private void tsbSave_Click(object sender, EventArgs e)
{
if (txtBookTypeName.Text == "")
{
this.showErrorMessage("ป้อนประเภทหนังสือก่อน");
return;
}
if (labBookTypeID.Text != "")
{
this.showErrorMessage("คุณกำลังแก้ไขหรือลบข้อมูล");
return;
}
BookType booktype = new BookType();
booktype.BookTypeName = txtBookTypeName.Text;
booktype.create();
this.showDgvBookType();
this.clear();
}