How to export Grid to Word, Excel and PDF in JavaScript application?

<div id="Grid"></div>
    <script type="text/javascript">
        $(function () {
            //The datasource "window.gridData" is referred from jsondata.min.js.            
            $("#Grid").ejGrid({
                dataSource: ej.DataManager({ url: "api/Export", adaptor: "WebApiAdaptor" }),
                toolbarSettings: { showToolbar: true, toolbarItems: [ej.Grid.ToolBarItems.ExcelExport,                                                           ej.Grid.ToolBarItems.WordExport, ej.Grid.ToolBarItems.PdfExport] },
                toolbarClick: function (args) {
                    if (args.itemName == "Excel Export") {
                        args.cancel = true;
                        this.export("api/Export/ExcelExport"); // Excel Export method.
                    }
                    if (args.itemName == "Word Export") {
                        args.cancel = true;
                        this.export("api/Export/WordExport"); // Word Export method.
                    }
                    if (args.itemName == "PDF Export") {
                        args.cancel = true;
                        this.export("api/Export/PdfExport"); // PDF Export method.
                    } },
                columns: [
                        { field: "OrderID", headerText: "Order ID", width: 75, textAlign:        ej.TextAlign.Right },
                        …..
                ]
            });
        });
    </script>

    public class ExportController : ApiController
    {
        // GET api/<controller>
        NorthwindDataContext db = new NorthwindDataContext();
        public PageResult<Order> Get(ODataQueryOptions opts)
        {
            var results = opts.ApplyTo(db.Orders.AsQueryable());
            var data = db.Orders.AsQueryable();
            return new PageResult<Order>((IEnumerable<Order>)results, null, data.Count());
        }        
        public string Get(int id)
        {
            return "value";
        }        
               //Excel Export Method.
        [System.Web.Http.ActionName("ExcelExport")]
        [AcceptVerbs("POST")]
        public void ExcelExport()
        {
            string gridModel = HttpContext.Current.Request.Params["GridModel"];
            GridProperties gridProperty = ConvertGridObject(gridModel);
            ExcelExport exp = new ExcelExport();            
            IEnumerable<Order> result = db.Orders.ToList();
            exp.Export(gridProperty, result, "Export.xlsx", ExcelVersion.Excel2010, false, false, "flat-                                                                                                                                                              saffron");
        }      
               //Word Export Method.
        [System.Web.Http.ActionName("WordExport")]
        [AcceptVerbs("POST")]
        public void WordExport()
        {
            string gridModel = HttpContext.Current.Request.Params["GridModel"];
            GridProperties gridProperty = ConvertGridObject(gridModel);
            WordExport exp = new WordExport();
            IEnumerable<Order> result = db.Orders.ToList();
            exp.Export(gridProperty, result, "Export.docx", false, false, "flat-saffron");
        }
               //PDF Export Method.
        [System.Web.Http.ActionName("PdfExport")]
        [AcceptVerbs("POST")]
        public void PdfExport()
        {
            string gridModel = HttpContext.Current.Request.Params["GridModel"];
            GridProperties gridProperty = ConvertGridObject(gridModel);
            PdfExport exp = new PdfExport();           
            IEnumerable<Order> result = db.Orders.ToList();
            exp.Export(gridProperty, result, "Export.pdf");
        }      
               //Grid Model conversion Method.
        private GridProperties ConvertGridObject(string gridProperty)
        {
            JavaScriptSerializer serializer = new JavaScriptSerializer();
            IEnumerable div = (IEnumerable)serializer.Deserialize(gridProperty, typeof(IEnumerable));
            GridProperties gridProp = new GridProperties();
            foreach (KeyValuePair<string, object> ds in div)
            {
                var property = gridProp.GetType().GetProperty(ds.Key, BindingFlags.Instance |                                                                                                    BindingFlags.Public | BindingFlags.IgnoreCase);
                if (property != null)
                {
                    Type type = property.PropertyType;
                    string serialize = serializer.Serialize(ds.Value);
                    object value = serializer.Deserialize(serialize, type);
                    property.SetValue(gridProp, value, null);
                }
            }
            return gridProp;
        }