Control the return button evendo from the browser

Question

I’m using the function in jQuery onbeforeunload but it is being activated by browser back (Back Button).

I would like to know how to control the event back from the browser, I have tried several possible solutions but none worked.

My goal is to undo the action of onbeforeunload when the browser back button is activated, so that the message does not appear.

var botao_voltar == MANEIRA DE CAPTURAR O EVENTO;

if (botao_voltar == false)
{
    onbeforeunload = function()
    {
        return 'MENSAGEM PARA O USUÁRIO';
    }
}

Answer 1

I will give a solution that also involves some other problems that I have suffered with my client and, that many people have said that it is impossible to circumvent.

Well, it follows the commented code, where it only allows the outgoing message the page is displayed when the Reload button is clicked, or when the client goes to a new page. For example by entering a new address in the URL bar..

BUT IF HE SQUEEZES F5, or CTRL+R, or Backspace, or give click on the Back button of the browser it performs that action, but does not display the page output alert message.

in the case in our company, it meets:

       // para o botao voltar do navegador

    detectedBrowser= Qual_Eh_o_Seu_Browser?;

            if(detectedBrowser==InternetExplorer){history.pushState( "nohb", null, "URL_Corretaaaaa" );}
            else    {history.pushState( "nohb", null, "" );}

            window.onpopstate = function(event) {               // JS version
        //  $(window).on( "popstate", function(event){          // Jquery version
                console.log('MESSAGE  213 = ' + flag_beforeunload ) 
                if( !event.state ){                             // JS version
        //      if( !event.originalEvent.state ){               // Jquery version

                        // para desabilitar o botao BACK do navegador, descomente as linhas abaixo:
                        //  history.pushState( "nohb", null, "" );
                        //  return;

                        // para tratar o evento UnBeforeUnload voce tem as linhas abaixo..  modifique conforme sua necessidade... neste exemplo ele so volta uam pagina, sem pop up.
                            flag_beforeunload=false;
                         window.history.back();


                }
            };


//
//escutando o teclado
//

    document.onkeydown = KeyCheck;
    function KeyCheck(e) {
        var key = (window.event) ? event.keyCode : e.keyCode;
        if(key==116) {flag_beforeunload=false;}     
        if(key==8) {flag_beforeunload=false;}       
        if (e.keyCode == 82 && e.ctrlKey) {flag_beforeunload=false;}        
        if(e.keyCode == 91) {flag_beforeunload=false;}      // safari
        if (e.keyCode == 82) {flag_beforeunload=false;}     // safari

        document.getElementById("container").innerHTML = "key = "+key + " - " + flag_beforeunload;
    }



//
// o evento UnBeforeUnload
//
        window.onbeforeunload = function(e){
            var msg = 'Deseja mesmo sair?';
            e = e || window.event;

            if(e)
                if (flag_beforeunload == true) {
                    return msg;
                }
        }

Please use carefully, remember that is an example.... then this is far from perfect!! must be suitable to your needs thank you!

It works well on Chrome, Jah in firefox, iexplorer and safari I’m still seeing ways to work.

ps: also put in the fidle, but on this page not working through.. please knife site for testing...