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POVisual c# relatively dynamic comboboxes
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copied!<p>I have two related comboboxes, combobox1 populate the items of combobox2. In combobox1 <code>selectIndexChanged</code> event I have this code but i have error <code>Unknown column 'System.Data.DataRowView' in 'where clause'</code>. <br><br></p> <p>I tried to put this code in the <code>SelectionChangeCommitted</code> at first selection, it populate the right items, but my second selection i have error in <code>comboBox2.Items.Clear();</code> states <code>Items collection cannot be modified when the DataSource property is set.</code> :( what to do.?</p> <pre><code>private void comboBox1_SelectedIndexChanged(object sender, EventArgs e) { string sql; if (comboBox1.SelectedIndex >= 0) { comboBox2.Items.Clear(); MySqlConnection conn = new MySqlConnection(sqlString); MySqlDataAdapter adapter = new MySqlDataAdapter(); sql = "SELECT brgyname,idbrgy from barangay where idmun=" + comboBox1.SelectedValue; adapter.SelectCommand = new MySqlCommand(sql, conn); DataTable cbBrgy = new DataTable(); adapter.Fill(cbBrgy); comboBox2.DataSource = cbBrgy; comboBox2.DisplayMember = "brgyname"; comboBox2.ValueMember = "idbrgy"; } } </code></pre> <p>Here's how i populate combobox1</p> <pre><code> private void cbMun() { MySqlConnection conn = new MySqlConnection(sqlString); MySqlDataAdapter adapter = new MySqlDataAdapter(); adapter.SelectCommand = new MySqlCommand("SELECT munname,idmun from municipality", conn); DataTable cbMun = new DataTable(); adapter.Fill(cbMun); comboBox1.DataSource = cbMun; comboBox1.DisplayMember = "munname"; comboBox1.ValueMember = "idmun"; } </code></pre>

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