[CLOSED] Send Json object with get value with loaders

[Tactem]

i have json object and some parameters in js function

i want to send in my controller action all of variable but json object is always null.
i use actually my get values with url

js function

var json = JSON.stringify(bandeau);
    var newTab = Ext.create("Ext.container.Container", {
        id: idTab,
        renderTo: Ext.getBody(),
        hidden: true,
        layout: 'fit',
        border: false,
        loader: {
            renderer: "frame",
            url: AppPath + "DashBoardGenerator/LoadTable?tableName=" + tableName + "&idProc=" + id + "&clientId=" + clientId + "&currencyId=" + currencyId,
            loadMask: {
                showMask: true,
                msg: TIO.Resources.PreparingDisplay
            },
            params:
            {
                bandeau: json
            }

        }
    })

action controller

        public ActionResult LoadTable(string tableName, int idProc, int clientID, int? currencyId, Headband bandeau)
        {

}

use parameter value

private DashBoardExtendedParametersModel GetDashBoardExtendedParametersModelByUrl(Uri url)
        {
            string queryString = (!string.IsNullOrEmpty(url.Query)) ? url.Query.Remove(0, 1) : string.Empty;// supression du ?
            if (!string.IsNullOrEmpty(queryString))
            {
                Dictionary<string, string> uriParameters = new Dictionary<string, string>();
                queryString.Split('&').ToList().ForEach(p => uriParameters.Add(p.Split('=')[0], p.Split('=')[1]));

                return new DashBoardExtendedParametersModel
                {
                    ClientId = int.Parse(uriParameters["clientId"]),
                    CurrencyId = (uriParameters["currencyId"] != "null") ? int.Parse(uriParameters["currencyId"]) : (int?)null,
                    TableName = uriParameters["tableName"],
                    IdProc = int.Parse(uriParameters["idProc"])
                };
            }


            return null;
        }

Regards