Add to kendoMultiSelect - kendo-ui

Question

With the new kendo multiselect how would I add options to the list and make them selected?
For instance if I have a dropdown containing: 1,2,3 and I wanted to add 4 and 5 how do I do that? Do I have to destroy the multiselect, add the options and then reinit the multiselect?

Answer 1

Given the following multiselect definition:
var data =
[
{ text: "Africa", value: "1" },
{ text: "Europe", value: "2" },
{ text: "Asia", value: "3" },
{ text: "North America", value: "4" },
{ text: "South America", value: "5" },
{ text: "Antarctica", value: "6" },
{ text: "Australia", value: "7" }
];
var multi = $("#select").kendoMultiSelect({
dataTextField: "text",
dataValueField: "value",
dataSource: data
}).data("kendoMultiSelect");
You can use:
var values = multi.value();
For getting the list of values.
And for setting the value to South America (element with value 5) and "Asia" (element with value 3) use:
multi.value(["5", "3"])
If you want to add values to whatever it has then you need a little trick:
var multi = $("#select").kendoMultiSelect({
dataTextField: "text",
dataValueField: "value",
dataSource: data,
value: ["1", "2", "3"]
}).data("kendoMultiSelect");
// Adding value 4 and 5 to current content
var values = multi.value().slice();
$.merge(values, ["4", "5"]);
multi.value(values);
Warning: If values 4 and 5 were already selected you will end up having them duplicated.

Answer 2

Just want to add some information about how to actually add new values to the multi-select.
As OnaBai points out, the code to add an item to the multi-select is
$("#SDropDown").data("kendoMultiSelect").dataSource.add({ Text: x, Value: y });
given the .cshtml
#(Html.Kendo()
.MultiSelect()
.Name("SDropDown")
.AutoBind(true)
.Placeholder("Select s...")
.DataTextField("Text")
.DataValueField("Value")
)
In order to add an item as entered in the multi-select hook the change event for the text input. Since this isn't uniquely identified, I use XPath to get the <input> element. This is hooked in document.ready (in .cshtml, so escape #):
$(document).ready(function () {
var node = document.evaluate('//select[##id="SDropDown"]/../div[contains(##class,"k-multiselect")]/input', document, null, XPathResult.FIRST_ORDERED_NODE_TYPE, null).singleNodeValue;
if (node)
{
node.onkeypress = SChanged;
}
}
function SChanged(e)
{
// only append on enter
if (kendo.keys.ENTER == e.keyCode)
{
// updates multi-select data source
AddToOrganizations(this.value);
var multi = $("#SDropDown").data("kendoMultiSelect");
multi.dataSource.filter({}); //clear applied filter before setting value
// keep all currently selected items and append the user entered text
// (does not check for duplicates)
// Also, the new values can only be selected after the data source has
// been updated.
var values = multi.value().slice();
$.merge(values, [this.value]);
multi.value(values);
}
}