jQuery Autocomplete TextBox from multiple columns using jQuery Ajax in ASP.Net

Hi ,

Refer the Below Articles links also refer the below code for your reference.

1. Display No results found message (No match found message) in jQuery AutoComplete
2. Implement jQuery AutoComplete TextBox from database using AJAX PageMethods in ASP.Net

HTML

Default.aspx

Enter search term:
<input type="text" id="txtSearch" />
<div>
    <style type="text/css">
        body
        {
            font-family: Arial;
            font-size: 10pt;
        }
    </style>
    <script src="http://ajax.aspnetcdn.com/ajax/jQuery/jquery-1.10.0.min.js" type="text/javascript"></script>
    <script src="http://ajax.aspnetcdn.com/ajax/jquery.ui/1.9.2/jquery-ui.min.js" type="text/javascript"></script>
    <link href="http://ajax.aspnetcdn.com/ajax/jquery.ui/1.9.2/themes/blitzer/jquery-ui.css"
        rel="Stylesheet" type="text/css" />
    <script type="text/javascript">
        $(function () {
            $("[id*=txtSearch]").autocomplete({
                source: function (request, response) {
                    $.ajax({
                        url: 'Default.aspx/GetSearchResults',
                        data: "{ 'prefix': '" + request.term + "'}",
                        dataType: "json",
                        type: "POST",
                        contentType: "application/json; charset=utf-8",
                        success: function (data) {
                            if (data.d.length > 0) {
                                response($.map(data.d, function (item) {
                                    return {
                                        label: item,
                                        val: item
                                    };
                                }))
                            } else {
                                response([{ label: 'No results found.', val: -1}]);
                            }
                        }
                    });
                },
                select: function (e, u) {
                    if (u.item.val == -1) {
                        return false;
                    }
                }
            });
        });
    </script>
</div>

Code

Default.aspx.cs

[System.Web.Services.WebMethod]
[System.Web.Script.Services.ScriptMethod()]
public static string[] GetSearchResults(string prefix)
{
    List<string> searchResult = new List<string>();
    using (SqlConnection conn = new SqlConnection())
    {
        conn.ConnectionString = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
        using (SqlCommand cmd = new SqlCommand())
        {
            cmd.CommandText = @"SELECT FirstName Result FROM Employees
                                WHERE FirstName like @SearchText + '%'
                                UNION ALL
                                SELECT City Result FROM Employees
                                WHERE City Like @SearchText + '%'
                                UNION ALL
                                SELECT HomePhone Result FROM Employees
                                WHERE HomePhone like '%' + @SearchText + '%'";

            cmd.Parameters.AddWithValue("@SearchText", prefix);
            cmd.Connection = conn;
            conn.Open();
            using (SqlDataReader sdr = cmd.ExecuteReader())
            {
                while (sdr.Read())
                {
                    searchResult.Add(sdr["Result"].ToString());
                }
            }
            conn.Close();
        }
    }
    return searchResult.ToArray();
}

Screenshot