2021-03-21 22:34:17 +01:00

109 lines
4.1 KiB
C#

/*
* Greenshot - a free and open source screenshot tool
* Copyright (C) 2007-2021 Thomas Braun, Jens Klingen, Robin Krom
*
* For more information see: http://getgreenshot.org/
* The Greenshot project is hosted on GitHub https://github.com/greenshot/greenshot
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 1 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
using System;
using System.Drawing;
using System.Runtime.InteropServices;
using System.IO;
namespace GreenshotPlugin.UnmanagedHelpers {
/// <summary>
/// Description of Shell32.
/// </summary>
public static class Shell32 {
[DllImport("shell32", CharSet = CharSet.Unicode)]
public static extern int ExtractIconEx(string sFile, int iIndex, out IntPtr piLargeVersion, out IntPtr piSmallVersion, int amountIcons);
[DllImport("shell32", CharSet = CharSet.Unicode)]
private static extern IntPtr SHGetFileInfo(string pszPath, uint dwFileAttributes, ref SHFILEINFO psfi, uint cbFileInfo, uint uFlags);
[StructLayout(LayoutKind.Sequential, CharSet=CharSet.Unicode)]
private struct SHFILEINFO {
public readonly IntPtr hIcon;
public readonly int iIcon;
public readonly uint dwAttributes;
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 260)]
public readonly string szDisplayName;
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 80)]
public readonly string szTypeName;
};
// Browsing for directory.
private const uint SHGFI_ICON = 0x000000100; // get icon
private const uint SHGFI_LINKOVERLAY = 0x000008000; // put a link overlay on icon
private const uint SHGFI_LARGEICON = 0x000000000; // get large icon
private const uint SHGFI_SMALLICON = 0x000000001; // get small icon
private const uint SHGFI_USEFILEATTRIBUTES = 0x000000010; // use passed dwFileAttribute
private const uint FILE_ATTRIBUTE_NORMAL = 0x00000080;
/// <summary>
/// Options to specify the size of icons to return.
/// </summary>
public enum IconSize {
/// <summary>
/// Specify large icon - 32 pixels by 32 pixels.
/// </summary>
Large = 0,
/// <summary>
/// Specify small icon - 16 pixels by 16 pixels.
/// </summary>
Small = 1
}
/// <summary>
/// Returns an icon for a given file extension - indicated by the name parameter.
/// See: http://msdn.microsoft.com/en-us/library/windows/desktop/bb762179(v=vs.85).aspx
/// </summary>
/// <param name="filename">Filename</param>
/// <param name="size">Large or small</param>
/// <param name="linkOverlay">Whether to include the link icon</param>
/// <returns>System.Drawing.Icon</returns>
public static Icon GetFileIcon(string filename, IconSize size, bool linkOverlay) {
SHFILEINFO shfi = new SHFILEINFO();
// SHGFI_USEFILEATTRIBUTES makes it simulate, just gets the icon for the extension
uint flags = SHGFI_ICON | SHGFI_USEFILEATTRIBUTES;
if (linkOverlay) {
flags += SHGFI_LINKOVERLAY;
}
// Check the size specified for return.
if (IconSize.Small == size) {
flags += SHGFI_SMALLICON;
} else {
flags += SHGFI_LARGEICON;
}
SHGetFileInfo(Path.GetFileName(filename), FILE_ATTRIBUTE_NORMAL, ref shfi, (uint)Marshal.SizeOf(shfi), flags);
// Only return an icon if we really got one
if (shfi.hIcon != IntPtr.Zero) {
// Copy (clone) the returned icon to a new object, thus allowing us to clean-up properly
Icon icon = (Icon)Icon.FromHandle(shfi.hIcon).Clone();
// Cleanup
User32.DestroyIcon(shfi.hIcon);
return icon;
}
return null;
}
}
}