aksenov_exam_main/WindowsFormsApp2/Admin.cs

using MySql.Data.MySqlClient;
using System;
using System.Data;
using System.Windows.Forms;

namespace WindowsFormsApp2
{
    public partial class Admin : Form
    {
        string connectionString = "Server=85.239.57.125; Database=Gavrilov_Aksenov_exam; Uid=ISP41_Gavrilov; Pwd=ISP41_Gavrilov;";

        public Admin()
        {
            InitializeComponent();
            LoadOrders();
            buttonAdd.Click += ButtonAdd_Click;
            buttonEdit.Click += ButtonEdit_Click;
            buttonDelete.Click += ButtonDelete_Click;
            textBoxSearch.TextChanged += TextBoxSearch_TextChanged;
            comboBoxFilter.SelectedIndexChanged += ComboBoxFilter_SelectedIndexChanged;
            comboBoxSort.SelectedIndexChanged += ComboBoxSort_SelectedIndexChanged;
        }

        void LoadOrders()
        {
            using (MySqlConnection conn = new MySqlConnection(connectionString))
            {
                conn.Open();
                string query = "SELECT o.id, o.order_number, u.full_name, s.name as status, o.pickup_address, o.order_date, o.delivery_date FROM orders o JOIN users u ON o.user_id = u.id JOIN status s ON o.status = s.idstatus";
                MySqlDataAdapter adapter = new MySqlDataAdapter(query, conn);
                DataTable dt = new DataTable();
                adapter.Fill(dt);
                dataGridView1.DataSource = dt;
            }
        }

        void ButtonAdd_Click(object sender, EventArgs e)
        {
            OrderEditForm form = new OrderEditForm(connectionString, null);
            if (form.ShowDialog() == DialogResult.OK)
            {
                LoadOrders();
            }
        }

        void ButtonEdit_Click(object sender, EventArgs e)
        {
            if (dataGridView1.SelectedRows.Count > 0)
            {
                int id = Convert.ToInt32(dataGridView1.SelectedRows[0].Cells["id"].Value);
                OrderEditForm form = new OrderEditForm(connectionString, id);
                if (form.ShowDialog() == DialogResult.OK)
                {
                    LoadOrders();
                }
            }
        }

        void ButtonDelete_Click(object sender, EventArgs e)
        {
            if (dataGridView1.SelectedRows.Count > 0)
            {
                int id = Convert.ToInt32(dataGridView1.SelectedRows[0].Cells["id"].Value);
                using (MySqlConnection conn = new MySqlConnection(connectionString))
                {
                    conn.Open();
                    string query = "DELETE FROM orders WHERE id = @id";
                    MySqlCommand cmd = new MySqlCommand(query, conn);
                    cmd.Parameters.AddWithValue("@id", id);
                    cmd.ExecuteNonQuery();
                }
                LoadOrders();
            }
        }

        void TextBoxSearch_TextChanged(object sender, EventArgs e)
        {
            FilterAndSort();
        }

        void ComboBoxFilter_SelectedIndexChanged(object sender, EventArgs e)
        {
            FilterAndSort();
        }

        void ComboBoxSort_SelectedIndexChanged(object sender, EventArgs e)
        {
            FilterAndSort();
        }

        void FilterAndSort()
        {
            string search = textBoxSearch.Text;
            string filter = comboBoxFilter.Text;
            string sort = comboBoxSort.Text;
            string query = "SELECT o.id, o.order_number, u.full_name, s.name as status, o.pickup_address, o.order_date, o.delivery_date FROM orders o JOIN users u ON o.user_id = u.id JOIN status s ON o.status = s.idstatus WHERE 1=1";
            if (!string.IsNullOrEmpty(search))
            {
                if (filter == "По имени")
                {
                    query += " AND u.full_name LIKE '%" + search + "%'";
                }
                else if (filter == "По категории")
                {
                    query += " AND o.order_number LIKE '%" + search + "%'";
                }
                else
                {
                    query += " AND (o.order_number LIKE '%" + search + "%' OR u.full_name LIKE '%" + search + "%')";
                }
            }
            if (sort == "По имени А-Я")
            {
                query += " ORDER BY u.full_name ASC";
            }
            else if (sort == "По имени Я-А")
            {
                query += " ORDER BY u.full_name DESC";
            }
            else if (sort == "По цене возр.")
            {
                query += " ORDER BY o.order_date ASC";
            }
            else if (sort == "По цене убыв.")
            {
                query += " ORDER BY o.order_date DESC";
            }
            using (MySqlConnection conn = new MySqlConnection(connectionString))
            {
                conn.Open();
                MySqlDataAdapter adapter = new MySqlDataAdapter(query, conn);
                DataTable dt = new DataTable();
                adapter.Fill(dt);
                dataGridView1.DataSource = dt;
            }
        }

        private void button1_Click(object sender, EventArgs e)
        {
            Author form1 = new Author();
            form1.Show();
            this.Hide();
        }
    }
}