图片上传（在textarea中显示）

protected void btnupload_Click(object sender, EventArgs e)
        {
            
            if (File1.PostedFile.ContentType.ToUpper().IndexOf("IMAGE") > -1)
            {
                System.Drawing.Image img = System.Drawing.Image.FromStream(File1.PostedFile.InputStream);
                int Width = img.Width;
                int Height = img.Height;
                if (Width > 60 || Height > 60 || File1.PostedFile.ContentLength > 1024 * 1024 * 2)
                {
                    
                    Label3.Text = "温馨提示：你上传的头像尺寸不符合要求，请重新选择图片（图片大小：60*60）！";
                }
                else
                {
                    string sPath = Server.MapPath(System.DateTime.Now.ToString("yyy-MM-dd") + Session.SessionID + ".jpg");
                    this.File1.PostedFile.SaveAs(sPath);

                    Label3.Text = "恭喜你，头像上传成功！";
                }  
            }
            else
            {
                Response.Write("请选择图片文件!");
            }

            string filename = this.File1.PostedFile.FileName;

            filename = DateTime.Now.Ticks.ToString() + filename.Substring(filename.LastIndexOf("."));
            this.File1.PostedFile.SaveAs(Server.MapPath("upload") + "\\" + filename);

            // Page.ClientScript.RegisterStartupScript(this.GetType(), "asdf", "alert('您上传的图片太大了')", true);

            StringBuilder sb = new StringBuilder();
           
            content1.InnerHtml += sb.Append("<img src=\"upload/" + filename + "\" />").ToString();
        }