How to convert to double

Question

I validate the fonction of extract gps latitude and longitude with regex, but currently it's a String , and map_view accept only double

previous problem : how to display a regex result in flutter

I tried to use this to convert in double but it doesn't work

    RegExp regExp = new RegExp(            //Here is the regex fonction to extract long, lat        r"maps:google\.com\/maps\?q=(-?[0-9]+.[0-9]+),(-?[0-9]+.[0-9]+)",       );       var match = regExp.firstMatch(input);       group1 = match.group(1);   //match groupe seems to be an int       group2 = match.group(2);        var long2 = double.parse('$group1');       assert(long2 is double);       var lat2 = double.parse('$group2');       assert(lat2 is double); 

Answer 1

Remove the quotes from

 var long2 = double.parse('$group1'); 

to

 var long2 = double.parse($group1); 

You can also use

var long2 = double.tryParse($group1); 

or to also accept numbers without fractions

var long2 = num.tryParse($group1)?.toDouble(); 

to not get an exception when the string in $group1 can not be converted to a valid double.

Answer 2

Why not use just group1 as in double.parse(group1)