Extract template tags {{..}} from a string in flutter - flutter

Question

I need to extract squiggly bracketed template tags from a string. For example:
String str="Hello {{user}}, your reference is {{ref}}"
I would like a to extract the tags in-between the {{..}} into an List. For example:
["user","ref"]
How can I do this, for example with a Regx - I would need to ignore any whitespace in-side the brackets for example {{ user}} would need to return "user".
This question is exactly same as this que.. Want code for flutter dart.

Answer 1

You can use this regex
void main() {
RegExp re = RegExp(r'{{([^]*?)}}');
String data = "Hello {{user}}, your reference is {{ref}}";
var match = re.firstMatch(data);
if (match != null) print(match.group(1));
List something = re.allMatches(data).map((m)=>m[1]).toList();
print(something);
}
OUtput
user
[user, ref]

Answer 2

void main() {
String str="Hello {{user}}, your reference is {{ref}}";
List<String> lstr = getStringBetweenBracket(str);
print(lstr);
}
List<String> getStringBetweenBracket(String str) {
List<String> rstr = [];
var j = str.splitMapJoin(new RegExp(r'\{\{(.*?)\}\}'), onMatch: (e) {
if( e.group(0) != null)
return e.group(0)!.replaceAll("{{","").replaceAll("}}","")+",";
else
return "";
}, onNonMatch: (e) { return ""; });
if(j != "") {
rstr = j.split(",");
rstr.removeAt(rstr.length-1);
}
return rstr;
}

Answer 3

you can do this way get array of data
void main() {
String str="Hello {{user}}, your reference is {{ref}}";
var parts = str.split(' ');
print(parts);
print(parts[1]);
}
void main(){
String str = 'HelloTutorialKart.';
int startIndex = 5;
int endIndex = 13;
//find substring
String result = str.substring(startIndex, endIndex);
print(result);
}
output
Tutorial