Using jQuery with ASP.Net to swap images.

Using jQuery with ASP.Net to swap images.

I am using jQuery with ASP.Net and VB.Net.
I have an Upload control on the page where user selects an image to upload. After user selects the image, I would like a preview of the image to show up beside the upload control. The image control already exists and has visibilty. However, there's no src. It's blank. Image is an ASP.Net control, while upload is an HTML element. The function below gets called on the File Upload control's OnChange event.
So far what I have is this:

            function changeSrc() {
                var img1 = $('#<%=img1.ClientId%>');
                var file = $('#fileUpload');
                var src = file.value;
                var path = $('#fileUpload.FileName');
                img1.src = path;
  }
I know there's something I'm doing wrong. Please let me know. Thanks.