ProgramGuruTo set a default value for a key in a map in TypeScript, you can use the set method combined with the has method. This approach checks if the key exists using the has method, and if it does not, uses the set method to insert the key with the default value.
We can set a default value for a key in a map in TypeScript by checking if the key exists using the has method and then using the set method to insert the key-value pair if the key does not exist.
For example,
myMap with some key-value pairs. In this example, the map has string keys and integer values.has method to check if the key exists in the map. If the key does not exist, we use the set method to insert the key with the default value.forEach method and console.log.let myMap: Map<string, number> = new Map([
['one', 1],
['two', 2],
['three', 3]
]);
// Set a default value using has and set methods
if (!myMap.has('four')) {
myMap.set('four', 4);
}
// Print the updated map
myMap.forEach((value, key) => {
console.log(`${key}: ${value}`);
});one: 1 two: 2 three: 3 four: 4
We can set multiple default values for keys in a map in TypeScript by using the has method to check if the keys exist and then using the set method to insert the key-value pairs if the keys do not exist.
For example,
myMap with some key-value pairs. In this example, the map has string keys and integer values.has method to check if the keys exist in the map. If the keys do not exist, we use the set method to insert the keys with the default values.forEach method and console.log.let myMap: Map<string, number> = new Map([
['one', 1],
['two', 2],
['three', 3]
]);
// Set multiple default values using has and set methods
if (!myMap.has('four')) {
myMap.set('four', 4);
}
if (!myMap.has('five')) {
myMap.set('five', 5);
}
// Print the updated map
myMap.forEach((value, key) => {
console.log(`${key}: ${value}`);
});one: 1 two: 2 three: 3 four: 4 five: 5
We can set a default value for a key in a map in TypeScript by using the has method to check if the key exists and then using the set method to insert the key-value pair if the key does not exist, based on a condition.
For example,
myMap with some key-value pairs. In this example, the map has string keys and integer values.has method to check if the key exists in the map. If the key does not exist, we use the set method to insert the key with the default value based on a condition.forEach method and console.log.let myMap: Map<string, number> = new Map([
['one', 1],
['two', 2],
['three', 3]
]);
// Set a default value conditionally using has and set methods
if (!myMap.has('four')) {
myMap.set('four', myMap.get('four') || 4);
}
// Print the updated map
myMap.forEach((value, key) => {
console.log(`${key}: ${value}`);
});one: 1 two: 2 three: 3 four: 4
In this tutorial, we learned How to Set a Default Value for a Key in a Map in TypeScript language with well detailed examples.