创建一个组织机构类，包含Id，组织机构名称，父机构Id等属性，构建组织机构集合，通过TreeView控件显示组织机构，体现递归思想

好的，以下是一个示例代码：

首先，我们可以创建一个表示组织机构的类，例如：

public class Organization
{
    public int Id { get; set; }
    public string Name { get; set; }
    public int ParentId { get; set; }
    public List<Organization> SubOrganizations { get; set; }
}

这个类有一个 id 属性、名称属性、父机构 id 属性和一个子组织机构列表属性，表示该组织机构的编号、名称、父机构编号和该组织机构的子机构列表。

接下来，我们可以创建一个组织机构集合类来管理所有的组织机构：

public class OrganizationCollection
{
    public List<Organization> Organizations { get; set; }
}

这个类有一个组织机构列表属性，表示所有的组织机构。

然后，我们可以使用这些类来构建组织机构集合，并且使用递归方式实现在 TreeView 控件中显示组织机构：

private void PopulateTreeView(TreeView treeView, List<Organization> organizations, int parentId)
{
    var nodes = organizations.Where(x => x.ParentId == parentId).ToList();

    foreach (var node in nodes)
    {
        var treeNode = new TreeNode(node.Name)
        {
            Tag = node.Id
        };

        if (node.SubOrganizations.Any())
        {
            PopulateTreeView(treeNode, node.SubOrganizations);
        }

        treeView.Nodes.Add(treeNode);
    }
}

private void PopulateTreeView(TreeNode parentNode, List<Organization> subOrganizations)
{
    foreach (var subOrganization in subOrganizations)
    {
        var treeNode = new TreeNode(subOrganization.Name)
        {
            Tag = subOrganization.Id
        };

        if (subOrganization.SubOrganizations.Any())
        {
            PopulateTreeView(treeNode, subOrganization.SubOrganizations);
        }

        parentNode.Nodes.Add(treeNode);
    }
}

private void Form1_Load(object sender, EventArgs e)
{
    var organizationCollection = new OrganizationCollection();

    var organization1 = new Organization
    {
        Id = 1,
        Name = "Acme Inc.",
        ParentId = 0,
        SubOrganizations = new List<Organization>
        {
            new Organization
            {
                Id = 2,
                Name = "Sales",
                ParentId = 1,
                SubOrganizations = new List<Organization>
                {
                    new Organization
                    {
                        Id = 3,
                        Name = "North America",
                        ParentId = 2,
                        SubOrganizations = new List<Organization>()
                    },
                    new Organization
                    {
                        Id = 4,
                        Name = "Europe",
                        ParentId = 2,
                        SubOrganizations = new List<Organization>()
                    }
                }
            },
            new Organization
            {
                Id = 5,
                Name = "Marketing",
                ParentId = 1,
                SubOrganizations = new List<Organization>
                {
                    new Organization
                    {
                        Id = 6,
                        Name = "Online",
                        ParentId = 5,
                        SubOrganizations = new List<Organization>()
                    },
                    new Organization
                    {
                        Id = 7,
                        Name = "Offline",
                        ParentId = 5,
                        SubOrganizations = new List<Organization>()
                    }
                }
            }
        }
    };

    organizationCollection.Organizations = new List<Organization> { organization1 };

    PopulateTreeView(treeView1, organizationCollection.Organizations, 0);
}

在这个示例中，我们创建了一个名为 "Acme Inc." 的组织机构，该组织机构有两个子机构：销售和市场营销。销售机构下面有北美和欧洲两个子机构，市场营销机构下面有在线和离线两个子机构。使用递归的方式，我们能够在 TreeView 控件中显示所有的组织机构层次关系。