Dart .forEach()

The **map.forEach()** method in Dart iterates over each key-value pair in a map and applies a specified function to each pair.

Syntax

map.forEach((key, value) {
  // Your code here
});

• map: It is the map to iterate over.
• key: It represents the key in each key-value pair.
• value: It represents the value associated with the key.

The code inside the {} block is executed for each key-value pair in the map.

Alternate syntax:

map.forEach((key, value) => expression);

• expression: It is the arrow function that defines what you want to do with each key-value pair.

Example 1

The the following example, the .forEach() is used to print each key-value pair:

void main() {
  Map<String, int> ages = {
    'Alice': 25,
    'Bob': 30,
    'Charlie': 35,
  };

  ages.forEach((name, age) {
    print('$name is $age years old.');
  });
}

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The above code produces the following output:

Alice is 25 years old.
Bob is 30 years old.
Charlie is 35 years old.

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Example 2

The the following example, The .forEach() method uses an arrow function to print each product and its price in a formatted string:

void main() {
  Map<String, double> productPrices = {
    'Laptop': 999.99,
    'Smartphone': 499.99,
    'Tablet': 299.99,
  };

  productPrices.forEach((product, price) => print('$product costs \$$price'));
}

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The above code produces the following output:

Laptop costs $999.99
Smartphone costs $499.99
Tablet costs $299.99

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