Help with opening image from listbox

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C#

let me explain what is my aim.
i would like to open whole folder of files in a listbox using the folderBrowserDialog. I am able to do that. But, i also want to select the file from the listbox itself and upon selecting, i need the image to appear in the picturebox.
Now, with my code below, i'm only able to open the folder and display all the files in the listbox. It's not able to appear a single image in the picturebox.
If u're not able to understand what i'm trying to say, please comment and let me know. Thank You:)

DialogResult results = folderBrowserDialog1.ShowDialog();
if (folderBrowserDialog1.ShowDialog() == DialogResult.OK)
{
     listBox1.Items.Clear(); //Clear items in listbox1
     string folderName = this.folderBrowserDialog1.SelectedPath;   //To browse folder
     DirectoryInfo dir = new DirectoryInfo(folderName);
     FileInfo[] fileInfo = dir.GetFiles("*.*");                    //Get only files in .jpg form if GetFiles("*.jpg")
     foreach (FileInfo f in fileInfo)
     {
         listBox1.Items.Add(f);  //add files from the folder into listbox1
     }
     pictureBox1.Image = Image.FromFile(openFileDialog1.FileName); //Returns an image object located at the path specified
}

error occurs at:
pictureBox1.Image = Image.FromFile(openFileDialog1.FileName); //Returns an image object located at the path specified

A Million Thanks!!
Cheers!! :)