find the key associated with a value in a map in typescript

You can find the key associated with a value in a Map in TypeScript in a few steps. First, you can create a function that iterates over the Map using the for...of loop syntax. For each iteration, you can check if the current value equals the target value. If there's a match, you can return the current key.

Here's an example implementation:

index.ts
function getKeyByValue(map: Map<any, any>, targetValue: any) {
  for (let [key, value] of map.entries()) {
    if (value === targetValue) {
      return key;
    }
  }
}

// Example usage
const myMap = new Map();
myMap.set('key1', 'value1');
myMap.set('key2', 'value2');
myMap.set('key3', 'value3');

console.log(getKeyByValue(myMap, 'value2')); // output: 'key2'
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In this example, we create a myMap Map with some key-value pairs. Then, we call the getKeyByValue function with myMap and the target value of 'value2'. The function iterates over the myMap Map using the for...of loop and checks if the current value is 'value2'. Once it finds a match, it returns the current key ('key2'), which is then logged to the console.