Editable dropdown list box

Editable dropdown list box

An "editable drop-down list" or a combo-box per se is not supported by any browser, at least not by IE and Netscape. So having this type of control is not possible. However, what could be done is to use a textbox along with a drop-down list and add the contents of the textbox to the drop-down when the TextChanged event of the textbox fires. Here's how: Technique 1: Using client-side code (note that asp.net controls can also be used here) <script> function addToCombo(val, obj) { if(val.length > 0) { obj.options.add(new Option(val)); } } </script> <input type=text name="txtCombo" onchange="addToCombo(this.value, this.form.selCombo)"><br> <select name="selCombo"></select> Technique 2: Using code-behind (C#) <asp:TextBox id="txtCombo" runat="Server"/><br> <asp:dropdownlist id="selCombo" runat="Server"/> code behind: private void txtCombo_TextChanged(...) { if(txtCombo.Text.Trim().Length > 0) { selCombo.Items.Add(new ListItem(txtCombo.Text)); } }