How to Convert a Map to an Array of Key-Value Pairs in Dart

How to Convert a Map to an Array of Key-Value Pairs in Dart ?

Answer

To convert a map to an array of key-value pairs in Dart, you can use the entries property to get an iterable of map entries and then convert this iterable to a list. This provides a convenient way to extract all key-value pairs from the map.

✐ Examples

1 Converting a Map to an Array of Key-Value Pairs Using entries Property

We can convert a map to an array of key-value pairs in Dart using the entries property, which provides an iterable of all entries in the map. We can then convert this iterable to a list.

For example,

We start by declaring and initializing a map named myMap with some key-value pairs. In this example, the map has string keys and integer values.
We use the entries property to get an iterable of the key-value pairs in the map.
We convert the iterable to a list using the toList method.
We store the list of key-value pairs in a variable named entriesList.
We print the key-value pairs to the console using a for loop and the print function to verify the conversion.

Dart Program

void main() {
    // Declare and initialize a map
    Map<String, int> myMap = {
        'one': 1,
        'two': 2,
        'three': 3
    };

    // Convert map to an array of key-value pairs
    List<MapEntry<String, int>> entriesList = myMap.entries.toList();

    // Print the key-value pairs
    print('Key-Value Pairs:');
    for (var entry in entriesList) {
        print('${entry.key}: ${entry.value}');
    }
}

Output

Key-Value Pairs:
one: 1
two: 2
three: 3

2 Converting an Empty Map to an Array of Key-Value Pairs

We can also convert an empty map to an array of key-value pairs in Dart using the entries property, which returns an empty list when the map is empty.

For example,

We start by declaring an empty map named emptyMap with string keys and integer values.
We use the entries property to get an iterable of the key-value pairs in the empty map.
We convert the iterable to a list using the toList method.
We store the list of key-value pairs in a variable named emptyEntriesList.
We print the key-value pairs to the console using the print function to verify that the list is empty.

Dart Program

void main() {
    // Declare an empty map
    Map<String, int> emptyMap = {};

    // Convert empty map to an array of key-value pairs
    List<MapEntry<String, int>> emptyEntriesList = emptyMap.entries.toList();

    // Print the key-value pairs
    print('Key-Value Pairs: $emptyEntriesList');
}

Output

Key-Value Pairs: []

3 Converting a Map to an Array of Key-Value Pairs After Adding Elements

We can convert a map to an array of key-value pairs in Dart after adding elements using the entries property, which provides an updated iterable of all key-value pairs in the map.

For example,

We start by declaring an empty map named dynamicMap with string keys and integer values.
We add some key-value pairs to the map using the map's index notation.
We use the entries property to get an iterable of the key-value pairs in the map after adding elements.
We convert the iterable to a list using the toList method.
We store the list of key-value pairs in a variable named dynamicEntriesList.
We print the key-value pairs to the console using a for loop and the print function to verify the updated list of key-value pairs.

Dart Program

void main() {
    // Declare an empty map
    Map<String, int> dynamicMap = {};

    // Add elements to the map
    dynamicMap['one'] = 1;
    dynamicMap['two'] = 2;
    dynamicMap['three'] = 3;

    // Convert map to an array of key-value pairs after adding elements
    List<MapEntry<String, int>> dynamicEntriesList = dynamicMap.entries.toList();

    // Print the key-value pairs
    print('Key-Value Pairs:');
    for (var entry in dynamicEntriesList) {
        print('${entry.key}: ${entry.value}');
    }
}

Output

Key-Value Pairs:
one: 1
two: 2
three: 3

Summary

In this tutorial, we learned How to Convert a Map to an Array of Key-Value Pairs in Dart language with well detailed examples.

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How to Convert a Map to an Array of Key-Value Pairs in Dart