private void listViewFiles_ItemDrag(object sender, ItemDragEventArgs e)
{
  if (this.listViewFiles.SelectedItems.Count == 1)
  {
    DataObject dt = new DataObject(DataFormats.FileDrop, (string)this.listViewFiles.SelectedItems[0].Tag);
    this.listViewFiles.DoDragDrop(dt, DragDropEffects.Copy);
  }
}

DataObject dataObj = null;
private void listViewFiles_ItemDrag(object sender, ItemDragEventArgs e)
{
 dataObj = new DataObject();
 String[] fileNames;
 //Create an array of strings to hold the filename(s)
 fileNames = new String[this.listViewFiles.SelectedItems.Count];
 //Create temporary files that the user can drag.
 for (int i = 0; i < this.listViewFiles.SelectedItems.Count; i++)
  fileNames[i] = (string)this.listViewFiles.SelectedItems[i].Tag;
 
 //Add the list of files to the data object
 dataObj.SetData(DataFormats.FileDrop, fileNames);
 //Set the preferred drop effect
 dataObj.SetData(ShellClipboardFormats.CFSTR_PREFERREDDROPEFFECT, DragDropEffects.Copy);
 //Indicate that we are in a drag loop
 dataObj.SetData(ShellClipboardFormats.CFSTR_INDRAGLOOP, 1);
 this.listViewFiles.DoDragDrop(dataObj, DragDropEffects.Copy);
 //Free the data object
 dataObj = null;
}
 
private void listViewFiles_QueryContinueDrag(object sender, QueryContinueDragEventArgs e)
{
 //ESC pressed
 if (e.EscapePressed)
 {
  e.Action = DragAction.Cancel;
  return;
 }
 //Drop!
 if (e.KeyState == 0)
 {
  dataObj.SetData(ShellClipboardFormats.CFSTR_INDRAGLOOP, 0);
  e.Action = DragAction.Drop;
  return;
 }
 e.Action = DragAction.Continue;
}

public class ShellClipboardFormats
{
public const string CFSTR_SHELLIDLIST = "Shell IDList Array";
public const string CFSTR_SHELLIDLISTOFFSET = "Shell Object Offsets";
public const string CFSTR_NETRESOURCES = "Net Resource";
public const string CFSTR_FILEDESCRIPTORA = "FileGroupDescriptor";
public const string CFSTR_FILEDESCRIPTORW = "FileGroupDescriptorW";
public const string CFSTR_FILECONTENTS = "FileContents";
public const string CFSTR_FILENAMEA = "FileName";
public const string CFSTR_FILENAMEW = "FileNameW";
public const string CFSTR_PRINTERGROUP = "PrinterFreindlyName";
public const string CFSTR_FILENAMEMAPA = "FileNameMap";
public const string CFSTR_FILENAMEMAPW = "FileNameMapW";
public const string CFSTR_SHELLURL = "UniformResourceLocator";
public const string CFSTR_INETURLA = CFSTR_SHELLURL;
public const string CFSTR_INETURLW = "UniformResourceLocatorW";
public const string CFSTR_PREFERREDDROPEFFECT = "Preferred DropEffect";
public const string CFSTR_PERFORMEDDROPEFFECT = "Performed DropEffect";
public const string CFSTR_PASTESUCCEEDED = "Paste Succeeded";
public const string CFSTR_INDRAGLOOP = "InShellDragLoop";
public const string CFSTR_DRAGCONTEXT = "DragContext";
public const string CFSTR_MOUNTEDVOLUME = "MountedVolume";
public const string CFSTR_PERSISTEDDATAOBJECT = "PersistedDataObject";
public const string CFSTR_TARGETCLSID = "TargetCLSID";
public const string CFSTR_LOGICALPERFORMEDDROPEFFECT = "Logical Performed DropEffect";
public const string CFSTR_AUTOPLAY_SHELLIDLISTS = "Autoplay Enumerated IDList Array";
}