readUint64 method
Implementation
BigInt readUint64() {
var data = _data.sublist(offset, offset + 8);
offset += 8;
var n = BigInt.from(0);
for (var i = 0; i < data.length; i++) {
var d = BigInt.from(2).pow((data.length - i - 1) * 8);
n = n + BigInt.from(data[i]) * d;
}
return n;
}