To filter a map based on values in JavaScript, you can iterate over the map and add key-value pairs that meet the filter criteria to a new map. This method allows you to create a subset of the original map based on specific value conditions.
We can filter a map based on a range of values in JavaScript by iterating over the map and adding key-value pairs that fall within the specified range to a new map.
For example,
myMap
with some key-value pairs. In this example, the map has integer keys and integer values.filteredMap
to store the filtered key-value pairs.forEach
method and check if each value falls within the specified range.filteredMap
.console.log
function to verify the filtering.const myMap = new Map([
[1, 10],
[2, 20],
[3, 30],
[4, 40],
[5, 50]
]);
// Declare an empty map to store the filtered key-value pairs
const filteredMap = new Map();
// Define the value range
const lowerBound = 20;
const upperBound = 40;
// Iterate over the original map and filter based on the value range
myMap.forEach((value, key) => {
if (value >= lowerBound && value <= upperBound) {
filteredMap.set(key, value);
}
});
// Print the filtered map
console.log('Filtered Map by Value Range:', Array.from(filteredMap));
Filtered Map by Value Range: [[2, 20], [3, 30], [4, 40]]
We can filter a map based on specific values in JavaScript by iterating over the map and adding key-value pairs that match the specified values to a new map.
For example,
myMap
with some key-value pairs. In this example, the map has integer keys and integer values.filteredMap
to store the filtered key-value pairs.forEach
method and check if each value matches one of the specified values.filteredMap
.console.log
function to verify the filtering.const myMap = new Map([
[1, 10],
[2, 20],
[3, 30],
[4, 40],
[5, 50]
]);
// Declare an empty map to store the filtered key-value pairs
const filteredMap = new Map();
// Define the specific values to filter by
const valuesToFilter = new Set([10, 30, 50]);
// Iterate over the original map and filter based on the specific values
myMap.forEach((value, key) => {
if (valuesToFilter.has(value)) {
filteredMap.set(key, value);
}
});
// Print the filtered map
console.log('Filtered Map by Specific Values:', Array.from(filteredMap));
Filtered Map by Specific Values: [[1, 10], [3, 30], [5, 50]]
We can filter a map with string values based on a specific prefix in JavaScript by iterating over the map and adding key-value pairs that have values starting with the given prefix to a new map.
For example,
myMap
with some key-value pairs. In this example, the map has integer keys and string values.filteredMap
to store the filtered key-value pairs.forEach
method and check if each value starts with the specified prefix.filteredMap
.console.log
function to verify the filtering.const myMap = new Map([
[1, 'apple'],
[2, 'banana'],
[3, 'apricot'],
[4, 'carrot'],
[5, 'blueberry']
]);
// Declare an empty map to store the filtered key-value pairs
const filteredMap = new Map();
// Define the prefix to filter by
const prefix = 'ap';
// Iterate over the original map and filter based on the prefix
myMap.forEach((value, key) => {
if (value.startsWith(prefix)) {
filteredMap.set(key, value);
}
});
// Print the filtered map
console.log('Filtered Map by Prefix:', Array.from(filteredMap));
Filtered Map by Prefix: [[1, 'apple'], [3, 'apricot']]
In this tutorial, we learned How to Filter a Map Based on Values in JavaScript language with well detailed examples.