How to get file icon in C#

This article will introduce to you how to obtain the association icon of a file? The summary is now as follows:

First, clarify the problem: get the associated icon of a file or the display icon of a certain type of file.

After searching online, I found that there are still many methods, but there are not many methods to obtain using C#. I chose a method that uses the .Net library.

Classes used:

, located in the namespace.

Specific methods:

Static method in class: public static Icon ExtractAssociatedIcon(string filePath)

This method receives a file path and returns an object of type Icon. This object is both the Icon icon object of the specified file.

This Icon class provides a Save method that allows you to write Icon files to a stream and then save them to a hard disk file.

Of course, it is also OK to display it in the program. The Icon class provides the ToBitmap method, which can convert the Icon file into a Bitmap. Bitmap can be displayed in PictureBox.

What should I do if I want to get the file icon based on the suffix name? I thought of a stupid method. Look at the code ~

string fileName = "tmp." + houz*g;
(fileName).Close();
Image img = (fileName).ToBitmap();
(fileName);

In this way, create a new file with a specified suffix name, and delete it directly after obtaining the icon, and you can get the icon with a specified file suffix name. Hehehe~

Below is a code introduction to C# obtain file association icon

using System;
using ;
using ;
using ;
using ;
using Microsoft.Win32;
namespace 
{
class SystemIcon
{
[StructLayout(, CharSet = )]
public struct SHFILEINFO
{
public IntPtr hIcon;
public int iIcon;
public uint dwAttributes;
[MarshalAs(, SizeConst = 260)]
public string szDisplayName;
[MarshalAs(, SizeConst = 80)]
public string szTypeName;
}
[DllImport("", EntryPoint = "SHGetFileInfo", SetLastError = true, CharSet = )]
public static extern IntPtr SHGetFileInfo(string pszPath, uint dwFileAttributes, ref SHFILEINFO psfi, uint cbFileInfo, uint uFlags);
[DllImport("", EntryPoint = "DestroyIcon")]
public static extern int DestroyIcon(IntPtr hIcon);
#region API parameters constant definitionpublic enum FileInfoFlags : uint
{
SHGFI_ICON = 0x000000100, // get icon
SHGFI_DISPLAYNAME = 0x000000200, // get display name
SHGFI_TYPENAME = 0x000000400, // get type name
SHGFI_ATTRIBUTES = 0x000000800, // get attributes
SHGFI_ICONLOCATION = 0x000001000, // get icon location
SHGFI_EXETYPE = 0x000002000, // return exe type
SHGFI_SYSICONINDEX = 0x000004000, // get system icon index
SHGFI_LINKOVERLAY = 0x000008000, // put a link overlay on icon
SHGFI_SELECTED = 0x000010000, // show icon in selected state
SHGFI_ATTR_SPECIFIED = 0x000020000, // get only specified attributes
SHGFI_LARGEICON = 0x000000000, // get large icon
SHGFI_SMALLICON = 0x000000001, // get small icon
SHGFI_OPENICON = 0x000000002, // get open icon
SHGFI_SHELLICONSIZE = 0x000000004, // get shell size icon
SHGFI_PIDL = 0x000000008, // pszPath is a pidl
SHGFI_USEFILEATTRIBUTES = 0x000000010, // use passed dwFileAttribute
SHGFI_ADDOVERLAYS = 0x000000020, // apply the appropriate overlays
SHGFI_OVERLAYINDEX = 0x000000040 // Get the index of the overlay
}
public enum FileAttributeFlags : uint
{
FILE_ATTRIBUTE_READONLY = 0x00000001,
FILE_ATTRIBUTE_HIDDEN = 0x00000002,
FILE_ATTRIBUTE_SYSTEM = 0x00000004,
FILE_ATTRIBUTE_DIRECTORY = 0x00000010,
FILE_ATTRIBUTE_ARCHIVE = 0x00000020,
FILE_ATTRIBUTE_DEVICE = 0x00000040,
FILE_ATTRIBUTE_NORMAL = 0x00000080,
FILE_ATTRIBUTE_TEMPORARY = 0x00000100,
FILE_ATTRIBUTE_SPARSE_FILE = 0x00000200,
FILE_ATTRIBUTE_REPARSE_POINT = 0x00000400,
FILE_ATTRIBUTE_COMPRESSED = 0x00000800,
FILE_ATTRIBUTE_OFFLINE = 0x00001000,
FILE_ATTRIBUTE_NOT_CONTENT_INDEXED = 0x00002000,
FILE_ATTRIBUTE_ENCRYPTED = 0x00004000
}
#endregion
/// &lt;summary&gt;
/// Get the associated icon for file type/// &lt;/summary&gt;
/// <param name="fileName">Extension of file type or absolute path to file</param>/// <param name="isLargeIcon">Whether to return the large icon</param>/// <returns>Getted icon</returns>public static Icon GetIcon(string fileName, bool isLargeIcon)
{
SHFILEINFO shfi = new SHFILEINFO();
IntPtr hI;
if (isLargeIcon)
hI = SHGetFileInfo(fileName, 0, ref shfi, (uint)(shfi), (uint)FileInfoFlags.SHGFI_ICON | (uint)FileInfoFlags.SHGFI_USEFILEATTRIBUTES | (uint)FileInfoFlags.SHGFI_LARGEICON);
else
hI = SHGetFileInfo(fileName, 0, ref shfi, (uint)(shfi), (uint)FileInfoFlags.SHGFI_ICON | (uint)FileInfoFlags.SHGFI_USEFILEATTRIBUTES | (uint)FileInfoFlags.SHGFI_SMALLICON);
Icon icon = ().Clone() as Icon;
DestroyIcon(); //Release resourcesreturn icon;
}
/// &lt;summary&gt; 
/// Get folder icon/// &lt;/summary&gt; 
/// <returns>Icon</returns>public static Icon GetDirectoryIcon(bool isLargeIcon)
{
SHFILEINFO _SHFILEINFO = new SHFILEINFO();
IntPtr _IconIntPtr;
if (isLargeIcon)
{
_IconIntPtr = SHGetFileInfo(@"", 0, ref _SHFILEINFO, (uint)(_SHFILEINFO), ((uint)FileInfoFlags.SHGFI_ICON | (uint)FileInfoFlags.SHGFI_LARGEICON));
}
else
{
_IconIntPtr = SHGetFileInfo(@"", 0, ref _SHFILEINFO, (uint)(_SHFILEINFO), ((uint)FileInfoFlags.SHGFI_ICON | (uint)FileInfoFlags.SHGFI_SMALLICON));
}
if (_IconIntPtr.Equals()) return null;
Icon _Icon = (_SHFILEINFO.hIcon);
return _Icon;
}
}
}