var win;
    function Testimonial(){
        if(win&&!win.closed){
            win.focus();
            return;
        }
        var x=(screen.width-450)/2;
        var y=(screen.height-350)/2;
        win = window.open("/Testimonial/_Testimonial.htm",null,
        "height=350,width=450,left="+ x +",top=" + y +",status=yes,toolbar=no,menubar=no,location=no");
    }