Mega Code Archive
Displaying database data with a TreeView control
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<%@ Page Language="C#" %>
<%@ Import Namespace="System.Web.Configuration" %>
<%@ Import Namespace="System.Data" %>
<%@ Import Namespace="System.Data.SqlClient" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN"
"http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd"><script runat="server">
void Page_Load()
{
if (!Page.IsPostBack)
PopulateTreeView();
}
private void PopulateTreeView()
{
DataTable treeViewData = GetTreeViewData();
AddTopTreeViewNodes(treeViewData);
}
private DataTable GetTreeViewData()
{
string selectCommand = "SELECT MessageId,ParentId,Subject FROM Discuss";
string conString = WebConfigurationManager.ConnectionStrings["Discuss"]. ConnectionString;
SqlDataAdapter dad = new SqlDataAdapter(selectCommand, conString);
DataTable dtblDiscuss = new DataTable();
dad.Fill(dtblDiscuss);
return dtblDiscuss;
}
private void AddTopTreeViewNodes(DataTable treeViewData)
{
DataView view = new DataView(treeViewData);
view.RowFilter = "ParentID IS NULL";
foreach (DataRowView row in view) {
TreeNode newNode = new TreeNode(row["Subject"].ToString(), row["MessageId"].ToString());
TreeView1.Nodes.Add(newNode);
AddChildTreeViewNodes(treeViewData, newNode);
}
}
private void AddChildTreeViewNodes(DataTable treeViewData, TreeNode parentTreeViewNode)
{
DataView view = new DataView(treeViewData);
view.RowFilter = "ParentID=" + parentTreeViewNode.Value;
foreach (DataRowView row in view)
{
TreeNode newNode = new TreeNode(row["Subject"].ToString(), row["MessageId"].ToString());
parentTreeViewNode.ChildNodes.Add(newNode);
AddChildTreeViewNodes(treeViewData, newNode);
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
<style type="text/css">
</style>
<title>TreeView Database</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:TreeView
id="TreeView1"
Runat="server" />
</div>
</form>
</body>
</html>
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