protected void Page_Load(object sender, EventArgs e) { _copyBarcode = Request.QueryString["barcode"]; _isNew = Convert.ToBoolean(Request.QueryString["isNew"]); _isbn = Request.QueryString["isbn"]; txtBarcode.Enabled = false; if (!Page.IsPostBack) { FillDropDowns(); if (_copyBarcode != null) { var bookCopyCollection = new BookCopyCollection(); if (bookCopyCollection.BookCopy.Find(_copyBarcode)) { DisplayCopyDetails(bookCopyCollection.BookCopy); } } if (_isNew) { var idGen = new IdGenerator(); txtBarcode.Text = idGen.BookCopy(); } } }