How to convert Hexadecimal to Double in Dart?-CodePudding

By receiving coordinates encoded as hex, how could I convert them into a double value so that I get a true value of those coordinates? I already tried converting from hex to int and then to double, but I couldn't get the correct value. Is there a Dart package that could this?

I tried the double.parse() return Invalid Double Exception

For reference I have the following hex as a String:

4044B84189374BC1

That should return something like this:

41.43949999999996

I tested with those online converters but I couldn't find a way to do this in Dart language

CodePudding user response：

It is a bit wonky but the following seems to do the trick:

import 'dart:typed_data';

void main() {
  print(convert('4044B84189374BC1')); // 41.43949999999996
}

double convert(String hexString) =>
    (ByteData(8)..setUint64(0, int.parse(hexString, radix: 16))).getFloat64(0);

The idea is that I assume the hex string are an normal integer. I then take the 64-bit bits from this int and puts into a bytebuffer and then read this buffer as if it contains a double.