assign C# string of array or string[] to javascript array

I have a js code in which an array works well when its like

var availableTags = [

I then made an array string in my code behind or .cs like on class level

 public static string[] test={"animal","lovely"};

I then changed js array to this

 var availableTags =  "<%=test%>"; // also tried without quotes 

Now I m not having the results as was having with previous js array

Editing with complete code,the jquery I taken from

  using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

using System.Collections;
using System.Web.Script.Serialization;

public partial class onecol : System.Web.UI.Page
   JavaScriptSerializer serializer;

   public static string test = "['animal','lovely']";
    public static string check;

    protected void Page_Load(object sender, EventArgs e)
       serializer = new JavaScriptSerializer();
        this.detail.ToolsFile = "BasicTools.xml";
        test = returnTitle();


and the script with html is

<asp:Content ID="Content1" ContentPlaceHolderID="head" Runat="Server">
<script type="text/javascript" src="Jscript.js"></script>  
     <script type="text/javascript" src="jquery-1.7.1.min.js"></script> 
     <script type="text/javascript" src="jquery-ui-1.8.17.custom.css"></script>  
     <link href="~/jquery-ui-1.8.17.custom.css" rel="nofollow noreferrer noopener" rel="stylesheet" type="text/css"/>
      <script type="text/javascript">
          $(function () {
                var availableTags =  <%=test%>;

              function split(val) {
                  return val.split(/,\s*/);
              function extractLast(term) {
                  return split(term).pop();

              // don't navigate away from the field on tab when selecting an item
            .bind("keydown", function (event) {
                if (event.keyCode === $.ui.keyCode.TAB &&
                        $(this).data("autocomplete") {
                minLength: 0,
                source: function (request, response) {
                    // delegate back to autocomplete, but extract the last term
                        availableTags, extractLast(request.term)));
                focus: function () {
                    // prevent value inserted on focus
                    return false;
                select: function (event, ui) {
                    var terms = split(this.value);
                    // remove the current input
                    // add the selected item
                    // add placeholder to get the comma-and-space at the end
                    this.value = terms.join(", ");
                    return false;
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" Runat="Server">

<div class="demo" >
<div class="ui-widget">
    <label for="tags">Tag programming languages: </label>
    <input id="Text1" class="#tags" size="50" />


actually its a auto complete functionality to give tags ,the auto complete suggestions for tagging I want to get from C# code ,I took Jquery source from and then I tried to give it C# string from .cs file , I explained it with code on edited version , with C# code behind it works exactly as its in the link

Here is Solutions:

We have many solutions to this problem, But we recommend you to use the first solution because it is tested & true solution that will 100% work for you.

Solution 1

You need to serialize the C# string array into a javascript array.

Usually I create a simple static class as a wrapper.

public static class JavaScript
    public static string Serialize(object o)
        JavaScriptSerializer js = new JavaScriptSerializer();
        return js.Serialize(o);

Then you can use that class to serialize the item you need to

//C# Array(Member of asp page)
protected string[] Values = { "Sweet", "Awesome", "Cool" };

<script type="text/javascript">
    var testArray = <%=JavaScript.Serialize(this.Values) %>

Solution 2

var availableTags =  ['<%=String.join("','",test)%>'];

Solution 3

It would be something like this…

var availableTags =  ["<%= string.Join("\", \"", test) %>"];


var availableTags =  ['<%= string.Join("', '", test) %>'];

The first one would render as

var availableTags = ["Sweet", "Awesome", "Cool"];

and the second one would render as

var availableTags = ['Sweet', 'Awesome', 'Cool']; 

both of which are fine for autocomplete.

Solution 4

test property should be a string property and it should render the string which will be parsed by Js engine as an array. Try this.

Code behind property

public static string test= "['animal','usman lovely']";


 var availableTags =  <%=test%>;//No quotes

Solution 5

only use indexes to get your test string array
i have tried by giving indexes like

var availableTags =  "<%=test[0]%>";  // animal 
var availableTags =  "<%=test[1]%>";  // lovely 

Note: Use and implement solution 1 because this method fully tested our system.
Thank you 🙂

All methods was sourced from or, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0

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