小问题

private void button1_Click(object sender, EventArgs e)
  {
  //textBox1.Text = listView1.Items.ToString();
   
  string path = textBox1.Text;
  DirectoryInfo dirinfo = new DirectoryInfo(path);
  DirectoryInfo[] arrdirinfo;
  arrdirinfo = dirinfo.GetDirectories();
  listView1.Items.Clear();
  foreach (DirectoryInfo di in arrdirinfo)
  {
  ListViewItem liv = new ListViewItem(di.Name);
  if (Path.GetExtension(di.Name).ToString().ToUpper()=="RAR")
  {
  liv.ImageIndex = 2;
  }
  else
  {
  liv.ImageIndex = 3;
  }
  liv.SubItems.Add(di.LastWriteTime.ToString());
   
  listView1.Items.Add(liv);
  }
  }
问题1：为什么我注释的那行，textBox输出的是一段英文（好像是System.....什么什么的），而不是我选中的ITEMS的名字呢！
问题2：在if判定文件类型的时候怎么在测试的时候不行呢，完全没改变图标。。
求解答，谢谢！

listView1.Items.ToString是输出的Items类型
listView1.Items[0].Text才是内容

Path.GetExtension返回值中包括 '.'，好好看帮助

public ListViewItemCollection Items { get; }

Items返回类型可不是string 哦 
http://msdn.microsoft.com/zh-cn/library/system.windows.forms.listview.items(v=vs.80).aspx

if (Path.GetExtension(di.Name).TrimStart('.').ToString().ToUpper()=="RAR")

如果我想得到选中的SelectedItems的名字应该怎么写呢，我写了textBox1.Text = listView1.SelectedItems[0].ToString();
输出是listview1：{e:\},括号里面的才是我想要的值，怎么多了点东西呢！
还有第二个问题，用了上面2位的方法还是不行，不知道什么问题，我给全部代码你看看
public partial class Form1 : Form
  {
  public Form1()
  {
  InitializeComponent();
  }

  private void Form1_Load(object sender, EventArgs e)
  {
  textBox1.Text = "我的电脑";
  string[] arrDrives = Directory.GetLogicalDrives();
  foreach (string str in arrDrives)
  {
  ListViewItem liv = new ListViewItem(str, 0);
  listView1.Items.Add(liv);
   
  }
  }

  private void button1_Click(object sender, EventArgs e)
  {
   
  textBox1.Text = listView1.SelectedItems[0].ToString();
  string path = textBox1.Text;
  DirectoryInfo dirinfo = new DirectoryInfo(path);
  DirectoryInfo[] arrdirinfo;
  arrdirinfo = dirinfo.GetDirectories();
  listView1.Items.Clear();
  foreach (DirectoryInfo di in arrdirinfo)
  {
  ListViewItem liv = new ListViewItem(di.Name);
  if (Path.GetExtension(di.Name).TrimStart('.').ToString().ToUpper() == "RAR")
  {
  liv.ImageIndex = 2;
  }
  else
  {
  liv.ImageIndex = 3;
  }
  liv.SubItems.Add(di.LastWriteTime.ToString());

  listView1.Items.Add(liv);
  }
  }

  private void 大图标ToolStripMenuItem_Click(object sender, EventArgs e)
  {
  listView1.View = View.LargeIcon;
  }

  private void 小图标ToolStripMenuItem_Click(object sender, EventArgs e)
  {
  listView1.View = View.SmallIcon;
  }

  private void 详细ToolStripMenuItem_Click(object sender, EventArgs e)
  {
  listView1.View = View.Details;
  }

  private void 列表ToolStripMenuItem_Click(object sender, EventArgs e)
  {
  listView1.View = View.List;
  }

  }
求帮忙！谢谢