Registry path to icon resource

Question

I have virtual files in my app. I would like to display the associated icon for these. In the registry I find the following target under various paths:

C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC#\VCSPackages\csproj.dll,1

However, this DLL does not contain the icon that Windows Explorer displays for a CS file.

Under which registry path can I find the entry to the file from which I can extract the CS icon?

Answer 1

If you want to extract the icon from an extension, you can do :

SHFILEINFO sfi = new SHFILEINFO();
IntPtr hImageList = SHGetFileInfo(".cs", 0, ref sfi, (uint)Marshal.SizeOf(sfi), SHGFI_ICON | SHGFI_USEFILEATTRIBUTES);
Icon ico = Icon.FromHandle(sfi.hIcon);
// Test displaying icon on desktop
using (Graphics gr = Graphics.FromHwnd(IntPtr.Zero))
{
    gr.DrawIcon(ico, 50, 50);
}

with declarations :

public const int SHGFI_ICON = 0x100;  // Get icon
public const int SHGFI_DISPLAYNAME = 0x200;  // Get display name
public const int SHGFI_TYPENAME = 0x400;  // Get type name
public const int SHGFI_ATTRIBUTES = 0x800;  // Get attributes
public const int SHGFI_ICONLOCATION = 0x1000;  // Get icon location
public const int SHGFI_EXETYPE = 0x2000;  // Return exe type
public const int SHGFI_SYSICONINDEX = 0x4000;  // Get system icon index
public const int SHGFI_LINKOVERLAY = 0x8000;  // put a link overlay On icon
public const int SHGFI_SELECTED = 0x10000;  // Show() icon In selected state
public const int SHGFI_ATTR_SPECIFIED = 0x20000; // Get only specified attributes

public const int SHGFI_LARGEICON = 0x0; // Get large icon
public const int SHGFI_SMALLICON = 0x1; // Get small icon
public const int SHGFI_OPENICON = 0x2; // Get open icon
public const int SHGFI_SHELLICONSIZE = 0x4; // Get shell size icon
public const int SHGFI_PIDL = 0x8; // pszPath Is a pidl
public const int SHGFI_USEFILEATTRIBUTES = 0x10; // use passed dwFileAttribute
public const int SHGFI_ADDOVERLAYS = 0x20; // apply the appropriate overlays
public const int SHGFI_OVERLAYINDEX = 0x40; // Get the index Of the overlay in the upper 8 bits of the iIcon

[StructLayout(LayoutKind.Sequential)]
public struct SHFILEINFO
{
    public IntPtr hIcon;
    public int iIcon;
    public int dwAttributes;
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 260)]
    public string szDisplayName;
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 80)]
    public string szTypeName;
}

[DllImport("Shell32.dll", SetLastError = true, CharSet = CharSet.Auto)]
public static extern IntPtr SHGetFileInfo(string pszPath, uint dwFileAttributes, ref SHFILEINFO psfi, uint cbFileInfo, uint uFlags);

Answer 2

Have you considered using the Visual Studio Image Library?

Answer 3

@RLWA32 : There are nicer icons:

The txt icon is from EditPlus, my favorite (text) editor.