
            treeList1.Nodes.FirstOrDefault().FirstNode.FirstNode.ImageIndex = 2;
        }
    }
}