Question

我想编辑从数据库中读取的值。我的阅读代码是:(这可以在我的page_load中找到）

string uname = Session["ApplicantUsername1"].ToString();
txtUsername.Text = uname;

cs.Open();
SqlCommand cmd = new SqlCommand("SELECT  NoALastName, NoAFirstName, NoAMiddleName FROM CustomerCreditReport WHERE ApplicantUsername = '" + uname + "'", cs);
SqlDataReader reader = cmd.ExecuteReader();

while (reader.Read())
{
    txtLname.Text = reader["NoALastName"].ToString();
    txtFname.Text = reader["NoAFirstName"].ToString();
    txtMname.Text = reader["NoAMiddleName"].ToString();
}
cs.Close();
reader.Close();

现在，这是我的保存/更新代码。（这是在Save_Click下）

SqlDataAdapter da = new SqlDataAdapter();
da.UpdateCommand = new SqlCommand("UPDATE CustomerCreditReport SET NoALastName = @NoALastName, NoAFirstName = @NoAFirstName, NoAMiddleName = @NoAMiddleName WHERE ApplicantUsername = '" + txtUsername.Text + "'", cs);
da.UpdateCommand.Parameters.Add("@NoALastName", SqlDbType.VarChar).Value = txtLname.Text;
da.UpdateCommand.Parameters.Add("@NoAFirstName", SqlDbType.VarChar).Value = txtFname.Text;
da.UpdateCommand.Parameters.Add("@NoAMiddleName", SqlDbType.VarChar).Value = txtMname.Text;
cs.Open();
da.UpdateCommand.ExecuteNonQuery();
cs.Close();

我想知道我是否忽视了某些事情。请帮忙。谢谢。

Answer 1

在页面加载中

请确保将代码放在if（！Page.IsPostBack）之后像这样

 if (!Page.IsPostBack)
 {
  string uname = Session["ApplicantUsername1"].ToString();
        txtUsername.Text = uname;

        cs.Open();
        SqlCommand cmd = new SqlCommand("SELECT  NoALastName, NoAFirstName, NoAMiddleName FROM CustomerCreditReport WHERE   ApplicantUsername = '" + uname + "'", cs);
SqlDataReader reader = cmd.ExecuteReader();

        while (reader.Read())
        {
            txtLname.Text = reader["NoALastName"].ToString();
            txtFname.Text = reader["NoAFirstName"].ToString();
            txtMname.Text = reader["NoAMiddleName"].ToString();
        }
        cs.Close();
        reader.Close();
 }

ASP.NET：无法更新从数据库读取的值

1 个答案: