Setting the filter to an OpenFileDialog to allow the typical image formats?

Question

From the docs, the filter syntax that you need is as follows:

Office Files|*.doc;*.xls;*.ppt

i.e. separate the multiple extensions with a semicolon -- thus, Image Files|*.jpg;*.jpeg;*.png;....

Here's an example of the ImageCodecInfo suggestion (in VB):

   Imports System.Drawing.Imaging
        ...            

        Dim ofd as new OpenFileDialog()
        ofd.Filter = ""
        Dim codecs As ImageCodecInfo() = ImageCodecInfo.GetImageEncoders()
        Dim sep As String = String.Empty
        For Each c As ImageCodecInfo In codecs
            Dim codecName As String = c.CodecName.Substring(8).Replace("Codec", "Files").Trim()
            ofd.Filter = String.Format("{0}{1}{2} ({3})|{3}", ofd.Filter, sep, codecName, c.FilenameExtension)
            sep = "|"
        Next
        ofd.Filter = String.Format("{0}{1}{2} ({3})|{3}", ofd.Filter, sep, "All Files", "*.*")

And it looks like this:

Complete solution in C# is here:

private void btnSelectImage_Click(object sender, RoutedEventArgs e)
{
    // Configure open file dialog box 
    Microsoft.Win32.OpenFileDialog dlg = new Microsoft.Win32.OpenFileDialog();
    dlg.Filter = "";

    ImageCodecInfo[] codecs = ImageCodecInfo.GetImageEncoders();
    string sep = string.Empty;

    foreach (var c in codecs)
    {
       string codecName = c.CodecName.Substring(8).Replace("Codec", "Files").Trim();
       dlg.Filter = String.Format("{0}{1}{2} ({3})|{3}", dlg.Filter, sep, codecName, c.FilenameExtension);
       sep = "|";
    }

    dlg.Filter = String.Format("{0}{1}{2} ({3})|{3}", dlg.Filter, sep, "All Files", "*.*"); 

    dlg.DefaultExt = ".png"; // Default file extension 

    // Show open file dialog box 
    Nullable<bool> result = dlg.ShowDialog();

    // Process open file dialog box results 
    if (result == true)
    {
       // Open document 
       string fileName  = dlg.FileName;
       // Do something with fileName  
    }
} 

To filter images files, use this code sample.

//Create a new instance of openFileDialog
OpenFileDialog res = new OpenFileDialog();

//Filter
res.Filter = "Image Files|*.jpg;*.jpeg;*.png;*.gif;*.tif;...";

//When the user select the file
if (res.ShowDialog() == DialogResult.OK)
{
   //Get the file's path
   var filePath = res.FileName;
   //Do something
   ....
}

I like Tom Faust's answer the best. Here's a C# version of his solution, but simplifying things a bit.

var codecs = ImageCodecInfo.GetImageEncoders(); 
var codecFilter = "Image Files|"; 
foreach (var codec in codecs) 
{
    codecFilter += codec.FilenameExtension + ";"; 
} 
dialog.Filter = codecFilter;

For images, you could get the available codecs from GDI (System.Drawing) and build your list from that with a little work. This would be the most flexible way to go.

ImageCodecInfo[] codecs = ImageCodecInfo.GetImageEncoders();