I have a cookie set with javascript, I created it like this:
document.cookie='gravado=sim'
I do not know how to check if it exists. I need to do a check because if it does not exist, I'll redirect to another page, I also need to know how I can destroy this cookie.
You can check this way
if (document.cookie.indexOf("gravado") < 0) {
alert("O cookie não existe vou criar");
document.cookie="gravado=sim";
}
else {
alert("Já está gravado, vou eliminar");
document.cookie ="gravado=; expires=Thu, 01 Jan 1970 00:00:01 GMT;";
}