Environment: VC#.NET
How to Use the SHGetFileInfo Function to Get the Icons That Are Associated with Files in Visual C# .NET
Summary
This step-by-step article describes how to use the SHGetFileInfo function to get the icons that are associated with files.
Create a Windows Forms Application
- Start Microsoft Visual Studio .NET.
- On the File menu, point to New, and then click Project.
- In the New Project dialog box, click Visual C# Projects under Project Types, and then click Windows Application under Templates.
- In the Name box, type GetIconSample.
Use the SHGetFileInfo Function
- Add the following code in the Form1.cs file at the end of the USING statements:
- Add the following code at the beginning of the GetIconSample namespace:
- Add the following code in the Form1 class after the PRIVATE statements:
- Add a listView control, a button control, and an imageList control to the form. The default names are listView1, button1, and imageList1, respectively.
- In the Properties window of button1, set the button text to Select a File, and then add the following code in the button1_click event:
using System.Runtime.InteropServices;
[StructLayout(LayoutKind.Sequential)] public struct SHFILEINFO { public IntPtr hIcon; public IntPtr iIcon; public uint dwAttributes; [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 260)] public string szDisplayName; [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 80)] public string szTypeName; }; class Win32 { public const uint SHGFI_ICON = 0x100; public const uint SHGFI_LARGEICON = 0x0; // 'Large icon public const uint SHGFI_SMALLICON = 0x1; // 'Small icon [DllImport("shell32.dll")] public static extern IntPtr SHGetFileInfo(string pszPath, uint dwFileAttributes, ref SHFILEINFO psfi, uint cbSizeFileInfo, uint uFlags); }
private int nIndex = 0;
IntPtr hImgSmall; //the handle to the system image list IntPtr hImgLarge; //the handle to the system image list string fName; // 'the file name to get icon from SHFILEINFO shinfo = new SHFILEINFO(); OpenFileDialog openFileDialog1 = new OpenFileDialog(); openFileDialog1.InitialDirectory = "c:\temp\"; openFileDialog1.Filter = "All files (*.*)|*.*"; openFileDialog1.FilterIndex = 2; openFileDialog1.RestoreDirectory = true ; listView1.SmallImageList = imageList1; listView1.LargeImageList = imageList1; if(openFileDialog1.ShowDialog() == DialogResult.OK) { fName = openFileDialog1.FileName; //Use this to get the small Icon hImgSmall = Win32.SHGetFileInfo(fName, 0, ref shinfo, (uint)Marshal.SizeOf(shinfo), Win32.SHGFI_ICON | Win32.SHGFI_SMALLICON); //Use this to get the large Icon //hImgLarge = SHGetFileInfo(fName, 0, //ref shinfo, (uint)Marshal.SizeOf(shinfo), //Win32.SHGFI_ICON | Win32.SHGFI_LARGEICON); //The icon is returned in the hIcon member of the shinfo //struct System.Drawing.Icon myIcon = System.Drawing.Icon.FromHandle(shinfo.hIcon); imageList1.Images.Add(myIcon); //Add file name and icon to listview listView1.Items.Add(fName, nIndex++); }
Run the Project
- Compile the project: On the Build menu, click Build Solution.
- Press F5 to run the project.
- Click Select a File, and then select a file in the Open dialog box. The name of the file and the icon that is associated with the file appear in the ListView control.