Question

我有下面的代码我想把一个全局方法设置为静态，以便我可以在我的asp.net Web应用程序上构建几个树视图。现在我使用下面的代码构建自己的树视图。我正在考虑制作一个全局静态方法来生成这样的节点结构，然后将它们分配给我的页面中的树视图......或类似的东西。我想关注实际解决方案的细节，只要我可以使用单个方法调用“buildTree（）”，它将能够用于将树视图控件绑定到。

恶棍？

DataTable dtProjects = new DataTable();
            DataTable dtRelease = new DataTable();

            using (SqlConnection con = Global.GetConnection())
            {
                StringBuilder str = new StringBuilder();
                str.Append("SELECT r.ReleaseId, ");
                str.Append("       r.Name, ");
                str.Append("       rs.EndDate ");
                str.Append("  FROM Release r ");
                str.Append("  LEFT OUTER JOIN ReleaseSchedule rs ");
                str.Append("    ON r.ReleaseId = rs.ReleaseId ");
                str.Append("   AND rs.MilestoneCID = 77");
                str.Append(" WHERE r.CompletionStatusCID NOT IN (34, 35) ");
                str.Append(" ORDER BY r.ReportingPriority, r.Name ");
                SqlDataAdapter da = new SqlDataAdapter(str.ToString(), con);
                da.Fill(dtRelease);

                str = new StringBuilder();
                str.Append("SELECT p.ProjectId, ");
                str.Append("       p.ProjectName, ");
                str.Append("       p.ParentProjectId, ");
                str.Append("       p.ReleaseId ");
                str.Append("  FROM Project p ");
                str.Append(" WHERE p.CompletionStatusCID NOT IN (34, 35) ");
                str.Append("   AND p.ProjectTypeCID <> 92 ");
                str.Append(" ORDER BY p.ProjectName ");

                da = new SqlDataAdapter(str.ToString(), con);
                da.Fill(dtProjects);
            }

            tvProject.Nodes.Clear();
            TreeNode rootNode = new TreeNode("All Projects");
            rootNode.Expanded = true;

            foreach (DataRow drRelease in dtRelease.Rows)
            {
                TreeNode releaseNode = new TreeNode((string)drRelease["Name"]);
                DataRow[] releaseProjects = dtProjects.Select("(ReleaseId = " + drRelease["ReleaseId"] + ") AND (ParentProjectId IS NULL)");

                foreach (DataRow drProject in releaseProjects)
                {
                    TreeNode projectNode = new TreeNode((string)drProject["ProjectName"], drProject["ProjectId"].ToString());
                    projectNode.ToolTip = "This is a project node and is selectable";
                    loadTVNode((int)drProject["ProjectId"], projectNode, dtProjects);
                    if (drRelease["EndDate"] != System.DBNull.Value)
                    {
                        string s = ((DateTime)drRelease["EndDate"]).ToString(Global.CONST_DateFormat);
                        releaseNode.ToolTip = "Release scheduled for deployment on " + s;
                    }
                    else
                        releaseNode.ToolTip = "Release deployment has not been scheduled";

                    releaseNode.ToolTip += ". This node is not selectable";
                    releaseNode.ChildNodes.Add(projectNode);
                }
                rootNode.ChildNodes.Add(releaseNode);
            }

            tvProject.Nodes.Add(rootNode);

Answer 1

我没有马上得到这个问题，但我想你正在寻找这样的事情：

使用一个公共方法创建一个名为TreeViewBuilder的类，以从现有方法返回填充的TreeView：

public class TreeViewBuilder
{
    public static TreeView BuildTreeView( TreeView tree )
    {
        DataTable projects = GetProjects();
        DataTable releases = GetRealeases();

        return InternalTreeViewBuilder(tree, projects, releases);
    }
}

我的猜测是，您可以填写此解决方案中的空白，例如传递您需要的参数等等。您还可以为您在问题中放置的代码调用树方法构建代码。你现在创建例程：

//TreeView something;
TreeViewBuilder.BuildTreeView(something);

更酷的是，如果你使用超过3.5的.NET框架，你可以将该方法作为扩展：

public static class TreeViewBuilder
{
    public static TreeView BuildTreeView( this TreeView tree )
    {
        DataTable projects = GetProjects();
        DataTable releases = GetRealeases();

        return InternalTreeViewBuilder(tree, projects, releases);
    }
}

然后，调用你的方法会简单得多：

//TreeView something;
something.BuildTreeView();

它已经完成了！ MSDN有一些很好的扩展方法代码。

希望我能帮忙！

如何抽象树视图节点创建/人口？

1 个答案: