Accessing Elements with indexOf
When working with arrays in JavaScript, you often need to find out if a certain value exists and, if so, where it is located. Searching for values in arrays is a common task, especially when handling lists of data such as user names, product IDs, or any collection of items. The indexOf method is a fundamental tool for this purpose. It allows you to search for a specific element and returns its position within the array, making it easier to work with dynamic data and perform checks or updates based on the presence of values.
1234567const fruits = ["apple", "banana", "cherry", "date"]; const position = fruits.indexOf("cherry"); console.log(position); // 2 const missingPosition = fruits.indexOf("orange"); console.log(missingPosition); // -1
In this example, you use indexOf to search for "cherry" in the fruits array. The method returns 2, which is the index where "cherry" is found. When searching for "orange", which is not in the array, indexOf returns -1. This behavior makes it easy to check if a value exists and to act accordingly.
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When working with arrays in JavaScript, you often need to find out if a certain value exists and, if so, where it is located. Searching for values in arrays is a common task, especially when handling lists of data such as user names, product IDs, or any collection of items. The indexOf method is a fundamental tool for this purpose. It allows you to search for a specific element and returns its position within the array, making it easier to work with dynamic data and perform checks or updates based on the presence of values.
1234567const fruits = ["apple", "banana", "cherry", "date"]; const position = fruits.indexOf("cherry"); console.log(position); // 2 const missingPosition = fruits.indexOf("orange"); console.log(missingPosition); // -1
In this example, you use indexOf to search for "cherry" in the fruits array. The method returns 2, which is the index where "cherry" is found. When searching for "orange", which is not in the array, indexOf returns -1. This behavior makes it easy to check if a value exists and to act accordingly.
Merci pour vos commentaires !
