Search
Module:
Directory

   Desktop Functions:

   Smart Device Functions:


Show Recent Changes
Subscribe (RSS)
Misc. Pages
Comments
FAQ
Helpful Tools
Playground
Suggested Reading
Website TODO List
Download Visual Studio Add-In

CreateIconFromResource (user32)
 
.
Summary
Summary

C# Signature:

[DllImport("user32.dll")]
static extern IntPtr CreateIconFromResourceEx(byte [] pbIconBits, uint cbIconBits, bool fIcon, uint dwVersion, int cxDesired, int cyDesired, uint uFlags);
static extern IntPtr CreateIconFromResource(byte[] presbits, uint dwResSize, bool fIcon, uint dwVer);

VB.NET Signature:

<DllImport("user32.dll")> _
Private Shared Function CreateIconFromResourceEx(pbIconBits As Byte(), cbIconBits As UInteger, fIcon As Boolean, dwVersion As UInteger, cxDesired As Integer, cyDesired As Integer, uFlags As UInteger) As IntPtr
End Function
[DllImport("user32.dll")]
static extern IntPtr CreateIconFromResource(IntPtr presbits, int dwResSize, bool fIcon, int dwVer);

User-Defined Types:

None.

VB.NET Signature:

<DllImport("user32.dll")> _
Private Shared Function CreateIconFromResource(presbits As Byte(), dwResSize As UInteger, fIcon As Boolean, dwVer As UInteger) As IntPtr
End Function

Notes:

None.

User-Defined Types:

Existing Methods Modified

Tips & Tricks:

Please add some!

Notes:

Awesome Example, Powerful and Accurate Representation

Sample Code:

Please add some!

Yvan say this about this example:

Why I posted this example: I looked and found no working examples

I modified what I found to get a working example, this works ok

Alternative Managed API:

Do you know one? Please contribute it!

This is not a complete invention of the class, simply a working example I produced !!!

Documentation

Tips & Tricks:

See below for 3 examples loaded & embedded mouse cursors examples

Sample Code:

added by Yvan Genesse

Example 3 by TOM_RUS

Alternative Managed API:

Solved by Yvan Genesse Nov. 28, 2010

Documentation

Example 1

// used for loading animated mouse cursors from file loading example provided below
// in my new improved class AdvancedCursorsFromEmbededResources

// this is a previously known released class item
/*
    // in your form C#
    try
    {
        // from file
        this.Cursor = AdvancedCursors.Create(Path.Combine(Application.StartupPath, "flower_anim.ani"));
    }
    catch (Exception err)
    {
        MessageBox.Show(err.Message);
    }
*/


public class AdvancedCursors
{
    [DllImport("User32.dll")]
    private static extern IntPtr LoadCursorFromFile(String str);

    public static Cursor Create(string filename)
    {
        IntPtr hCursor = LoadCursorFromFile(filename);

        if (!IntPtr.Zero.Equals(hCursor))
        {
            return new Cursor(hCursor);
        }
        else
        {
            throw new ApplicationException("Could not create cursor from file " + filename);
        }
    }
}

Example 2

// from resources   modification here is :   byte[] variable resource in the call
// modified class by Yvan Genesse
public class AdvancedCursorsFromEmbededResources
{
    // modified by Yvan Genesse November 29 2010

    // C# example tested in MS Visual Studio 2010 Ultimate version
    // University Student in E-Business @ Laurentian University

    // in your form code
/*
    try
    {
        // from file
        //this.Cursor = AdvancedCursors.Create(Path.Combine(Application.StartupPath, "flower_anim.ani"));
        // from resouces   modification here is :   byte[] resource in the call
        byte[] Embeded_Cursor_Resource = Properties.Resources.flower_anim;  // the animate cursor desired
        this.Cursor = AdvancedCursorsFromEmbededResources.Create(Embeded_Cursor_Resource);

        // or this way also works
        this.Cursor = AdvancedCursorsFromEmbededResources.Create(Properties.Resources.flower_anim);
    }
    catch (Exception err)
    {
        MessageBox.Show(err.Message);
    }
*/

    [DllImport("user32.dll")]
    static extern IntPtr CreateIconFromResource(byte[] presbits, uint dwResSize, bool fIcon, uint dwVer);

    // modification here is :   byte[] resource in the call      
    public static Cursor Create( byte[] resource)
    {
        IntPtr myNew_Animated_hCursor;

        //byte[] resource = Properties.Resources.flower_anim;

        myNew_Animated_hCursor = CreateIconFromResource(resource, (uint)resource.Length, false, 0x00030000);

        if (!IntPtr.Zero.Equals(hCursor))
        {
            // all is good
            return new Cursor(myNew_Animated_hCursor);
        }
        else
        {
            // resource wrong type or memory error occurred
            // normally this resource exists since you had to put  Properties.Resources. and a resource would appear and you selected it
            // the animate cursor desired  is the error generator since this call is not required for simple cursors

            throw new ApplicationException("Could not create cursor from Embedded resource ");
        }        
    }    
}


Example 3 - Load *.cur file from resources, requires enabling unsafe code

using System;
using System.Runtime.InteropServices;
using System.Windows.Forms;

namespace EmbedCursorTest
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            byte[] cross_i = Properties.Resources.cross_i; // *.cur file embedded into resources

            this.Cursor = cross_i.CursorFromArray(0);
        }
    }

    public static class Extensions
    {
        [StructLayout(LayoutKind.Explicit, Pack = 1)]
        struct IconHeader
        {
            [FieldOffset(0)]
            public short reserved;
            [FieldOffset(2)]
            public short type;
            [FieldOffset(4)]
            public short count;
        }

        [StructLayout(LayoutKind.Explicit, Pack = 1)]
        struct IconInfo
        {
            [FieldOffset(0)]
            public byte width;
            [FieldOffset(1)]
            public byte height;
            [FieldOffset(2)]
            public byte colors;
            [FieldOffset(3)]
            public byte reserved;
            [FieldOffset(4)]
            public short planes; // ICO file
            [FieldOffset(6)]
            public short bpp; // ICO file
            [FieldOffset(4)]
            public short hotspot_x; // CUR file
            [FieldOffset(6)]
            public short hotspot_y; // CUR file
            [FieldOffset(8)]
            public int size;
            [FieldOffset(12)]
            public int offset;
        }

        [DllImport("user32.dll", SetLastError = true)]
        static extern IntPtr CreateIconFromResource(IntPtr pbIconBits, int dwResSize, bool fIcon, int dwVer);

        public static unsafe Cursor CursorFromArray(this byte[] data, int imageIndex)
        {
            fixed (byte* pData = data)
            {
                IconHeader* iHeader = (IconHeader*)pData;

                if (imageIndex > iHeader->count - 1)
                    throw new ArgumentOutOfRangeException("imageIndex");

                IconInfo* iInfo = (IconInfo*)(pData + sizeof(IconHeader) + imageIndex * sizeof(IconInfo));

                IntPtr iconImage = Marshal.AllocHGlobal(iInfo->size + 4);
/*wiki bug*/    *(short*)(iconImage + 0) = iInfo->hotspot_x;
/*wiki bug*/    *(short*)(iconImage + 2) = iInfo->hotspot_y;
                Marshal.Copy(data, iInfo->offset, iconImage + 4, iInfo->size);

                IntPtr hCursor = CreateIconFromResource(iconImage, iInfo->size + 4, false, 0x30000);
                Marshal.FreeHGlobal(iconImage);

                return new Cursor(hCursor);
            }
        }

        // same as above, but without pointers
        public static Cursor CursorFromArrayManaged(this byte[] data, int imageIndex)
        {
            GCHandle handle = GCHandle.Alloc(data, GCHandleType.Pinned);

            IconHeader iHeader = (IconHeader)Marshal.PtrToStructure(handle.AddrOfPinnedObject(), typeof(IconHeader));

            if (imageIndex > iHeader.count - 1)
            {
                handle.Free();
                throw new ArgumentOutOfRangeException("imageIndex");
            }

            IntPtr iconInfoPtr = handle.AddrOfPinnedObject() + Marshal.SizeOf(typeof(IconHeader)) + imageIndex * Marshal.SizeOf(typeof(IconInfo));
            IconInfo iInfo = (IconInfo)Marshal.PtrToStructure(iconInfoPtr, typeof(IconInfo));

            handle.Free();

            IntPtr iconImage = Marshal.AllocHGlobal(iInfo.size + 4);
            Marshal.WriteInt16(iconImage + 0, iInfo.hotspot_x);
            Marshal.WriteInt16(iconImage + 2, iInfo.hotspot_y);
            Marshal.Copy(data, iInfo.offset, iconImage + 4, iInfo.size);

            IntPtr hCursor = CreateIconFromResource(iconImage, iInfo.size + 4, false, 0x30000);
            Marshal.FreeHGlobal(iconImage);
            return new Cursor(hCursor);
        }
    }
}

Please edit this page!

Do you have...

  • helpful tips or sample code to share for using this API in managed code?
  • corrections to the existing content?
  • variations of the signature you want to share?
  • additional languages you want to include?

Select "Edit This Page" on the right hand toolbar and edit it! Or add new pages containing supporting types needed for this API (structures, delegates, and more).

 
Access PInvoke.net directly from VS:
Terms of Use
Edit This Page
Find References
Show Printable Version
Revisions