find first match item in object foresch in javascript

To find the first matching item in an object using forEach in JavaScript, you can use the Object.keys() method to get all the property names of the object, and iterate over them using forEach. Then, you can check if the value of the property is equal to the value you are looking for. If it is, you can return the key of the property.

Here's an example:

index.tsx
const obj = {a: 1, b: 2, c: 3};

let foundKey = null;
Object.keys(obj).forEach(key => {
  if (obj[key] === 2) {
    foundKey = key;
    return; // exits the forEach loop early
  }
});

console.log(foundKey); // logs 'b'
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In this example, we have an object with properties a, b, and c. We want to find the first property that has a value of 2. We use Object.keys() to get an array of the keys of the object, and then use forEach to iterate over them. Inside the forEach callback, we check if the value of the property is equal to 2. If it is, we set the foundKey variable to the key of the property, and return from the forEach loop early (since we have found the first matching item). Finally, we log the foundKey variable to the console.