我正在尝试使用Shell32在c#中获取扩展文件属性。
我的代码如下。
var file = FileUpload1.PostedFile;
List<string> arrHeaders = new List<string>();
Shell shell = new ShellClass();
//Exception is thrown at next line
Folder rFolder = shell.NameSpace(Path.GetDirectoryName(file.FileName));
FolderItem rFiles = rFolder.ParseName(Path.GetFileName(file.FileName));
for (int i = 0; i < short.MaxValue; i++)
{
string value = rFolder.GetDetailsOf(rFiles, i).Trim();
arrHeaders.Add(value);
}
我得到如下例外情况。
消息 - 无法转换类型为&#39; Shell32.ShellClass&#39;的COM对象接口类型&#39; Shell32.IShellDispatch6&#39;。此操作失败,因为QueryInterface调用COM组件上的接口与IID&#39; {286E6F1B-7113-4355-9562-96B7E9D64C54}&#39;由于以下错误而失败:不支持此类接口(HRESULT异常:0x80004002(E_NOINTERFACE))。
Stack Trace - 在System.StubHelpers.StubHelpers.GetCOMIPFromRCW(Object objSrc,IntPtr pCPCMD,IntPtr&amp; ppTarget,Boolean&amp; pfNeedsRelease) 在Shell32.ShellClass.NameSpace(对象vDir) at PBSWebApplication.Test.Button1_OnClick(Object sender,EventArgs e)位于c:\ Projects \ PBSWebApplication \ PBSWebApplication \ PBSWebApplication \ Test.aspx.cs:第33行 在System.Web.UI.WebControls.Button.OnClick(EventArgs e) 在System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) 在System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) 在System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl,String eventArgument) 在System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) 在System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint,Boolean includeStagesAfterAsyncPoint)
如何解决这个问题?
感谢。
答案 0 :(得分:15)
正如您所知,这是因为Shell32需要一个STA线程。如果您不能像在解决方案中那样简单地将应用程序配置为使用STA线程运行,那么您可以创建一个单独的STA线程,使用它来运行Shell32代码,然后继续执行。例如this是我在编写SSIS脚本任务时最终得到的,据我所知,它始终在MTA线程上运行。在我的情况下,我调用了一个不同的Shell32方法(CopyHere),但是相同的逻辑将适用于你想要调用的任何方法:
/// <summary>
/// Ugh! SSIS runs script tasks on MTA threads but Shell32 only wants to
/// run on STA thread. So start a new STA thread to call UnZip, block
/// till it's done, then return.
/// We use Shell32 since .net 2 doesn't have ZipFile and we prefer not to
/// ship other dlls as they normally need to be deployed to the GAC. So this
/// is easiest, although not very pretty.
/// </summary>
/// <param name="zipFile">File to unzip</param>
/// <param name="folderPath">Folder to put the unzipped files</param>
public static void UnZipFromMTAThread(string zipFile, string folderPath)
{
object[] args = new object[] { zipFile, folderPath };
if (Thread.CurrentThread.GetApartmentState() == ApartmentState.STA)
{
UnZip(args);
}
else
{
Thread staThread = new Thread(new ParameterizedThreadStart(UnZip));
staThread.SetApartmentState(ApartmentState.STA);
staThread.Start(args);
staThread.Join();
}
}
/// <summary>
/// From http://www.fluxbytes.com/csharp/unzipping-files-using-shell32-in-c/ but with
/// args packed in object array so can be called from new STA Thread in UnZipFromMTAThread().
/// </summary>
/// <param name="param">object array containing: [string zipFile, string destinationFolderPath]</param>
private static void UnZip(object param)
{
object[] args = (object[]) param;
string zipFile = (string)args[0];
string folderPath = (string)args[1];
if (!File.Exists(zipFile))
throw new FileNotFoundException();
if (!Directory.Exists(folderPath))
Directory.CreateDirectory(folderPath);
Shell32.Shell objShell = new Shell32.Shell();
Shell32.Folder destinationFolder = objShell.NameSpace(folderPath);
Shell32.Folder sourceFile = objShell.NameSpace(zipFile);
foreach (var file in sourceFile.Items())
{
// Flags are: No progress displayed, Respond with 'Yes to All' for any dialog, no UI on error
// I added 1024 although not sure it's relevant with Zip files.
// See https://msdn.microsoft.com/en-us/library/windows/desktop/bb787866%28v=vs.85%29.aspx?f=255&MSPPError=-2147217396
destinationFolder.CopyHere(file, 4 | 16 | 1024);
}
}
答案 1 :(得分:3)
事实证明,将STAThread
属性添加到我的班级是一个简单的解决方案,但问题却神奇地消失了。
这是我更新后的完整代码。
注意:这是一个简单的控制台应用程序。
class Program
{
[STAThread]
static void Main(string[] args)
{
Console.Title = "Extended file properties.";
List<string> arrHeaders = new List<string>();
Shell32.Shell shell = new Shell32.Shell();
Shell32.Folder objFolder;
objFolder = shell.NameSpace(@"C:\Users\Admin\Pictures\PBS Docs");
for (int i = 0; i < short.MaxValue; i++)
{
string header = objFolder.GetDetailsOf(null, i);
if (String.IsNullOrEmpty(header))
break;
arrHeaders.Add(header);
}
foreach (Shell32.FolderItem2 item in objFolder.Items())
{
for (int i = 0; i < arrHeaders.Count; i++)
{
Console.WriteLine("{0}\t{1}: {2}", i, arrHeaders[i], objFolder.GetDetailsOf(item, i));
}
}
}
}
答案 2 :(得分:3)
我有类似问题,jeronevw在这个论坛上的答案为我修好了: https://social.msdn.microsoft.com/Forums/vstudio/en-US/b25e2b8f-141a-4a1c-a73c-1cb92f953b2b/instantiate-shell32shell-object-in-windows-8?forum=clr
public Shell32.Folder GetShell32NameSpaceFolder(Object folder)
{
Type shellAppType = Type.GetTypeFromProgID("Shell.Application");
Object shell = Activator.CreateInstance(shellAppType);
return (Shell32.Folder)shellAppType.InvokeMember("NameSpace",
System.Reflection.BindingFlags.InvokeMethod, null, shell, new object[] { folder });
}
jeronevw的所有学分