动态创建树视图 [英] Dynamically create treeview

问题描述

我想显示一个分层结构，我希望使用asp.net在vb.net中重新启动treeview这个结构

I want to display a hierarchical structure, i want retrrive the treeview this structure in vb.net using asp.net

__ID__  | __NAME__  | __PARENT__|
 1      | Patrick   | primary
 2      | Mark      | primary
 3      | Scott     | Mark
 4      | Jason     | Patrick
 5      | Julian    | Primary
 6      | John      | Scott
 7      | Steve     | Scott
 8      | George    | Patrick
 9      | Robert    | George
 10     | Rodney    | George

删除了SHOUTING，添加了代码块 - OriginalGriff [/ edit]

[edit]SHOUTING removed, Code block added - OriginalGriff[/edit]

推荐答案

在VB中查看

See in VB

Private Sub BindTreeViewControl()
	Try
		Dim dt As New DataTable() 
		'Assign your database value to dt table  where dt is null now
		Dim dtParent As DataTable = (From f In dt.AsEnumerable() Where f.Field(Of String)("PARENT").ToLower() = "primary"f).ToList().CopyToDataTable()
		For i As Integer = 0 To dtParent.Rows.Count - 1
			Dim root As New TreeNode(dtParent.Rows(i)("NAME").ToString(), dtParent.Rows(i)("ID").ToString())
			root.SelectAction = TreeNodeSelectAction.Expand
			CreateNode(root, dt)
			'Sending table
			TreeView1.Nodes.Add(root)
		Next
	Catch Ex As Exception
		Throw Ex
	End Try
End Sub


Public Sub CreateNode(node As TreeNode, Dt As DataTable)
	Dim dtChild As New DataTable()
	Dim varChiled = (From f In Dt.AsEnumerable() Where f.Field(Of String)("PARENT").ToLower() = node.Text.ToLower()f).ToList()
	If varChiled.Count > 0 Then
		dtChild = varChiled.CopyToDataTable()
	End If
	If dtChild.Rows.Count = 0 Then
		Return
	End If
	For i As Integer = 0 To dtChild.Rows.Count - 1
		Dim Childnode As New TreeNode(dtChild.Rows(i)("NAME").ToString(), dtChild.Rows(i)("ID").ToString())
		Childnode.SelectAction = TreeNodeSelectAction.Expand
		node.ChildNodes.Add(Childnode)
		CreateNode(Childnode, Dt)
	Next
End Sub

看看这里：演练：显示分层TreeView控件中的数据 [ ^ ]

看！

为它做了代码

See !
did the code for it

private void BindTreeViewControl()
   {
       try
       {
           DataTable dt = new DataTable();
           dt.Columns.Add("ID", typeof(int));
           dt.Columns.Add("NAME", typeof(string));
           dt.Columns.Add("PARENT", typeof(string));
           dt.Rows.Add(1, "Patrick ", "primary");
           dt.Rows.Add(2, "Mark", "primary");
           dt.Rows.Add(3, "Scott", "Mark");
           dt.Rows.Add(4, "Jason", "Patrick");
           dt.Rows.Add(5, "Julian", "Primary");
           dt.Rows.Add(6, "John", "Scott");
           dt.Rows.Add(7, " Steve", "Scott");
           dt.Rows.Add(8, " George", "Patrick");
           dt.Rows.Add(9, "Robert", "George");
           dt.Rows.Add(10, "Rodney", "George");
           // DataRow[] Rows = dt.Select("ParentId IS NULL"); Get all parents nodes
           DataTable dtParent = (from f in dt.AsEnumerable()
                                 where f.Field<string>("PARENT").ToLower() == "primary"
                                 select f).ToList().CopyToDataTable();
           for (int i = 0; i < dtParent.Rows.Count; i++)
           {
               TreeNode root = new TreeNode(dtParent.Rows[i]["NAME"].ToString(), dtParent.Rows[i]["ID"].ToString());
               root.SelectAction = TreeNodeSelectAction.Expand;
               CreateNode(root, dt);//Sending table
               TreeView1.Nodes.Add(root);
           }
       }
       catch (Exception Ex) { throw Ex; }
   }
   public void CreateNode(TreeNode node, DataTable Dt)
   {
       DataTable dtChild = new DataTable();
       var varChiled = (from f in Dt.AsEnumerable()
                             where f.Field<string>("PARENT").ToLower() == node.Text.ToLower()
                             select f).ToList();
       if (varChiled.Count > 0) dtChild = varChiled.CopyToDataTable();
       if (dtChild.Rows.Count == 0) { return; }
       for (int i = 0; i < dtChild.Rows.Count; i++)
       {
           TreeNode Childnode = new TreeNode(dtChild.Rows[i]["NAME"].ToString(), dtChild.Rows[i]["ID"].ToString());
           Childnode.SelectAction = TreeNodeSelectAction.Expand;
           node.ChildNodes.Add(Childnode);
           CreateNode(Childnode, Dt);
       }
   }

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