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POUpdate access db from textbox value
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copied!<p>im new in c# and asp.net world! I have a problem. In access db i have 2 table ( book, loan ) with a referential integrity constraint ( book.ID = loan.ID ).</p> <p>In my project i have some textbox and when i change a value of textbox i must update the tables.</p> <pre><code>protected void Button1_Click(object sender, EventArgs e) { cod = Request["cod"]; //Componiamo la stringa di interrogazione al database relativa alla tabella b_prestiti qry = "UPDATE b_libri SET codice='" + TextBox1.Text + "' WHERE codice='" + cod + "'"; string qry2 = "SELECT codice_libro FROM b_prestiti WHERE codice_libro='" + cod + "'"; string qry3 = "UPDATE b_prestiti SET codice_libro='"+ TextBox1.Text + "' WHERE codice_libro='" + cod + "'"; string qry4 = "UPDATE b_libri SET titolo='" + TextBox2.Text + "' WHERE codice='" + cod + "'"; string qry5 = "UPDATE b_libri SET autore='" + TextBox3.Text + "' WHERE codice='" + cod + "'"; string qry6 = "UPDATE b_libri SET editore='" + TextBox4.Text + "' WHERE codice='" + cod + "'"; //Creiamo gli oggetti di tipo OleDbConnection //passando la stringa di connessione al costruttore conn = new OleDbConnection(ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString); OleDbConnection conn2 = new OleDbConnection(ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString); OleDbConnection conn3 = new OleDbConnection(ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString); //Inizializziamo gli oggetti di tipo OleDbCommand cmd = conn.CreateCommand(); OleDbCommand cmd2 = conn2.CreateCommand(); OleDbCommand cmd3 = conn3.CreateCommand(); OleDbDataReader reader2 = null; //OleDbDataReader reader3 = null; //Apriamo la connessione conn.Open(); conn2.Open(); conn3.Open(); /* cmd2.CommandText = qry2; reader2 = cmd2.ExecuteReader();*/ if (MessageBox.Show("Sei sicuro di voler aggiornare questo libro?", "Confirmation", MessageBoxButtons.YesNo) == DialogResult.Yes) { if (!first_titolo.Equals(TextBox2.Text) || !first_autore.Equals(TextBox3.Text) || !first_editore.Equals(TextBox4.Text)) { /* while (reader2.Read()) { if (reader2["codice_libro"] != "") { if (MessageBox.Show("VINCOLI REFERENZIALI! Vuoi aggiornare comunque?", "Confirmation", MessageBoxButtons.YesNo) == DialogResult.Yes) { cmd3.CommandText = qry3; reader3 = cmd3.ExecuteReader(); reader3.Close(); MessageBox.Show("Vincolo Aggiornato!"); } else Response.Redirect("Default.aspx"); } }*/ /*cmd.CommandText = qry; reader = cmd.ExecuteReader(); reader.Close();*/ MessageBox.Show("aggiornato!"); } else MessageBox.Show("no"); /* if (first_titolo != TextBox2.Text) { cmd.CommandText = qry4; reader = cmd.ExecuteReader(); reader.Close(); MessageBox.Show("Aggiornato!"); } if (first_autore != TextBox3.Text) { cmd.CommandText = qry5; reader = cmd.ExecuteReader(); reader.Close(); MessageBox.Show("Aggiornato!"); } if (first_editore != TextBox4.Text) { cmd.CommandText = qry6; reader = cmd.ExecuteReader(); reader.Close(); MessageBox.Show("Aggiornato!"); } */ } //else Response.Redirect("Default.aspx"); // reader2.Close(); //Chiudiamo la connessione conn.Close(); conn2.Close(); conn3.Close(); } </code></pre> <p>I don't know how do it! Help me please!</p>

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