Storage class Null safety

The type used by the Window.localStorage and Window.sessionStorage properties. Storage is implemented as a Map<String, String>.

To store and get values, use Dart's built-in map syntax:

window.localStorage['key1'] = 'val1';
window.localStorage['key2'] = 'val2';
window.localStorage['key3'] = 'val3';
assert(window.localStorage['key3'] == 'val3');

You can use Map APIs such as containsValue(), clear(), and length:

assert(window.localStorage.containsValue('does not exist') == false);
window.localStorage.clear();
assert(window.localStorage.length == 0);
Mixed in types

Properties

entries Iterable<MapEntry<String, String>>
The map entries of this.
read-only, inherited
hashCode int
The hash code for this object.
read-only, inherited
isEmpty bool
Whether there is no key/value pair in the map.
read-only, override
isNotEmpty bool
Whether there is at least one key/value pair in the map.
read-only, override
keys Iterable<String>
The keys of this.
read-only, override
length int
The number of key/value pairs in the map.
read-only, override
runtimeType Type
A representation of the runtime type of the object.
read-only, inherited
values Iterable<String>
The values of this.
read-only, override

Methods

addAll(Map<String, String> other) → void
Adds all key/value pairs of other to this map.
override
addEntries(Iterable<MapEntry<String, String>> newEntries) → void
Adds all key/value pairs of newEntries to this map.
inherited
cast<RK, RV>() Map<RK, RV>
Provides a view of this map as having RK keys and RV instances, if necessary.
inherited
clear() → void
Removes all entries from the map.
override
containsKey(Object? key) bool
Whether this map contains the given key.
override
containsValue(Object? value) bool
Whether this map contains the given value.
override
forEach(void f(String key, String value)) → void
Applies action to each key/value pair of the map.
override
map<K2, V2>(MapEntry<K2, V2> transform(String key, String value)) Map<K2, V2>
Returns a new map where all entries of this map are transformed by the given convert function.
inherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed.
inherited
putIfAbsent(String key, String ifAbsent()) String
Look up the value of key, or add a new entry if it isn't there.
override
remove(Object? key) String?
Removes key and its associated value, if present, from the map.
override
removeWhere(bool test(String key, String value)) → void
Removes all entries of this map that satisfy the given test.
inherited
toString() String
A string representation of this object.
inherited
update(String key, String update(String value), {String ifAbsent()?}) String
Updates the value for the provided key.
inherited
updateAll(String update(String key, String value)) → void
Updates all values.
inherited

Operators

operator ==(Object other) bool
The equality operator.
inherited
operator [](Object? key) String?
The value for the given key, or null if key is not in the map.
override
operator []=(String key, String value) → void
Associates the key with the given value.
override