How to Check if a Map is Empty in Dart


How to Check if a Map is Empty in Dart ?

Answer

To check if a map is empty in Dart, you can use the isEmpty property. This property returns a boolean value indicating whether the map contains any elements.



✐ Examples

1 Checking if a Map is Empty Using isEmpty Property

We can check if a map is empty in Dart using the isEmpty property, which returns true if the map contains no elements and false otherwise.

For example,

  1. We start by declaring and initializing an empty map named myMap. In this example, the map has string keys and integer values.
  2. We use the isEmpty property to check if the map is empty. The isEmpty property returns a boolean value indicating whether the map contains any elements.
  3. We print the result to the console using the print function.

Dart Program

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

    // Check if the map is empty using isEmpty property
    bool isEmpty = myMap.isEmpty;

    // Print the result
    print('Is the map empty? $isEmpty');
}

Output

Is the map empty? true

2 Checking if a Non-Empty Map is Empty Using isEmpty Property

We can check if a non-empty map is empty in Dart using the isEmpty property, which returns false if the map contains elements.

For example,

  1. 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.
  2. We use the isEmpty property to check if the map is empty. The isEmpty property returns a boolean value indicating whether the map contains any elements.
  3. We print the result to the console using the print function.

Dart Program

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

    // Check if the map is empty using isEmpty property
    bool isEmpty = myMap.isEmpty;

    // Print the result
    print('Is the map empty? $isEmpty');
}

Output

Is the map empty? false

3 Checking if a Map is Empty After Clearing Using isEmpty Property

We can check if a map is empty in Dart after clearing its elements using the isEmpty property, which returns true if the map contains no elements.

For example,

  1. 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.
  2. We use the clear method to remove all elements from the map, making it empty.
  3. We use the isEmpty property to check if the map is empty after clearing. The isEmpty property returns a boolean value indicating whether the map contains any elements.
  4. We print the result to the console using the print function.

Dart Program

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

    // Clear the map
    myMap.clear();

    // Check if the map is empty using isEmpty property
    bool isEmpty = myMap.isEmpty;

    // Print the result
    print('Is the map empty? $isEmpty');
}

Output

Is the map empty? true

Summary

In this tutorial, we learned How to Check if a Map is Empty in Dart language with well detailed examples.




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