C# Code to Upload File in document library

protected void BtnSaveCauseImage_Click(object sender, EventArgs e)

        {

            if (this.FileUploadCause.PostedFile != null)

            {

                SPSecurity.RunWithElevatedPrivileges(delegate()

                {

                    using (SPSite enterprisesite = new SPSite(this.ArtcleListUrl))

                    {

                        using (SPWeb enterprisesiteweb = enterprisesite.OpenWeb())

                        {

                            SPList ArticleImageslist = enterprisesiteweb.Lists["ArticleImages"];

                            enterprisesite.AllowUnsafeUpdates = true;

                            enterprisesiteweb.AllowUnsafeUpdates = true;

                            SPListItem Items = ArticleImageslist.Items.Add();

                            if (this.FileUploadCause.PostedFile.ContentLength > 0)

                            {

                                int ImgFileSize = this.FileUploadCause.PostedFile.ContentLength;

                                System.IO.Stream strm = this.FileUploadCause.PostedFile.InputStream;

                                byte[] byt = new byte[Convert.ToInt32(this.FileUploadCause.PostedFile.ContentLength)];

                                strm.Read(byt, 0, Convert.ToInt32(this.FileUploadCause.PostedFile.ContentLength));

                                strm.Close();

                                string Imgfilename = System.IO.Path.GetFileName(this.FileUploadCause.PostedFile.FileName);

                                if (Imgfilename.Contains("."))

                                {

                                    string[] delim1 = new string[1];

                                    delim1[0] = ".";

                                    string[] strName = Imgfilename.Split(delim1, StringSplitOptions.RemoveEmptyEntries);

                                    string strFile = strName[0];

                                    strFile = DateTime.Now.ToString() + "" + strFile;

                                    strFile = strFile.Replace("/", "-").Replace(":", "-").Replace(" ", "");

                                    Imgfilename = strFile + "." + strName[1];

                                }

                                ArticleImageslist.RootFolder.Files.Add(Imgfilename, byt);

                                string ImagePath = ArtcleListUrl + "ArticleImages/" + Imgfilename;

                                //string strCause = txtCause.Text + "<img src=" + ImagePath + " width=" + "\"100\"" + " " + "height=" + "\"100\">";

                                string strCause = txtCause.Text + "<img src=" + ImagePath + ">";

                                txtCause.Text = strCause;

                            }

                            enterprisesite.AllowUnsafeUpdates = true;

                            enterprisesiteweb.AllowUnsafeUpdates = true;

                        }

                    }

                });

            }

        }