Implementing an editable DropDownList in ASP.NET
Question
What's the most elegant way of implementing a DropDownList in ASP.NET that is editable without using 3rd party components.
As a last resort I will probably try using a TextBox with an AutoCompleteExtender with an image to 'drop down' the list; or a TextBox overlapping a HTML Select with some JavaScript to fill values from the Select to the TextBox . But I'm really hoping there is a more terse and maintainable solution.
Thanks in advance.
3 answers
solution1
5 2009-10-20 02:06:39
One Control on a Page
You can follow
this simple example for an Editable DropDownlist on Code Project
that uses standard ASP.NET TextBox and DropDownList controls combined with some JavaScript.
However, the code did not work for me until I added a reference to get the ClientID values for the TextBox and DropDownList:
<script language="javascript" type="text/javascript">
function DisplayText()
{
var textboxId = '<% = txtDisplay.ClientID %>';
var comboBoxId = '<% = ddSelect.ClientID %>';
document.getElementById(textboxId).value = document.getElementById(comboBoxId).value;
document.getElementById(textboxId).focus();
}
</script>
<asp:TextBox style="width:120px;position:absolute" ID="txtDisplay" runat="server"></asp:TextBox>
<asp:DropDownList ID="ddSelect" style="width:140px" runat="server">
<asp:ListItem Value="test1" >test1</asp:ListItem>
<asp:ListItem Value="test2">test2</asp:ListItem>
</asp:DropDownList>
Finally, in the code behind just like in the original example, I added the following to page load:
protected void Page_Load(object sender, EventArgs e)
{
ddSelect.Attributes.Add("onChange", "DisplayText();");
}
Multiple Controls on a Page
I placed all of the above code in its own ASCX User Control to make it reusable across my project. However, the code as presented above only works if you require just one editable DropDownList on a given page.
If you need to support multiple custom DropDownList controls on a single page, it is necessary to set the JavaScript function name to be unique to avoid conflicts. Do this by once again using the ClientID:
in the ASCX file:
function DisplayText_<% = ClientID %>(){...}
in the code behind:
/// ...
ddSelect.Attributes.Add("onChange", "DisplayText_" + ClientID + "();");
///..
This is one way to avoid using 3rd party controls.
solution2
1 2017-03-03 09:01:28
You can try using JqueryUI Autocomplete Combobox.
It will let you type in text as well as select the item of your choice from a dropdown.
As an extra feature it lets you use the autocomplete feature to get a enhance UI experience.
I am attaching a demo which is coupled with bootstrap 3.3.4
<!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head runat="server"> <title></title> <script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/js/bootstrap.min.js"></script> <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script> <link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/css/bootstrap.min.css" rel="stylesheet" /> <link href="https://code.jquery.com/ui/1.11.4/themes/smoothness/jquery-ui.css" rel="stylesheet" /> <script src="https://code.jquery.com/jquery-1.10.2.js"></script> <script src="https://code.jquery.com/ui/1.11.4/jquery-ui.js"></script> <link href="https://jqueryui.com/resources/demos/style.css" rel="stylesheet" /> <style> .custom-combobox { position: relative; display: inline-block; } .custom-combobox-toggle { position: absolute; top: 0; bottom: 0; margin-left: -1px; padding: 0; } .custom-combobox-input { margin: 0; padding: 5px 10px; } .ui-state-default, .ui-widget-content .ui-state-default, .ui-widget-header .ui-state-default { border: 1px solid #421D1D; background: #ffffff url("images/ui-bg_glass_75_e6e6e6_1x400.png") 50% 50% repeat-x !important; font-weight: normal; color: #555555; } /* Corner radius */ .ui-corner-all, .ui-corner-top, .ui-corner-left, .ui-corner-tl { border-top-left-radius: 0px !important; } .ui-corner-all, .ui-corner-top, .ui-corner-right, .ui-corner-tr { border-top-right-radius: 0px !important; } .ui-corner-all, .ui-corner-bottom, .ui-corner-left, .ui-corner-bl { border-bottom-left-radius: 0px !important; } .ui-corner-all, .ui-corner-bottom, .ui-corner-right, .ui-corner-br { border-bottom-right-radius: 0px !important; } </style> <script> (function($) { $.widget("custom.combobox", { _create: function() { this.wrapper = $("<span>") .addClass("custom-combobox") .insertAfter(this.element); this.element.hide(); this._createAutocomplete(); this._createShowAllButton(); }, _createAutocomplete: function() { var selected = this.element.children(":selected"), value = selected.val() ? selected.text() : ""; this.input = $("<input>") .appendTo(this.wrapper) .val(value) .attr("title", "") .addClass("custom-combobox-input ui-widget ui-widget-content ui-state-default ui-corner-left") .autocomplete({ delay: 0, minLength: 0, source: $.proxy(this, "_source") }) .tooltip({ tooltipClass: "ui-state-highlight" }); this._on(this.input, { autocompleteselect: function(event, ui) { ui.item.option.selected = true; this._trigger("select", event, { item: ui.item.option }); }, autocompletechange: "_removeIfInvalid" }); }, _createShowAllButton: function() { var input = this.input, wasOpen = false; $("<a>") .attr("tabIndex", -1) .attr("title", "Show All Items") .tooltip() .appendTo(this.wrapper) .button({ icons: { primary: "ui-icon-triangle-1-s" }, text: false }) .removeClass("ui-corner-all") .addClass("custom-combobox-toggle ui-corner-right") .mousedown(function() { wasOpen = input.autocomplete("widget").is(":visible"); }) .click(function() { input.focus(); // Close if already visible if (wasOpen) { return; } // Pass empty string as value to search for, displaying all results input.autocomplete("search", ""); }); }, _source: function(request, response) { var matcher = new RegExp($.ui.autocomplete.escapeRegex(request.term), "i"); response(this.element.children("option").map(function() { var text = $(this).text(); if (this.value && (!request.term || matcher.test(text))) return { label: text, value: text, option: this }; })); }, _removeIfInvalid: function(event, ui) { // Selected an item, nothing to do if (ui.item) { return; } // Search for a match (case-insensitive) var value = this.input.val(), valueLowerCase = value.toLowerCase(), valid = false; this.element.children("option").each(function() { if ($(this).text().toLowerCase() === valueLowerCase) { this.selected = valid = true; return false; } }); // Found a match, nothing to do if (valid) { return; } // Remove invalid value this.input .val("") .attr("title", value + " didn't match any item") .tooltip("open"); this.element.val(""); this._delay(function() { this.input.tooltip("close").attr("title", ""); }, 2500); this.input.autocomplete("instance").term = ""; }, _destroy: function() { this.wrapper.remove(); this.element.show(); } }); })(jQuery); $(function() { $("#combobox").combobox(); $("#toggle").click(function() { $("#combobox").toggle(); }); }); </script> </head> <body> <form id="form1" runat="server"> <div> <div class="ui-widget"> <select id="combobox" class="form-control"> <option value="">Select your option</option> <option value="Apple">Apple</option> <option value="Banana">Banana</option> <option value="Cherry">Cherry</option> <option value="Date">Date</option> <option value="Fig">Fig</option> <option value="Grape">Grape</option> <option value="Kiwi">Kiwi</option> <option value="Mango">Mango</option> <option value="Orange">Orange</option> <option value="Pumpkin">Pumpkin</option> <option value="Strawberry">Strawberry</option> <option value="Tomato">Tomato</option> <option value="Watermelon">Watermelon</option> </select> </div> </div> </form> </body> </html>
Chrome Browser Version 43.0.2334.0 dev-m (64-bit)
Internet Explorer 11
Firefox 36.0.1
Visual Studio 2013 edition
Hope this solves your issue.
solution3
1 2011-02-10 18:38:41
The 2 solution here did the trick for me. so koodos for Ray.
Also you should look into the http://ajaxcontroltoolkit.codeplex.com/releases/view/43475 , which is the ajaxcontroltoolkit.
I don't believe the version for framework 4 comes with a comboBox component, which is here: http://www.asp.net/AJAX/AjaxControlToolkit/Samples/ComboBox/ComboBox.aspx and is very cool. Specially if you set it like this:
ajaxToolkit:ComboBox ID=ComboBox1 runat=server AutoPostBack=False
DropDownStyle=DropDown AutoCompleteMode=Suggest
CaseSensitive=False ItemInsertLocation="OrdinalText"
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