Dart Collections: Map Operations | Map Extensions | Map Methods
Dart provides several operations, extensions, and methods for working with Map
collections. Let's explore some of them:
Map Operations:
1. Adding a Key-Value Pair:
- You can add a new key-value pair to a map using the square bracket notation.
Map<String, int> ages = {'Alice': 25, 'Bob': 30};
ages['Charlie'] = 22;
2. Updating a Value for a Key:
- You can update the value associated with a key.
Map<String, int> ages = {'Alice': 25, 'Bob': 30};
ages['Alice'] = 26;
3. Removing a Key-Value Pair:
- You can remove a key-value pair from the map using the
remove
method.
Map<String, int> ages = {'Alice': 25, 'Bob': 30};
ages.remove('Bob');
Map Extensions:
1. forEach:
- Iterates through the map and applies a function to each key-value pair.
Map<String, int> ages = {'Alice': 25, 'Bob': 30};
ages.forEach((key, value) {
print('$key\'s age is $value');
});
Map Methods:
1. containsKey:
- Checks if the map contains a specific key.
Map<String, int> ages = {'Alice': 25, 'Bob': 30};
print(ages.containsKey('Alice')); // Output: true
2. containsValue:
- Checks if the map contains a specific value.
Map<String, int> ages = {'Alice': 25, 'Bob': 30};
print(ages.containsValue(25)); // Output: true
3. keys:
- Returns an iterable of all keys in the map.
Map<String, int> ages = {'Alice': 25, 'Bob': 30};
print(ages.keys); // Output: (Alice, Bob)
4. values:
- Returns an iterable of all values in the map.
Map<String, int> ages = {'Alice': 25, 'Bob': 30};
print(ages.values); // Output: (25, 30)
5. isEmpty:
- Checks if the map is empty.
Map<String, int> ages = {};
print(ages.isEmpty); // Output: true
6. isNotEmpty:
- Checks if the map is not empty.
Map<String, int> ages = {'Alice': 25};
print(ages.isNotEmpty); // Output: true
These are some common operations, extensions, and methods you can use with Dart Map
collections. Depending on your specific needs, you can choose the appropriate operation or method for your map manipulation.
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Written by
Vinit Mepani
Vinit Mepani
"Hello World, I'm Vinit Mepani, a coding virtuoso driven by passion, fueled by curiosity, and always poised to conquer challenges. Picture me as a digital explorer, navigating through the vast realms of code, forever in pursuit of innovation. In the enchanting kingdom of algorithms and syntax, I wield my keyboard as a magical wand, casting spells of logic and crafting solutions to digital enigmas. With each line of code, I embark on an odyssey of learning, embracing the ever-evolving landscape of technology. Eager to decode the secrets of the programming universe, I see challenges not as obstacles but as thrilling quests, opportunities to push boundaries and uncover new dimensions in the realm of possibilities. In this symphony of zeros and ones, I am Vinit Mepani, a coder by passion, an adventurer in the digital wilderness, and a seeker of knowledge in the enchanting world of code. Join me on this quest, and let's create digital wonders together!"