var posImg = 0;
var navLeft = "#ctl00_ContentPlaceHolder1_modalComoChegar_navLeftGaleria";
var navRight = "#ctl00_ContentPlaceHolder1_modalComoChegar_navRightGaleria";


function avancarFotoGaleria() {   

    if (posImg < imgGaleria.length) {
        $(navLeft).removeClass('navInativoLeft');
        $(navLeft).attr('href', 'javascript: voltarFotoGaleria();');
        $(navLeft).css('cursor', 'pointer');
        posImg++;                 
    }

    document.getElementById('ctl00_ContentPlaceHolder1_modalComoChegar_imgGaleria').src = imgGaleria[posImg];
    $('#ctl00_ContentPlaceHolder1_modalComoChegar_lblLegenda').text(lblLegenda[posImg].toString());
    
    if (posImg + 1 >= imgGaleria.length){
        $(navRight).addClass('navInativoRight');
        $(navRight).attr('href', 'javascript:;');
        $(navRight).css('cursor','default');    
    }
    
}

function voltarFotoGaleria() {

    if (posImg > 0) {
        $(navRight).removeClass('navInativoRight');
        $(navRight).attr('href', 'javascript: avancarFotoGaleria();');
        $(navRight).css('cursor', 'pointer');
        posImg--;
    }

    document.getElementById('ctl00_ContentPlaceHolder1_modalComoChegar_imgGaleria').src = imgGaleria[posImg];
    $('#ctl00_ContentPlaceHolder1_modalComoChegar_lblLegenda').text(lblLegenda[posImg].toString());

    if (posImg == 0) {        
       $(navLeft).addClass('navInativoLeft');
       $(navLeft).attr('href', 'javascript:;');
       $(navLeft).css('cursor', 'default');    
    }
}