Use Filter function :
From Eloquent Javascript Book: “Note how the filter
function, rather than deleting elements from the existing array, builds up a new array with only the elements that pass the test. This function is pure. It does not modify the array it is given.”
Example:
// Create the original array. var arr = [5, "element", 10, "the", true]; // Create an array that contains the string // values that are in the original array. var result = arr.filter( function (value) { return (typeof value === 'string'); } ); document.write(result); // Output: element, the