Tutorial CRUD C# Sederhana dengan MySql – Studi Kasus Pendataan Nilai Siswa

public MySqlCommand cmd;
public MySqlDataReader dr;
public String id;

private void Tampil()
{
    try
    {

Koneksi.conn.Open(); 
MySqlDataAdapter da = new MySqlDataAdapter("SELECT * FROM `guru`", Koneksi.conn);
DataSet ds = new DataSet();
da.Fill(ds);

dgsiswa.DataSource = ds.Tables[0];
Koneksi.conn.Close();
    }
    catch (Exception)
    {

MessageBox.Show("Duh!!, Ada Error Nih");
    }
}

private void Guru_Load(object sender, EventArgs e)
 {
     Tampil();
     btDelete.Enabled = false;
     btUpdate.Enabled = false;
     btCancel.Enabled = false;
 }

private void Clear()
{
    txtnama.Text = "";
    txtnip.Text = "";
    
    btDelete.Enabled = false;
    btUpdate.Enabled = false;
    btCancel.Enabled = false;
    btInsert.Enabled = true;
}

try
    {
Koneksi.conn.Open();
String Queri = "INSERT INTO guru (`nama`, `nip`) VALUES ('" + txtnama.Text + "', '" + txtnip.Text + "')";
cmd = new MySqlCommand(Queri, Koneksi.conn);
cmd.ExecuteNonQuery();
MessageBox.Show("Berhasil Simpan Data Guru");
Koneksi.conn.Close();

Tampil();
Clear();
    }
    catch (Exception)
    {

MessageBox.Show("Tambah Data Gagal");
    }

btDelete.Enabled = true;
btUpdate.Enabled = true;
btCancel.Enabled = true;
btInsert.Enabled = false;

int baris = dgsiswa.CurrentCell.RowIndex;
id = dgsiswa.Rows[baris].Cells[0].Value.ToString();
txtnama.Text = dgsiswa.Rows[baris].Cells[1].Value.ToString();
txtnip.Text = dgsiswa.Rows[baris].Cells[2].Value.ToString();

try
{
    Koneksi.conn.Open();
    String Queri = "UPDATE guru SET `nama`='" + txtnama.Text + "', `nip`='" + txtnip.Text + "' WHERE  `id`='" + id + "'";
    cmd = new MySqlCommand(Queri, Koneksi.conn);
    cmd.ExecuteNonQuery();
    MessageBox.Show("Berhasil Update Data Guru");
    Koneksi.conn.Close();

    Tampil();
    Clear();
}
catch (Exception)
{

    MessageBox.Show("Update Gagal");
}

try
{
    Koneksi.conn.Open();
    cmd = new MySqlCommand("DELETE FROM guru WHERE  `id`= '" + id + "'", Koneksi.conn);
    cmd.ExecuteNonQuery();
    MessageBox.Show("Berhasil Hapus Data Guru");
    Koneksi.conn.Close();

    Tampil();
    Clear();
}
catch (Exception)
{

    MessageBox.Show("Hapus Data Gagal");
}

 Clear();

try
{

    Koneksi.conn.Open();
    MySqlDataAdapter da = new MySqlDataAdapter("SELECT * FROM `guru` where nama LIKE '%" + txtcari.Text + "%'", Koneksi.conn);
    DataSet ds = new DataSet();

    da.Fill(ds);
    dgsiswa.DataSource = ds.Tables[0];
    Koneksi.conn.Close();
}
catch (Exception)
{

    MessageBox.Show("Duh!!, Ada Error Nih");
}