you can see the code that uses the static GeTDrives method of the DriveInfo class to get a list of all installed drives, then iterates through them. For each fixed, formatted, and available (ready) drive, the code creates a new node containing details of the drive. It then sets the ImageUrl to the custom image, specifies that clicking this node will cause a postback that executes the "populate on demand" event handler, and adds the node to the treeView.
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="TreeView.aspx.cs" Inherits="TreeView" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head runat="server"> <title>Untitled Page</title> </head> <body> <form id="form1" runat="server"> <div> <asp:TreeView ID="treeDir" runat="Server"> </asp:TreeView> <asp:Label ID="lblError" runat="Server"></asp:Label> </div> </form> </body> </html>
using System; using System.Data; using System.Configuration; using System.Collections; using System.Web; using System.Web.Security; using System.Web.UI; using System.Web.UI.WebControls; using System.Web.UI.WebControls.WebParts; using System.Web.UI.HtmlControls; using System.Text; using System.IO; public partial class TreeView : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { CreateTreeView(); } private void CreateTreeView() { treeDir.Nodes.Clear(); TreeNode node = new TreeNode("My Computer", "Root"); node.SelectAction = TreeNodeSelectAction.None; node.Expanded = true; treeDir.Nodes.Add(node); try { // get a list of installed drives DriveInfo[] allDrives = DriveInfo.GetDrives(); foreach (DriveInfo d in allDrives) { // only include fixed drives that are ready if (d.DriveType == DriveType.Fixed && d.IsReady) { // create text for the TreeView to display StringBuilder sb = new StringBuilder(); sb.Append(d.Name.Substring(0, 2)); sb.Append(" "); sb.Append(d.VolumeLabel); sb.Append(" ("); sb.Append(d.DriveFormat); sb.Append(") "); Double space = d.AvailableFreeSpace / 1024 / 1024; sb.Append(space.ToString("#,###,###,##0")); sb.Append(" MB available"); String theName = sb.ToString(); String theValue = d.Name; // add a node to the TreeView with "drive" image TreeNode child = new TreeNode(theName, theValue); child.ImageUrl = "images/icon_drive.gif"; // specify postback for populating child nodes child.SelectAction = TreeNodeSelectAction.Expand; child.PopulateOnDemand = true; node.ChildNodes.Add(child); } } } catch (Exception ex) { lblError.Text = "ERROR: " + ex.Message + "<p />"; } } }
