获取可用动词列表（文件关联）以在 c# 中与 ProcessStartInfo 一起使用

Question

我正在尝试使用 ProcessStartInfo class 打开和打印文件。（文件可以是任何东西，但我们假设它是一个 PDF 文件）

  ProcessStartInfo pi = new ProcessStartInfo(file);
  pi.Arguments = Path.GetFileName(file);
  pi.WorkingDirectory = Path.GetDirectoryName(file);
  pi.Verb = "OPEN";  
  Process.Start(pi);

这适用于 pi.Verb = "OPEN";。一些应用程序也使用动词 "PRINT" 注册自己，但只有一些应用程序这样做。在我的例子中（Windows PDF 查看器）我在尝试使用 pi.Verb = "PRINT";

执行时遇到异常

有没有办法在运行时查看 C# 中特定类型的所有动词？

非常感谢

Answer 1

来自 MSDN：https://msdn.microsoft.com/en-us/library/65kczb9y(v=vs.110).aspx?cs-save-lang=1&cs-lang=csharp#code-snippet-2

 startInfo = new ProcessStartInfo(fileName);

    if (File.Exists(fileName))
    {
        i = 0;
        foreach (String verb in startInfo.Verbs)
        {
            // Display the possible verbs.
            Console.WriteLine("  {0}. {1}", i.ToString(), verb);
            i++;
        }
    }

Answer 2

ProcessStartInfo.Verbs 属性有些问题，因为它没有考虑更新版本的 Windows（Windows 8 及更高版本 afaik）检索已注册应用程序的方式. 属性只检查在 HKCR\.ext 下定义的 ProgId 注册的动词（在 reference source 中可以看到）并且不考虑其他地方，例如在注册表键 HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\FileExts\.ext 或其他一些地方，例如通过策略定义。

获取注册动词

最好的方法是不要依赖直接检查注册表（如 ProcessStartInfo class 所做的那样），而是使用适当的 Windows API 函数AssocQueryString 检索关联的 ProgId：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Diagnostics;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;
using Microsoft.Win32;

class Program
{
    private static void Main(string[] args)
    {
        string fileName = @"E:\Pictures\Sample.jpg";
        string progId = AssocQueryString(AssocStr.ASSOCSTR_PROGID, fileName);

        var verbs = GetVerbsByProgId(progId);

        if (!verbs.Contains("printto"))
        {
            throw new Exception("PrintTo is not supported!");
        }

    }

    private static string[] GetVerbsByProgId(string progId)
    {
        var verbs = new List<string>();

        if (!string.IsNullOrEmpty(progId))
        {
            using (var key = Registry.ClassesRoot.OpenSubKey(progId + "\shell"))
            {
                if (key != null)
                {
                    var names = key.GetSubKeyNames();
                    verbs.AddRange(
                        names.Where(
                            name => 
                                string.Compare(
                                    name, 
                                    "new", 
                                    StringComparison.OrdinalIgnoreCase) 
                                != 0));
                }
            }
        }

        return verbs.ToArray();
    }

    private static string AssocQueryString(AssocStr association, string extension)
    {
        uint length = 0;
        uint ret = AssocQueryString(
            AssocF.ASSOCF_NONE, association, extension, "printto", null, ref length);
        if (ret != 1) //expected S_FALSE
        {
            throw new Win32Exception();
        }

        var sb = new StringBuilder((int)length);
        ret = AssocQueryString(
            AssocF.ASSOCF_NONE, association, extension, null, sb, ref length);
        if (ret != 0) //expected S_OK
        {
            throw new Win32Exception();
        }

        return sb.ToString();
    }

    [DllImport("Shlwapi.dll", CharSet = CharSet.Unicode, SetLastError = true)]
    private static extern uint AssocQueryString(
        AssocF flags,
        AssocStr str,
        string pszAssoc,
        string pszExtra,
        [Out] StringBuilder pszOut,
        ref uint pcchOut);

    [Flags]
    private enum AssocF : uint
    {
        ASSOCF_NONE = 0x00000000,
        ASSOCF_INIT_NOREMAPCLSID = 0x00000001,
        ASSOCF_INIT_BYEXENAME = 0x00000002,
        ASSOCF_OPEN_BYEXENAME = 0x00000002,
        ASSOCF_INIT_DEFAULTTOSTAR = 0x00000004,
        ASSOCF_INIT_DEFAULTTOFOLDER = 0x00000008,
        ASSOCF_NOUSERSETTINGS = 0x00000010,
        ASSOCF_NOTRUNCATE = 0x00000020,
        ASSOCF_VERIFY = 0x00000040,
        ASSOCF_REMAPRUNDLL = 0x00000080,
        ASSOCF_NOFIXUPS = 0x00000100,
        ASSOCF_IGNOREBASECLASS = 0x00000200,
        ASSOCF_INIT_IGNOREUNKNOWN = 0x00000400,
        ASSOCF_INIT_FIXED_PROGID = 0x00000800,
        ASSOCF_IS_PROTOCOL = 0x00001000,
        ASSOCF_INIT_FOR_FILE = 0x00002000
    }

    private enum AssocStr
    {
        ASSOCSTR_COMMAND = 1,
        ASSOCSTR_EXECUTABLE,
        ASSOCSTR_FRIENDLYDOCNAME,
        ASSOCSTR_FRIENDLYAPPNAME,
        ASSOCSTR_NOOPEN,
        ASSOCSTR_SHELLNEWVALUE,
        ASSOCSTR_DDECOMMAND,
        ASSOCSTR_DDEIFEXEC,
        ASSOCSTR_DDEAPPLICATION,
        ASSOCSTR_DDETOPIC,
        ASSOCSTR_INFOTIP,
        ASSOCSTR_QUICKTIP,
        ASSOCSTR_TILEINFO,
        ASSOCSTR_CONTENTTYPE,
        ASSOCSTR_DEFAULTICON,
        ASSOCSTR_SHELLEXTENSION,
        ASSOCSTR_DROPTARGET,
        ASSOCSTR_DELEGATEEXECUTE,
        ASSOCSTR_SUPPORTED_URI_PROTOCOLS,
        ASSOCSTR_PROGID,
        ASSOCSTR_APPID,
        ASSOCSTR_APPPUBLISHER,
        ASSOCSTR_APPICONREFERENCE,
        ASSOCSTR_MAX
    }
}

获取可用动词列表（文件关联）以在 c# 中与 ProcessStartInfo 一起使用

Get List of available Verbs (file association) to use with ProcessStartInfo in c#

c#

processstartinfo

file-association

获取注册动词