C# 我想根据用户id的会话将数据从SQL Server显示到ASP.NET文本框

我尝试了下面的编码，但什么也没发生。所有文本框均为空

protected void Page_Load(object sender, EventArgs e)
{

    SqlConnection con = new SqlConnection("Data Source=USER-PC;Initial Catalog=1GCAttendanceManagementSystem;Integrated Security=True");

    DataTable dt = new DataTable();

    con.Open();

    SqlDataReader myReader = null;

    SqlCommand myCommand = new SqlCommand("select * from Employee where EmpUsername='" + Session["id"] + "'", con);

    myReader = myCommand.ExecuteReader();

    while (myReader.Read())
    {
        txtCode.Text = (myReader["EmployeeId"].ToString());
        txtUsername.Text = (myReader["EmpUsername"].ToString());
        txtPass.Text = (myReader["EmpPassword"].ToString());
        txtEmail.Text = (myReader["EmpEmail"].ToString());
        txtFirstname.Text = (myReader["EmpFirstName"].ToString());
        txtLastname.Text = (myReader["EmpLastName"].ToString());
        txtGender.Text = (myReader["EmpGender"].ToString());
        txtContact.Text = (myReader["EmpContact"].ToString());
        txtAddress.Text = (myReader["EmpAddress"].ToString());
        txtDept.Text = (myReader["EmpDept"].ToString());
    }

    con.Close();
}

---

你能试试下面的吗

为了更好地实现，我做了如下几项更改

• 已删除SQL注入漏洞
• 连接已更改为使用
• 而（myReader.Read（））更改为if（myReader.Read（））

如果您遇到任何错误，请更新您的问题

protected void Page_Load(object sender, EventArgs e)
        {

            using (SqlConnection con = new SqlConnection("Data Source=USER-PC;Initial Catalog=1GCAttendanceManagementSystem;Integrated Security=True"))
            {

                con.Open();

                SqlDataReader myReader = null;

                var salaryParam = new SqlParameter("EmpUsername", SqlDbType.VarChar);
                salaryParam.Value = Session["id"];

                SqlCommand myCommand = new SqlCommand("select TOP 1 * from Employee where EmpUsername='@EmpUsername'", con);
                myCommand.Parameters.Add(salaryParam);

                myReader = myCommand.ExecuteReader();

                if (myReader.Read())
                {
                    txtCode.Text = (myReader["EmployeeId"].ToString());
                    txtUsername.Text = (myReader["EmpUsername"].ToString());
                    txtPass.Text = (myReader["EmpPassword"].ToString());
                    txtEmail.Text = (myReader["EmpEmail"].ToString());
                    txtFirstname.Text = (myReader["EmpFirstName"].ToString());
                    txtLastname.Text = (myReader["EmpLastName"].ToString());
                    txtGender.Text = (myReader["EmpGender"].ToString());
                    txtContact.Text = (myReader["EmpContact"].ToString());
                    txtAddress.Text = (myReader["EmpAddress"].ToString());
                    txtDept.Text = (myReader["EmpDept"].ToString());
                }

            }
        }

---

如果您的连接字符串、查询和检索字段名称正确，请在页面加载中尝试此代码…它将起作用

if (!IsPostBack)
                {
                    con.Open();
                    SqlCommand cmd = new SqlCommand("select * from Employee where EmpUsername='" + Session["id"] + "'",con);
                    SqlDataReader dr = cmd.ExecuteReader();
                    while (dr.Read())
                    {
                         txtCode.Text = (dr["EmployeeId"].ToString());
                    txtUsername.Text = (dr["EmpUsername"].ToString());
                    txtPass.Text = (dr["EmpPassword"].ToString());
                    txtEmail.Text = (dr["EmpEmail"].ToString());
                    txtFirstname.Text = (dr["EmpFirstName"].ToString());
                    txtLastname.Text = (dr["EmpLastName"].ToString());
                    txtGender.Text = (dr["EmpGender"].ToString());
                    txtContact.Text = (dr["EmpContact"].ToString());
                    txtAddress.Text = (dr["EmpAddress"].ToString());
                    txtDept.Text = (dr["EmpDept"].ToString());
                    }
                    dr.Close();
                    con.Close();
                }

---

-您不应该将SQL语句连接在一起-使用参数化查询来避免SQL注入-签出并放入调试器，然后检查是否获取值？我已经选中了，文本框仍然为空。放入断点检查会话[“id”]是否为空..如果您的表中包含具有该特定会话[“id”的数据]当然，剩下的代码会在文本框中给出结果。如果你需要进一步的帮助，请询问我。。