Update an image control as soon as a file is selected in File Upload control in ASP.NET

I have an image control and a file upload control in .NET 2.0 (VS.NET 2008) form. As soon as user selects an image file in the file upload control, i want the image to appear in the image control of the form. What would be the way to do this ?

(The only event File Upload seems to support is 'OnChange'开发者_开发知识库 and i don't know enough javascript to update Image1.URL based on content of FileUpload).

Thanks, Chak.

---

You need to upload Asynchronously , and you could try AJAX AsyncFileUpload and this is what you are looking... http://asp.net-informations.com/ajax/ajax-AsyncFileUpload.htm

---

Are you looking for a kind of preview? You can only show the image to the user after the file has been uploaded. I'm pretty sure the user has to actively do so (otherwise you could try to read the entire filesystem from the browser)

---

I think this is a good example:

http://www.codeproject.com/KB/ajax/AJAXUpload.aspx

this is a good starting point too:

http://www.eggheadcafe.com/community/aspnet/2/10204276/how-to-display-image-when-upload-image.aspx

or here:

http://www.eggheadcafe.com/community/aspnet/2/10236947/image-upload-and-display.aspx

updated

  protected void Button4_Click(object sender, EventArgs e)
    {
        string strExtn;
        string strpostedfile;

        strpostedfile = fileuploading.PostedFile.FileName;
        strExtn = System.IO.Path.GetExtension(strpostedfile);
        strExtn = strExtn.ToLower();

        string strEx = Path.GetExtension(fileuploading.PostedFile.FileName).ToLower();
        String filename = Path.GetFileName(fileuploading.FileName);
        filename = filename.Remove(filename.Length - strEx.Length);

        fileuploading.SaveAs(Server.MapPath("~/Photos/") + filename);
        uploadImage.ImageUrl = "~/Photos/" + filename;

    }

Page:

  <asp:FileUpload ID="fileuploading" runat="server" />
<asp:Button ID="Button4" runat="server" onclick="Button4_Click" Text="Button" />
<br />
<asp:Image ID="uploadImage" runat="server" />