Установите поля даты MIN в текущую дату
// Use Javascript
var today = new Date();
var dd = today.getDate();
var mm = today.getMonth()+1; //January is 0 so need to add 1 to make it 1!
var yyyy = today.getFullYear();
if(dd<10){
dd='0'+dd
}
if(mm<10){
mm='0'+mm
}
today = yyyy+'-'+mm+'-'+dd;
document.getElementById("datefield").setAttribute("min", today);
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