Check browser in sharepoint pages

function BrowserCheck()
{

   if (navigator.appName == "Microsoft Internet Explorer") {        
    }
    else {      
        alert("Please login to Microsoft Internet Explorer for submitting PM's Weekly Status Sheet. You will be redirected to a blank page");
        window.location = "../../Redirect.aspx";
        //var date_WeekStartDate_1=document.getElementById('<%=WeekStartDate_1.Controls[0].ClientID%>');
//var date_WeekEndDate_1=document.getElementById('<%=WeekEndDate_1.Controls[0].ClientID%>');

        return false;
    }
}