Dart: Collection Set

Identifier = new Set()

or

Identifier = new Set.from(Iterable)
# HashMap
Identifier= new HashMap()

Example

import 'dart:collection'; 
main() { 
   var accounts = new HashMap(); 
   accounts['dept']='BA'; 
   accounts['name']='Kim'; 
   accounts['email']='kim@123.com'; 
   print('Map after adding  entries :${accounts}'); 
}

=> output

Map after adding entries :{email: kim@123.com, dept: BA, name: Kim}

Adding Multiple Values to a HashMap

HashMap.addAll(Iterable)

Example

import 'dart:collection'; 
main() { 
   var accounts = new HashMap(); 
   accounts.addAll({'dept':'BA','email':'kim@123.com'}); 
   print('Map after adding  entries :${accounts}'); 
}

=> output

Map after adding  entries :{email: kim@123.com, dept: BA} 

Removing Values from a HashMap

import 'dart:collection'; 
main() { 
   var accounts = new HashMap(); 
   accounts['dept'] = 'BA'; 
   accounts['name'] = 'Kim'; 
   accounts['email'] = 'kim@123.com'; 
   print('Map after adding  entries :${accounts}');
   accounts.remove('dept'); 
   print('Map after removing  entry :${accounts}');  
   accounts.clear(); 
   print('Map after clearing entries :${accounts}'); 
} 

=> output

Map after adding  entries :{email: kim@123.com, dept: BA, name: Kim} 
Map after removing  entry :{email: kim@123.com, name: Kim} 
Map after clearing entries :{}
# HashSet
Identifier = new HashSet() 

Adding Multiple Values to a HashSet

addAll() function allows adding multiple values to the HashSet.

import 'dart:collection'; 
void main() { 
   Set numberSet = new  HashSet(); 
   numberSet.addAll([10,20,30]); 
   print("Default implementation :${numberSet.runtimeType}"); 
   for(var no in numberSet){ 
      print(no); 
   } 
}

=> output 

Default implementation :_HashSet 
200 
300 
100 

Removing Values from a HashSet

remove() function removes the value passed to it.

clear() function removes all the entries from the HashSet.

import 'dart:collection'; 
void main() { 
   Set numberSet = new  HashSet(); 
   numberSet.addAll([10,20,30]); 
   print("Printing hashet.. ${numberSet}");  
   numberSet.remove(10); 
   print("Printing hashet.. ${numberSet}");  
   numberSet.clear(); 
   print("Printing hashet.. ${numberSet}"); 
} 

=> output 

Printing hashet.. {20, 30, 10} 
Printing hashet.. {20, 30} 
Printing hashet.. {}

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