错误的数据在回发时更新？

Question

我正在从数据库中检索数据到文本框，在更改文本框中的数据后，当我单击更新按钮时，再次上传相同的数据。这是获取数据的编码。

SqlConnection con = new SqlConnection("Data Source=ZAZIKHAN\\SQLEXPRESS;Initial Catalog=resume;Integrated Security=True");


    con.Open();
            SqlCommand cmd = new SqlCommand("select JobTitle,CompanyName,JobFrom,JobTo,Description,ExperienceType FROM Experience where eid=3", con);
            cmd.ExecuteNonQuery();
            SqlDataReader reader = cmd.ExecuteReader();
            if (reader.Read() && reader != null)
            {
                JobTitle.Text = reader["JobTitle"].ToString();
                CompanyName.Text = reader["CompanyName"].ToString();
                JobFrom.Text = reader["JobFrom"].ToString();
                JobTo.Text = reader["JobTo"].ToString();
                Description.InnerText = reader["Description"].ToString();
                ExperienceType.Text = reader["ExperienceType"].ToString();

            }
            reader.Close();
            con.Close();
        }
        catch (Exception ex)
        {
            Response.Write("<script LANGUAGE='JAVASCRIPT'>alert('" + ex + "')</script>");
        }

以下是更新数据的编码。

protected void UPDATE_Click(object sender, EventArgs e)
    {
        Response.Write("<script LANGUAGE='JAVASCRIPT'>alert('" + JobTitle.Text + "')</script>");
        try
        {
            SqlConnection con = new SqlConnection("Data Source=ZAZIKHAN\\SQLEXPRESS;Initial Catalog=resume;Integrated Security=True");
            con.Open();

            SqlCommand cmd3 = new SqlCommand("UPDATE Experience SET JobTitle ='" + JobTitle.Text + "',CompanyName ='" + CompanyName.Text + "',JobFrom ='" + DateTime.Now + "',JobTo = '" + JobTo.Text + "',Description ='" + Description.InnerText + "',ExperienceType='" + ExperienceType.Text + "' WHERE eid=3 ", con);
            if (cmd3.ExecuteNonQuery() == 1)
            {
                Response.Write("<script LANGUAGE='JavaScript' >alert('information saved Successful')</script>");
            }
            else { Response.Write("<script LANGUAGE='JavaScript' >alert('sorry try again')</script>"); }

            con.Close();
        }
        catch (Exception ex)
        {
            Response.Write("<script LANGUAGE='JAVASCRIPT'>alert('" + ex + "')</script>");
        }
    }