VirtualDirectory Constructor (String)

 

Initializes a new instance of the VirtualDirectory class.

Namespace:   System.Web.Hosting
Assembly:  System.Web (in System.Web.dll)

protected VirtualDirectory(
	string virtualPath
)

Parameters

virtualPath
Type: System.String

The virtual path to the resource represented by this instance.

The following code example is an implementation of the VirtualDirectory constructor that retrieves virtual file information from a DataSet object provided by a custom VirtualPathProvider object. It includes the GetData method used to populate the VirtualDirectory instance. For the full code required to run the example, see the Example section of the VirtualDirectory class overview.

public SampleVirtualDirectory(string virtualDir, SamplePathProvider provider)
  : base(virtualDir)
{
  spp = provider;
  GetData();
}

protected void GetData()
{
  DataSet ds = spp.GetVirtualData();

  // Clean up the path to match data in resource file.
  string path = VirtualPath.Replace(HostingEnvironment.ApplicationVirtualPath, "");
  path = path.TrimEnd('/');

  // Get the virtual directory from the resource table.
  DataTable dirs = ds.Tables["resource"];
  DataRow[] rows = dirs.Select(
    String.Format("(name = '{0}') AND (type='dir')", path));

  // If the select returned a row, the directory exists.
  if (rows.Length > 0)
  {
    exists = true;

    // Get children from the resource table.
    // This technique works for small numbers of virtual resources.
    //   Sites with moderate to large numbers of virtual
    //   resources should choose a method that consumes fewer
    //   computer resources.
    DataRow[] childRows = dirs.Select(
      String.Format("parentPath = '{0}'", path));

    foreach (DataRow childRow in childRows)
    {
      string childPath = (string)childRow["path"];

      if (childRow["type"].ToString() == "dir")
      {
        SampleVirtualDirectory svd = new SampleVirtualDirectory(childPath, spp);
        children.Add(svd);
        directories.Add(svd);
      }
      else
      {
        SampleVirtualFile svf = new SampleVirtualFile(childPath, spp);
        children.Add(svf);
        files.Add(svf);
      }
    }
  }
}

.NET Framework
Available since 2.0
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