To get the first n elements of an array we can use many logical methods, but underscore.js a library of javascript has provided a function called _.first() to get the first n elements of javascript. It is a widely used method to deal with arrays.
syntax
_.first(array,n);
it takes an array and a number as parameters. It takes a number as a parameter so as to display those number of first n elements as output.
Example-1
In the following example, only an array is passed as an argument so only the first element i.e zeroth indexed value is displayed as the output.
<html>
<body>
<script
src="//cdnjs.cloudflare.com/ajax/libs/lodash.js/0.10.0/lodash.min.js"></script>
</head>
<body>
<script>
var res = JSON.stringify(_.first([
{name: 'Dhoni', age: 38},
{name: 'kohli', age: 35},
{name: 'Rohit', age: 32},
{name: 'Dhawan', age: 27}])
);
document.write((res));
</script>
</body>
</html>Output
{"name":"Dhoni","age":38}Example-2
In the following example, along with array, a number is also passed so that we can get those number of elements from the array as shown in the output.
<html>
<body>
<script
src="//cdnjs.cloudflare.com/ajax/libs/lodash.js/0.10.0/lodash.min.js"></script>
</head>
<body>
<script>
var res = JSON.stringify(_.first([
{name: 'Dhoni', age: 38},
{name: 'kohli', age: 35},
{name: 'Rohit', age: 32},
{name: 'Dhawan', age: 27}],2)
);
document.write((res));
</script>
</body>
</html>Output
[{"name":"Dhoni","age":38},{"name":"kohli","age":35}]