How to Clear All Key-Value Pairs from a Map in TypeScript - Step by Step Examples



How to Clear All Key-Value Pairs from a Map in TypeScript ?

Answer

To clear all key-value pairs from a map in TypeScript, you can use the clear method. This method removes all elements from the map, leaving it empty.



✐ Examples

1 Clearing All Key-Value Pairs Using clear Method

We can clear all key-value pairs from a map in TypeScript using the clear method, which removes all elements from the map.

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 key-value pairs from the map.
  3. We print the size of the map using the size property to verify that the map is empty.

TypeScript Program

const myMap: Map<string, number> = new Map([
    ['one', 1],
    ['two', 2],
    ['three', 3]
]);

// Clear all key-value pairs using clear method
myMap.clear();

// Print the size of the map
console.log(`Size of the map after clearing: ${myMap.size}`);

Output

Size of the map after clearing: 0

2 Clearing an Already Empty Map

We can use the clear method on an already empty map in TypeScript, and it will still leave the map empty.

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 clear method to remove all key-value pairs from the map, even though it is already empty.
  3. We print the size of the map using the size property to verify that the map is still empty.

TypeScript Program

const myMap: Map<string, number> = new Map();

// Clear the map using clear method
myMap.clear();

// Print the size of the map
console.log(`Size of the map after clearing: ${myMap.size}`);

Output

Size of the map after clearing: 0

3 Clearing a Map After Inserting Elements

We can insert key-value pairs into a map and then clear all key-value pairs using the clear method.

For example,

  1. We start by declaring and initializing a map named myMap and inserting some key-value pairs into it. In this example, the map has string keys and integer values.
  2. We use the clear method to remove all key-value pairs from the map.
  3. We print the size of the map using the size property to verify that the map is empty.

TypeScript Program

const myMap: Map<string, number> = new Map();
myMap.set('one', 1);
myMap.set('two', 2);
myMap.set('three', 3);

// Clear all key-value pairs using clear method
myMap.clear();

// Print the size of the map
console.log(`Size of the map after clearing: ${myMap.size}`);

Output

Size of the map after clearing: 0

Summary

In this tutorial, we learned How to Clear All Key-Value Pairs from a Map in TypeScript language with well detailed examples.




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  11. How to Remove a Key-Value Pair from a Map in TypeScript ?
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  26. How to Filter a Map Based on Keys in TypeScript ?
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  28. How to Reduce Values in a Map to a Single Value in TypeScript ?
  29. How to Convert an Array of Key-Value Pairs to a Map in TypeScript ?
  30. How to Convert a Map to a JSON String in TypeScript ?
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