dynamic controls(linkbutton, placeholder) in webform

Hi

First, Please read the entire post before you provide answer...

I am trying to create a page with image upload. After the upload, a image thumbnail of the uploaded images are shown below the  file upload controls.

Here is what I am doing now...

 

    protected void Page_Load(object sender, EventArgs e)
    {

        if (Page.IsPostBack)
        {
            if (FileUploadPhoto.PostedFile != null)
            {
                AddImagePreviewControls();
            }
        }
    }

...
    protected void AddImagePreviewControls()
    {
        if (FileUploadPhoto.HasFile)
        {
            HiddenFieldPhotoCount.Value = Convert.ToString((Convert.ToInt32(HiddenFieldPhotoCount.Value)) + 1);
            String imageControlId = HiddenFieldPhotoCount.Value;
           
            PlaceHolder ph = new PlaceHolder();
            ph.ID = "PlaceHolderPhoto" + imageControlId;
           
            PanelPhotos.Controls.Add(ph);
            LinkButton lb = new LinkButton();
           
            lb.ID = "LinkButtonPhoto" + imageControlId;
            lb.Text = "delete";
            lb.Attributes.Add("OnClick", "DynamicLinkButtonPhoto_OnClick");
            PanelPhotos.Controls.Add(lb);
           
        }
    }
...
// an on_click event has code to upload the photos & other required stuff after which i call a method to set values for created controls, the method shown below
    protected void SetImagePreview(String iName)
    {
        String imageControlId = HiddenFieldPhotoCount.Value;
        PlaceHolder currentPH = (PlaceHolder)WizardNewProfile.FindControl("PlaceHolderPhoto" + imageControlId);
        LinkButton currentLB = (LinkButton)WizardNewProfile.FindControl("LinkButtonPhoto" + imageControlId);
        String iUrl = Request.ApplicationPath.ToString() + "/Photos/folder/" + iName;
        currentPH.Controls.Add(new LiteralControl("<img src=\"" + iUrl + "\" width=\"50px\" />"));
        currentLB.CommandArgument = iName;
    }

 

What happens is that though everything works fine, on postback, the image(placeholder) and linkbutton disappears.

 
What am I doing wrong? please guide me...
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