[c#] Open file dialog and select a file using WPF controls and C#

I have a TextBox named textbox1 and a Button named button1. When I click on button1 I want to browse my files to search only for image files (type jpg, png, bmp...). And when I select an image file and click Ok in the file dialog I want the file directory to be written in the textbox1.text like this:

textbox1.Text = "C:\myfolder\myimage.jpg"

var ofd = new Microsoft.Win32.OpenFileDialog() {Filter = "JPEG Files (*.jpeg)|*.jpeg|PNG Files (*.png)|*.png|JPG Files (*.jpg)|*.jpg|GIF Files (*.gif)|*.gif"}; 
var result = ofd.ShowDialog();
if (result == false) return;
textBox1.Text = ofd.FileName;