how filter method work in js code example

Example 1: filter javascript array

var words = ['spray', 'limit', 'elite', 'exuberant', 'destruction', 'present'];

const result = words.filter(word => word.length > 6);

console.log(result);

Example 2: javascript array filter

var newArray = array.filter(function(item) {
  return condition;
});

Example 3: filter items javascript

// Filter items
function filterItems(e) {
  // Convert to lowercase
  var text = e.target.value.toLowerCase();
  // Get lis
  var items = itemList.getElementsByTagName('li');
  // Convert to an array
  Array.from(items).forEach(function(item) {
    var itemName = item.firstChild.textContent;
    if (itemName.toLowerCase().indexOf(text) != -1) {
      item.style.display = 'block';
    } else {
      item.style.display = 'none';
    }
  });
}