Set Current date and time in feild using Javascript in crm 2015

function settodaydate()
{
var currentDateTime = new Date();
Xrm.Page.getAttribute("fieldname").setValue(currentDateTime);
}

make whole form fields readonly using javascript in CRM 2015

function MarkAllFieldReadOnly() {// this function will make whole form fields readonly

Xrm.Page.ui.controls.forEach(function (control, index) {

try{

control.setDisabled(true);

}

catch (e)

{

}

});

}