C# Signature:
[DllImport("shell32.dll", CharSet=CharSet.Auto)]
static extern uint ExtractIconEx(string szFileName, int nIconIndex,
IntPtr[] phiconLarge, IntPtr[] phiconSmall, uint nIcons);
VB Signature:
<DllImport("shell32.dll", CharSet:=CharSet.Auto)> _
Shared Function ExtractIconEx(ByVal szFileName As String, _
ByVal nIconIndex As Integer, _
ByVal phiconLarge() As IntPtr, _
ByVal phiconSmall() As IntPtr, _
ByVal nIcons As UInteger) As UInteger
End Function
VB 6 Signature:
Declare Function ExtractIconEx _
Lib "shell32.dll" _
Alias "ExtractIconExA" _
(ByVal lpszFile As String, _
ByVal nIconIndex As Integer, _
ByRef phiconLarge As Integer, _
ByRef phiconSmall As Integer, _
ByVal nIcons As Long) As Integer
User-Defined Types:
None.
Notes:
szFile
in A null-terminated string specifying the name of an executable file, DLL, or icon file from which icons will be extracted.
nIconIndex
in Specifies the zero-based index of the first icon to extract. For example, if this value is zero, the function extracts the first icon in the specified file.
If this value is –1 and phiconLarge and phiconSmall are both NULL, the function returns the total number of icons in the specified file. If the file is an executable file or DLL, the return value is the number of RT_GROUP_ICON resources. If the file is an .ico file, the return value is 1.
Windows 95/98/Me, Windows NT 4.0 and later: If this value is a negative number and either phiconLarge or phiconSmall is not NULL, the function begins by extracting the icon whose resource identifier is equal to the absolute value of nIconIndex. For example, use -3 to extract the icon whose resource identifier is 3.
phiconLarge
out Pointer to an array of icon handles that receives handles to the large icons extracted from the file. If this parameter is NULL, no large icons are extracted from the file.
phiconSmall
out Pointer to an array of icon handles that receives handles to the small icons extracted from the file. If this parameter is NULL, no small icons are extracted from the file.
nIcons
in Specifies the number of icons to extract from the file.
Tips & Tricks:
For Windows CE: import coredll.dll not shell32.dll
For Windows CE 2.10 and later: the nIconIndex parameter must be zero or –N, where N is a specified resource identifier. The nIcons parameter must be 1.
For Windows CE 1.0 through 2.10: the function returns the total number of icons in the specified file if nIconIndex is –1 and phIconLarge and phiconSmall are both NULL. If the file is an executable file or DLL, the return value is the number of RT_GROUP_ICON resources. If the file is an .ICO file, the return value is 1.
Sample Code:
namespace Martin.Hyldahl.Examples.ExtractIconEx
{
/*
* Example using ExtractIconEx
* Created by Martin Hyldahl (alanadin@post8.tele.dk)
* http://www.hyldahlnet.dk
*/
using System;
using System.Drawing;
using System.Runtime.InteropServices;
/// <summary>
/// Example using ExtractIconEx
/// </summary>
public class ExtractIconExample
{
/* CONSTRUCTORS */
static ExtractIconExample()
{
}
// HIDE INSTANCE CONSTRUCTOR
private ExtractIconExample()
{
}
[DllImport("Shell32", CharSet=CharSet.Auto)]
private static unsafe extern int ExtractIconEx (
string lpszFile,
int nIconIndex,
IntPtr[] phIconLarge,
IntPtr[] phIconSmall,
int nIcons);
[DllImport("user32.dll", EntryPoint="DestroyIcon", SetLastError=true)]
private static unsafe extern int DestroyIcon(IntPtr hIcon);
public static Icon ExtractIconFromExe(string file, bool large)
{
unsafe
{
int readIconCount = 0;
IntPtr[] hDummy = new IntPtr[1] {IntPtr.Zero};
IntPtr[] hIconEx = new IntPtr[1] {IntPtr.Zero};
try
{
if(large)
readIconCount = ExtractIconEx(file,0, hIconEx, hDummy, 1);
else
readIconCount = ExtractIconEx(file,0, hDummy, hIconEx, 1);
if(readIconCount > 0 && hIconEx[0] != IntPtr.Zero)
{
// GET FIRST EXTRACTED ICON
Icon extractedIcon = (Icon)Icon.FromHandle(hIconEx[0]).Clone();
return extractedIcon;
}
else // NO ICONS READ
return null;
}
catch(Exception ex)
{
/* EXTRACT ICON ERROR */
// BUBBLE UP
throw new ApplicationException("Could not extract icon", ex);
}
finally
{
// RELEASE RESOURCES
foreach(IntPtr ptr in hIconEx)
if(ptr != IntPtr.Zero)
DestroyIcon(ptr);
foreach(IntPtr ptr in hDummy)
if(ptr != IntPtr.Zero)
DestroyIcon(ptr);
}
}
}
}
}
Sample Code (VB Version of above):
Imports System.Runtime.InteropServices
Imports System.Drawing
Module IconExtract
<DllImport("shell32.dll", CharSet:=CharSet.Auto)> _
Function ExtractIconEx(ByVal szFileName As String, _
ByVal nIconIndex As Integer, _
ByVal phiconLarge() As IntPtr, _
ByVal phiconSmall() As IntPtr, _
ByVal nIcons As Integer) As Integer
End Function
<DllImport("user32.dll", EntryPoint:="DestroyIcon", SetLastError:=True)> _
Function DestroyIcon(ByVal hIcon As IntPtr) As Integer
End Function
Public Function WriteIconOut(ByVal iconsrcpath As String, ByVal icondestpath As String)
Dim iconsrc As Icon = ExtractIconFromExe(iconsrcpath, True)
iconsrc.Save(System.IO.File.OpenWrite(icondestpath))
End Function
Public Function ExtractIconFromExe(ByVal f As String, ByVal large As Boolean) As Icon
Dim readIconCount As Integer = 0
Dim hDummy As IntPtr() = New IntPtr(0) {IntPtr.Zero}
Dim hIconEx As IntPtr() = New IntPtr(0) {IntPtr.Zero}
Try
If (large) Then
readIconCount = ExtractIconEx(f, 0, hIconEx, hDummy, 1)
Else
readIconCount = ExtractIconEx(f, 0, hDummy, hIconEx, 1)
End If
If (readIconCount > 0 AndAlso Not hIconEx(0).Equals(IntPtr.Zero)) Then
' GET FIRST EXTRACTED ICON
Dim extractedIcon As Icon = Icon.FromHandle(hIconEx(0)).Clone()
Return extractedIcon
Else ' NO ICONS READ
Return Nothing
End If
Catch ex As Exception
' EXTRACT ICON ERROR
' BUBBLE UP
Throw New ApplicationException("Could not extract icon", ex)
Finally
'RELEASE RESOURCES
For Each ptr As IntPtr In hIconEx
If (Not ptr.Equals(IntPtr.Zero)) Then
DestroyIcon(ptr)
End If
Next ptr
For Each ptr As IntPtr In hDummy
If Not (ptr.Equals(IntPtr.Zero)) Then
DestroyIcon(ptr)
End If
Next ptr
End Try
End Function
End Module
Alternative Managed API:
Icon.ExtractAssociatedIcon(sFile)
