询问Windows 7 - 默认情况下,哪个程序打开此文件

Question

是否跳过注册表是询问哪些程序路径在Windows 7上打开此文件扩展名(.avi)的最佳方式？或者是否有更好的API使用？

在注册表中导航的正确方法是什么？我注意到当我安装DivX播放器时它从VLC播放器中偷走了.avi扩展名.我正好在文件的顶部并将默认程序设置为VLC,但我看不到它存储在HKCU中的哪个位置.

我的最终目标是让程序知道与文件扩展名相关联的应用程序.我想让它询问操作系统,而不是存储我自己的独立查找数据.

Answer 1

你不说你正在开发用什么语言,但是你应该能够调用做到这一点assocquerystring的shlwapi.dll.

该assocquerystringAPI函数将返回文件关联的数据,而不必手动潜入注册表和处理谎言中的恶魔.大多数语言都支持调用Windows API,所以你应该好好去.

更多信息可以在这里找到:

http://www.pinvoke.net/default.aspx/shlwapi.assocquerystring

和这里:

http://msdn.microsoft.com/en-us/library/bb773471%28VS.85%29.aspx

编辑:一些示例代码:

private void SomeProcessInYourApp()
{
    // Get association for doc/avi
    string docAsscData = AssociationsHelper.GetAssociation(".doc"); // returns : docAsscData = "C:\\Program Files\\Microsoft Office\\Office12\\WINWORD.EXE"
    string aviAsscData = AssociationsHelper.GetAssociation(".avi"); // returns : aviAsscData = "C:\\Program Files\\Windows Media Player\\wmplayer.exe"

    // Get association for an unassociated extension
    string someAsscData = AssociationsHelper.GetAssociation(".blahdeblahblahblah"); // returns : someAsscData = "C:\\Windows\\system32\\shell32.dll"
}

internal static class AssociationsHelper
{
    [DllImport("Shlwapi.dll", SetLastError = true, CharSet = CharSet.Auto)]
    static extern uint AssocQueryString(AssocF flags, AssocStr str, string pszAssoc, string pszExtra,
        [Out] StringBuilder pszOut, [In][Out] ref uint pcchOut);

    [Flags]
    enum AssocF
    {
        Init_NoRemapCLSID = 0x1,
        Init_ByExeName = 0x2,
        Open_ByExeName = 0x2,
        Init_DefaultToStar = 0x4,
        Init_DefaultToFolder = 0x8,
        NoUserSettings = 0x10,
        NoTruncate = 0x20,
        Verify = 0x40,
        RemapRunDll = 0x80,
        NoFixUps = 0x100,
        IgnoreBaseClass = 0x200
    }

    enum AssocStr
    {
        Command = 1,
        Executable,
        FriendlyDocName,
        FriendlyAppName,
        NoOpen,
        ShellNewValue,
        DDECommand,
        DDEIfExec,
        DDEApplication,
        DDETopic
    }

    public static string GetAssociation(string doctype)
    {
        uint pcchOut = 0;   // size of output buffer

        // First call is to get the required size of output buffer
        AssocQueryString(AssocF.Verify, AssocStr.Executable, doctype, null, null, ref pcchOut);

        // Allocate the output buffer
        StringBuilder pszOut = new StringBuilder((int)pcchOut);

        // Get the full pathname to the program in pszOut
        AssocQueryString(AssocF.Verify, AssocStr.Executable, doctype, null, pszOut, ref pcchOut);

        string doc = pszOut.ToString();
        return doc;
    }
}