Description:
The article demonstrates how to populate TreeView Control using SqlDataSource at
runtime in C#.NET. We can achieve intended result by simply executing SqlCommand
Object either by ExecuteReader or ExecuteNonQuery method.
The TreeView control has a Nodes collection with root TreeNode objects. Each
TreeNode in turn has its own Nodes collection that holds more than one child
TreeNode.
<TreeNode object>.Nodes.Add (TreeNode node) method adds a new tree node with the
specified text to the end of the current tree node collection
Procedure:
Step 1: Declaration of Connection, Command, and DataReader object
SqlConnection
Conn =
new
SqlConnection("Data
Source=.\\SQLExpress;
Initial Catalog=NorthWind;
Integrated Security=True");
SqlDataReader
rdr;
SqlCommand
cmd;
Listing 1
Step 2: Now, whatever the code required to written for populating the
SqlDataSource to the TreeView Control you can place it either into the click,
load etc. event handlers.
Step 3: We need to create two TreeNode Objects as follows
TreeNode
parent = treeView1.Nodes.Add("Suppliers");
TreeNode
child;
Listing 2
Step 4: Now pass the SqlQuery as an argument of SqlCommand Object and
stored the values into SqlDataReader Object.
cmd =
new SqlCommand("SqlQuery",
Conn);
Conn.Open();
rdr = cmd.ExecuteReader();
Listing 3
Step 5: Now retrieve the values from SqlDataReader and adds it to the
Child Nodes of Nodes Collection of TreeView Control.
while
(rdr.Read())
{
child = parent.Nodes.Add("Supplier ID: "
+ rdr.GetValue(0).ToString());
child.Nodes.Add("Name: " +
rdr.GetValue(1).ToString());
}
Listing 4
Intended Result:
![Treeview.gif]()
Figure 1
Summary:
In this article, we discussed how we can populate a DataTable from the
SqlDataSource into TreeView Control in C#.
Title Scrolling:
http://www.vbdotnetheaven.com/UploadFile/satyapriyanayak/8684/