使用访问数据库将用户登录数据从Form1传递到Form2 ListView

Question

I have created a program that needs to pass the employee number login data (Log_in) to the 2nd form (form1). I already created the database that consist of 3 tables: Employee_Information, SN_Incoming, and Duplicate. I want the employee number found in the Employee Information move over to the SN_Incoming table. That data will then be displayed in a listview.

Login Form Code:

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Data.OleDb;

namespace Serial_Number_Checker
{
public partial class Log_In : Form
{

    public Log_In()
    {
        InitializeComponent();
    }

    private void button1_Click(object sender, EventArgs e)
    {
        if (string.IsNullOrEmpty(textBox1.Text))
        {
            MessageBox.Show("Please enter your employee #!", "Message", MessageBoxButtons.OK, MessageBoxIcon.Warning);
            textBox1.Focus();
            return;
        }
        try
        {
            Duplicate_Serial_Number_CheckerDataSetTableAdapters.Employee_InformationTableAdapter Employee_Number = new Duplicate_Serial_Number_CheckerDataSetTableAdapters.Employee_InformationTableAdapter();
            Duplicate_Serial_Number_CheckerDataSet.Employee_InformationDataTable dt = Employee_Number.GetDataByEmployee_Number(textBox1.Text);
            if (dt.Rows.Count > 0)
            {
                MessageBox.Show("You have been successfully logged in.", "Message", MessageBoxButtons.OK, MessageBoxIcon.Information); // Process your login here
                this.Hide();
                Form1 form1 = new Form1();
                if (form1.ShowDialog() != DialogResult.OK)
                Application.Exit();
            }
            else
            {
                MessageBox.Show("Your Employee # is not registered. Please contact your Supervisor to be registered.", "Message", MessageBoxButtons.OK, MessageBoxIcon.Information);
            }
        }
        catch (Exception ex)
        {
            MessageBox.Show(ex.Message, "Message", MessageBoxButtons.OK, MessageBoxIcon.Error);

        }
    }

    private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
    {
        if (e.KeyChar == (char)13)
            button1.PerformClick();
    }
}

}

Form1 Code:

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Configuration;
using System.Data.OleDb;

namespace Serial_Number_Checker
{
public partial class Form1 : Form
{
    static string conString= "Provider=Microsoft.ACE.OLEDB.12.0;DataSource=";
    OleDbConnection con = new OleDbConnection(conString);
    OleDbCommand cmd;
    OleDbDataAdapter adapter;
    DataTable dt = new DataTable();

    public Form1()
    {
        InitializeComponent();

        listView1.SelectedIndexChanged += new EventHandler        (listView1_SelectedIndexChanged); // Adding columns to listView1

        // list view properities
        listView1.View = View.Details;
        listView1.FullRowSelect = true;

        // Add Columns
        listView1.Columns.Add("Employee #", 150);
        listView1.Columns.Add("Serial Number", 150);
        listView1.Columns.Add("Date/Time", 150);            
    }







    // Add Row
    private void InsertSerialNumber(string sn)
    {
        using (OleDbCommand odc = new OleDbCommand("INSERT INTO SN_Incoming (SN) VALUES(@SN)", con))
        {
            odc.Parameters.AddWithValue("@SN", sn);
            try
            {
                con.Open();
                odc.ExecuteNonQuery();
            }
            catch (Exception e) { MessageBox.Show(e.Message);
            }
            finally { con.Close();
            }
        }
    }





    // Add To ListView1
    private void populate(String employeeid, String sn, String timestamp)
    {
        // Row
        String[] row = { employeeid, sn, timestamp };

        ListViewItem item = new ListViewItem(row);

        listView1.Items.Add(item);
    }





    private void clearTxts()
    {
        textBox1.Text = "";
    }



    // Retrieve Check In
    private void LoadSerialNumbers() {
    listView1.Items.Clear();
    DataTable dt = new DataTable();
    using (OleDbCommand odc = new OleDbCommand("SELECT * FROM SN_Incoming", con)) {
    try {
        con.Open();
        using (OleDbDataAdapter oda = new OleDbDataAdapter(odc))
            oda.Fill(dt);
    } catch (Exception e) { MessageBox.Show(e.Message); } finally { con.Close(); }
}

    List<ListViewItem> items = new List<ListViewItem>();
    foreach (DataRow row in dt.Rows) {
    ListViewItem lvi = items.SingleOrDefault(s => s.Tag == row[1].ToString());
    if (lvi != null)
        continue;

    lvi = new ListViewItem(new string[] { row[0].ToString(), row[1].ToString(), row[2].ToString() });
    lvi.Tag = row[1].ToString();
    items.Add(lvi);
}

listView1.Items.AddRange(items.ToArray());

}

    private void listView1_SelectedIndexChanged(object sender, EventArgs e)
    {


    }
    private void textBox1_TextChanged(object sender, EventArgs e)
    {

    }



    private void button1_Click(object sender, EventArgs e)
    {
        {
            foreach (ListViewItem lvi in listView1.SelectedItems)
                listView1.Items.Remove(lvi);

            if (string.IsNullOrWhiteSpace(textBox1.Text))
                MessageBox.Show("Please enter a serial number!", "Input");
            else
                InsertSerialNumber(textBox1.Text);

            textBox1.Text = string.Empty;
            textBox1.Focus();
            textBox1.SelectionStart = textBox1.Text.Length == 0 ? 0 : textBox1.Text.Length - 1;
            textBox1.SelectionLength = 0;

            LoadSerialNumbers();
        }
    }

    private void button2_Click(object sender, EventArgs e)
    {
        Application.Exit();
    }

    private void listView1_SelectedIndexChanged_1(object sender, EventArgs e)
    {

    }

    private void button3_Click(object sender, EventArgs e)
    {

    }

    private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
    {


    }


    // If enter is pressed down during input, it will automatically submit
    private void textBox1_KeyDown(object sender, KeyEventArgs e)
    {
        if (e.KeyCode == Keys.Enter)
        {
            button1_Click(this, new EventArgs());
        }
    }
}

}

I have already set my primary key to Employee_Number. I need to learn how to pass that information to the next table. So I can retrieve and put in my listview. Your help is greatly appreciated. Thanks

Answer 1

Just add a parameter to the constructor of Form1 :

public Form1(string id)
{
    InitializeComponent();
    //Do whatever you like with the passed-in id:
    MessageBox.Show($"you passed me Id {id}");
}         

To Use:

Form1 form1 = new Form1(TextBox1.Text);
if (form1.ShowDialog() != DialogResult.OK)
    Application.Exit();

Though Generally, I'd advise moving all the DB stuff and 'Who's currently logged in' code to separate repository/service classes which are commonly available everywhere.