单击某些按钮时弹出拒绝访问消息，具体取决于登录的用户

Question

在登录形式中，当我以DOCTOR表中存在的杰克登录时，它将转到page_two。如果单击护士按钮 1 或护士按钮 2，我想弹出拒绝访问消息，因为杰克不是护士而是医生。然后相反，如果我以 NURSE 表中存在的 Mary 身份登录，它将转到page_two。我想在单击医生按钮 1 或医生按钮 2 时弹出拒绝访问消息，因为玛丽不是医生而是护士。

Page_two的按钮名称是 btnDoctor1、btnDoctor2、btnNurse1 和 btnNurse2

。

**//login Form codes**

    using System;
    using System.Collections.Generic;
    using System.ComponentModel;
    using System.Data;
    using System.Drawing;
    using System.Linq;
    using System.Text;
    using System.Windows.Forms;
    using System.Data.SqlClient;
    using System.Configuration;
    namespace GRP_02_03_SACP
    {
        public partial class page_one : Form
        {
            public page_one()
            {
                InitializeComponent();
            }

            private void page_one_Load(object sender, EventArgs e)
            {
            }
            private void btnLogin_Click(object sender, EventArgs e)
            {
                //retrieve connection information info from App.config
                string strConnectionString = ConfigurationManager.ConnectionStrings["sacpConnection"].ConnectionString;
                //STEP 1: Create connection
                SqlConnection myConnect = new SqlConnection(strConnectionString);
                //STEP 2: Create command
                string strCommandtext = "SELECT dUsername, dPassword from DOCTOR";
                // Add a WHERE Clause to SQL statement
                strCommandtext += "   WHERE dUsername=@dname AND dPassword=@dpwd;";
                strCommandtext += "SELECT nUsername, nPassword from NURSE WHERE nUsername=@nname AND nPassword=@npwd;";
                SqlCommand cmd = new SqlCommand(strCommandtext, myConnect);
                cmd.Parameters.AddWithValue("@dname", textUsername.Text);
                cmd.Parameters.AddWithValue("@dpwd", txtPassword.Text);
                cmd.Parameters.AddWithValue("@nname", textUsername.Text);
                cmd.Parameters.AddWithValue("@npwd", txtPassword.Text);

                try
                {
                    // STEP 3: open connection and retrieve data by calling ExecuteReader
                    myConnect.Open();
                    // STEP 4: Access Data
                    SqlDataReader reader = cmd.ExecuteReader();

                    while (reader.Read()) //For Doctor
                    {
                        if (MessageBox.Show("Login Successful") == DialogResult.OK)
                        {
                            page_two form = new page_two();
                            form.Show();
                            return;
                        }                                     
                    } 
                    reader.NextResult();
                    while (reader.Read()) //For Nurse
                    {
                        if (MessageBox.Show("Login Successful") == DialogResult.OK)
                        {
                            page_two form = new page_two();
                            form.Show();
                            return;
                        }
                    }
                    //STEP 5: close connection
                    reader.Close();
                    MessageBox.Show("Invalid username or password");
                }
                catch (SqlException ex)
                {
                }
                finally
                {
                    //STEP 5: close connection
                    myConnect.Close();
                }
            }      
        }
    }

代码 Page_two

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
namespace GRP_02_03_SACP
{
    public partial class page_two : Form
    {
        public page_two()
        {
            InitializeComponent();
        }
        private void btnDoctor1_Click(object sender, EventArgs e)
        {
        }
        private void btnDoctor2_Click(object sender, EventArgs e)
        {
        }
        private void btnNurse1_Click(object sender, EventArgs e)
        {
        }
        private void btnNurse2_Click(object sender, EventArgs e)
        {
        }
    }
}

Answer 1

将此添加到您的代码中：

 public Int JobPosition;

在这里，您将定义每个位置。

将btnLogin_Click上的代码更改为：

  private void btnLogin_Click(object sender, EventArgs e)
        {
            //retrieve connection information info from App.config
            string strConnectionString = ConfigurationManager.ConnectionStrings["sacpConnection"].ConnectionString;
            //STEP 1: Create connection
            SqlConnection myConnect = new SqlConnection(strConnectionString);
            //STEP 2: Create command
            string strCommandtext = "SELECT dUsername, dPassword from DOCTOR";
            // Add a WHERE Clause to SQL statement
            strCommandtext += "   WHERE dUsername=@dname AND dPassword=@dpwd;";
            strCommandtext += "SELECT nUsername, nPassword from NURSE WHERE nUsername=@nname AND nPassword=@npwd;";
            SqlCommand cmd = new SqlCommand(strCommandtext, myConnect);
            cmd.Parameters.AddWithValue("@dname", textUsername.Text);
            cmd.Parameters.AddWithValue("@dpwd", txtPassword.Text);
            cmd.Parameters.AddWithValue("@nname", textUsername.Text);
            cmd.Parameters.AddWithValue("@npwd", txtPassword.Text);

            try
            {
                // STEP 3: open connection and retrieve data by calling ExecuteReader
                myConnect.Open();
                // STEP 4: Access Data
                SqlDataReader reader = cmd.ExecuteReader();

                while (reader.Read()) //For Doctor
                {
                    if (MessageBox.Show("Login Successful") == DialogResult.OK)
                    {
                        JobPosition = 1; //Doctor
                        page_two form = new page_two(JobPosition);
                        form.Show();
                        return;
                    }                                     
                } 
                reader.NextResult();
                while (reader.Read()) //For Nurse
                {
                    if (MessageBox.Show("Login Successful") == DialogResult.OK)
                    {
                        JobPosition = 2; //Nurse
                        page_two form = new page_two(JobPosition);
                        form.Show();
                        return;
                    }
                }
                //STEP 5: close connection
                reader.Close();
                MessageBox.Show("Invalid username or password");
            }
            catch (SqlException ex)
            {
            }
            finally
            {
                //STEP 5: close connection
                myConnect.Close();
            }
        }    

在Page_two代码上：

 using System;
 using System.Collections.Generic;
 using System.ComponentModel;
 using System.Data;
 using System.Drawing;
 using System.Linq;
 using System.Text;
 using System.Windows.Forms;
namespace GRP_02_03_SACP
{
public partial class page_two : Form
{
    private Int JopPosition;
    public page_two()
    {
        InitializeComponent();
    }
    public page_two(Int _Position)
    {
        InitializeComponent();
        JopPosition = _Position;
    }
    private void btnDoctor1_Click(object sender, EventArgs e)
    {
    }
    private void btnDoctor2_Click(object sender, EventArgs e)
    {
    }
    private void btnNurse1_Click(object sender, EventArgs e)
    {
        if (JopPosition == 1)
        {
           MessageBox.Show("access denied");
        }
    }
    private void btnNurse2_Click(object sender, EventArgs e)
    {
    }
}

}