retainKeys method
Removes the key/value pairs from the map whose keys are not present in the given keys
list.
Returns a new map containing only the key/value pairs whose keys are present in the given keys
list.
Example:
Map<String, dynamic> map = {"id": 1, "name": "John", "age": 30};
var newMap = map.retainKeys(["id", "name"]);
print(newMap); // {"id": 1, "name": "John"}
Implementation
Map<T, T> retainKeys(List<T> keys) {
removeWhere((T key, T value) => !keys.contains(key));
return this;
}