Question

我已经在2个表中创建了DatagridviewComboBoxColumns（在本例中为“ moduly”和“ zlecenia”表），并从“ projekty”表中获取了插入值。但是，当我单击“更新”按钮时，它没有保存在mysql数据库中（在projekty表中仅保存ID）。所以我不知道如何保存在数据库中（也许我应该添加一列）。有一个问题：

1. 1. 更新之前

我插入新的单元格值

更新信息后

有我的代码：New Tables.cs

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 MySql.Data.MySqlClient;
using System.Collections;

namespace KontrolaBazaDanych
{
    public partial class New_Tables : Form
    {
        public New_Tables()
        {
            InitializeComponent();
        }
        MySqlConnection connection;
        MySqlDataAdapter adapter, adapter2, adapter3, adapter4;
        DataSet ds, ds2, ds3, ds4;
        DataTable dt, dt1;
        public void New_Tables_Load(object sender, EventArgs e)
        {
            try
            {
                connection = new MySqlConnection("datasource=localhost;port=3306;username=root;password=");
                adapter2 = new MySqlDataAdapter("SELECT moduly.ID_MODULU, moduly.NAZWA, projekty.NAZWA_PROJEKTU FROM projekt1.moduly INNER JOIN projekt1.projekty ON projekty.ID = moduly.ID_PROJEKTU;", connection);
                adapter3 = new MySqlDataAdapter("SELECT zlecenia.ID_ZLECENIA, zlecenia.OPIS_ZLECENIA, zlecenia.NUMER_ZLECENIA, projekty.NAZWA_PROJEKTU FROM projekt1.zlecenia INNER JOIN projekt1.projekty ON projekty.ID = zlecenia.ID_PROJEKTU", connection);
                adapter4 = new MySqlDataAdapter("SELECT ID, TRIM(NAZWA_PROJEKTU) AS 'NAZWA PROJEKTU' FROM projekt1.projekty", connection);
                connection.Open();

                ds2 = new DataSet();
                adapter2.Fill(ds2, "moduly");
                dataGridView2.DataSource = ds.Tables["moduly"];

                ds3 = new DataSet();
                adapter3.Fill(ds3, "zlecenia");
                dataGridView3.DataSource = ds3.Tables["zlecenia"]; 

                ds4 = new DataSet();
                adapter4.Fill(ds4, "projekty");
                dataGridView4.DataSource = ds4.Tables["projekty"];

                dataGridView2.DataSource = loaddata();
                fillcombo();
                dataGridView3.DataSource = loaddata2();
                fillcombo2();
                dataGridView2.Columns[0].Visible = false;
                dataGridView3.Columns[0].Visible = false;
                dataGridView4.Columns[0].Visible = false;

                connection.Close();

            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }

        private void button1_Click(object sender, EventArgs e)
        {
            this.Close();
        }

        private void button2_Click(object sender, EventArgs e)
        {
            try
            {
                MySqlCommandBuilder cmbl2 = new MySqlCommandBuilder(adapter2);
                adapter2.Update(ds2, "moduly");
                MySqlCommandBuilder cmbl3 = new MySqlCommandBuilder(adapter3);
                adapter3.Update(ds3, "zlecenia");
                MySqlCommandBuilder cmbl4 = new MySqlCommandBuilder(adapter4);
                adapter4.Update(ds4, "projekty");
                MessageBox.Show("Informacja została zauktualizowana", "Aktualizacja", MessageBoxButtons.OK, MessageBoxIcon.Information);
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }

        }

        private void dataGridView2_RowEnter(object sender, DataGridViewCellEventArgs e)
        {
            dataGridView2.Rows[e.RowIndex].Cells[0].Value = e.RowIndex + 1;
        }

        private void dataGridView2_CurrentCellDirtyStateChanged(object sender, EventArgs e)
        {
            dataGridView2.CommitEdit(DataGridViewDataErrorContexts.Commit);
        }

        private void dataGridView3_RowEnter(object sender, DataGridViewCellEventArgs e)
        {
            dataGridView3.Rows[e.RowIndex].Cells[0].Value = e.RowIndex + 1;
        }
        private void dataGridView3_CurrentCellDirtyStateChanged(object sender, EventArgs e)
        {
            dataGridView3.CommitEdit(DataGridViewDataErrorContexts.Commit);
        }
        private void dataGridView4_RowEnter(object sender, DataGridViewCellEventArgs e)
        {
            dataGridView4.Rows[e.RowIndex].Cells[0].Value = e.RowIndex + 1;
        }
        private void dataGridView4_CurrentCellDirtyStateChanged(object sender, EventArgs e)
        {
            dataGridView4.CommitEdit(DataGridViewDataErrorContexts.Commit);
        }


        private DataTable loaddata()
        {
            MySqlDataAdapter adapter = new MySqlDataAdapter();
            MySqlCommand cmd;
            DataSet ds2 = new DataSet();

            string sql = "SELECT * FROM projekt1.moduly";

            cmd = new MySqlCommand(sql, connection);

            adapter.SelectCommand = cmd;
            adapter.Fill(ds2);

            dt = ds2.Tables[0];

            return dt;
        }
        private void fillcombo()
        {
            DataGridViewComboBoxColumn combo = new DataGridViewComboBoxColumn();
            combo.HeaderText = "NAZWA PROJEKTU";
            combo.Name = "combo";

            MySqlDataAdapter adapter = new MySqlDataAdapter();
            MySqlCommand cmd;
            DataSet ds2 = new DataSet();

            string sql = "SELECT * FROM projekt1.projekty";

            cmd = new MySqlCommand(sql, connection);

            adapter.SelectCommand = cmd;
            adapter.Fill(ds2);

            dt = ds2.Tables[0];

            ArrayList row = new ArrayList();

            Projekty_advanced.lista_projekty.Clear();
            foreach (DataRow dr in dt.Rows)
            {
                Projekty p = new Projekty();

                p.ID = (int)dr.ItemArray[0];
                p.NAZWA_PROJEKTU = (string)dr.ItemArray[1];

                Projekty_advanced.lista_projekty.Add(p);
            }

            combo.DataSource = Projekty_advanced.lista_projekty;
            combo.DisplayMember = "NAZWA_PROJEKTU";

            dataGridView2.Columns.Add(combo);
        }
        private DataTable loaddata2()
        {
            MySqlDataAdapter adapter = new MySqlDataAdapter();
            MySqlCommand cmd;
            DataSet ds3 = new DataSet();

            string sql = "SELECT * FROM projekt1.zlecenia";

            cmd = new MySqlCommand(sql, connection);

            adapter.SelectCommand = cmd;
            adapter.Fill(ds3);

            dt1 = ds3.Tables[0];

            return dt1;
        }

        private void fillcombo2()
        {
            DataGridViewComboBoxColumn combo2 = new DataGridViewComboBoxColumn();
            combo2.HeaderText = "NAZWA PROJEKTU";
            combo2.Name = "combo";

            MySqlDataAdapter adapter = new MySqlDataAdapter();
            MySqlCommand cmd;
            DataSet ds3 = new DataSet();

            string sql = "SELECT * FROM projekt1.projekty";

            cmd = new MySqlCommand(sql, connection);

            adapter.SelectCommand = cmd;
            adapter.Fill(ds3);

            dt1 = ds3.Tables[0];

            ArrayList row = new ArrayList();

            Projekty_advanced.lista_projekty.Clear();
            foreach (DataRow dr in dt.Rows)
            {
                Projekty p = new Projekty();

                p.ID = (int)dr.ItemArray[0];
                p.NAZWA_PROJEKTU = (string)dr.ItemArray[1];

                Projekty_advanced.lista_projekty.Add(p);
            }

            combo2.DataSource = Projekty_advanced.lista_projekty;
            combo2.DisplayMember = "NAZWA_PROJEKTU";

            dataGridView3.Columns.Add(combo2);
        }
    }
}

Answer 1

怎么样？

private void btnUpdate_Click(object sender, EventArgs e)
{

    using (SqlConnection con = new SqlConnection("Server=your_server_name;Database=your_db_name;Trusted_Connection=True;"))
    {

        using (SqlCommand cmd = new SqlCommand("SELECT * FROM Courses", con))
        {
            using (SqlDataAdapter da = new SqlDataAdapter(cmd))
            {
                {
                    SqlCommandBuilder sqlcmd = new SqlCommandBuilder(da);
                    DataSet ds = new System.Data.DataSet(); // remove this line
                    da.Update(this.ds, "Courses");
                }
            }
        }
    }
}

从datagridview将所有单元更新到数据库

1 个答案: