Try the following code in your aspx or ascx file:
And in the codebehind to populate it:
private void PopulateTreeView()
{
DataSet ds = new DataSet(); //(populate the dataset with the table)
//Use LINQ to filter out items without a parent
DataTable parents = ds.Tables[0].AsEnumerable()
.Where(i => i.Field("parentid") == DBNull.Value)
.CopyToDataTable();
//Use LINQ to filter out items with parent
DataTable children = ds.Tables[0].AsEnumerable()
.Where(i => i.Field("parentid") != DBNull.Value)
.OrderBy(i => i.Field("parentid"))
.CopyToDataTable();
//Add the parents to the treeview
foreach(DataRow dr in parents)
{
TreeNode node = new TreeNode();
node.Text = dr["name"].ToString();
node.Value = dr["id"].ToString();
TreeView1.Nodes.Add(node);
}
//Add the children to the parents
foreach(DataRow dr in children)
{
TreeNode node = new TreeNode();
node.Text = dr["name"].ToString();
node.Value = dr["id"].ToString();
TreeNode parentNode = FindNodeByValue(dr["parentid"].ToString());
if(parentNode != null)
parentNode.ChildNodes.Add(node);
}
}
private TreeNode FindNodeByValue(string value)
{
foreach(TreeNode node in TreeView1.Nodes)
{
if(node.Value = value) return node;
TreeNode pnode = FindNodeRecursion(node, value);
if(pnode != null) return pnode;
}
return null;
}
private TreeNode FindNodeRecursion(TreeNode parentNode, string value)
{
foreach(TreeNode node in parentNode.ChildNodes)
{
if(node.Value = value) return node;
TreeNode pnode = FindNodeRecursion(node, value);
if(pnode != null) return pnode;
}
return null;
}
There might be a better way to do this and I haven't tested it, but it should work. Or you could always try out Telerik or another third party tool that makes data binding for these types of controls super easy.
加载中...