Sorting
Sorting is nothing but displaying elements in ascending or descending order. Array.sort() function is to sort the array according to the compare() function in JavaScript.
a) In the given program we are going to sort the array by age property in descending order.
Example
<html>
<body>
<script>
var persons = [
{ name: 'rajesh', birthdate: 1845, death: 1875 },
{ name: 'Bharat', birthdate: 1909, death: 1917},
{ name: 'baba', birthdate: 1950, death: 1972 },
{ name: 'Tanish', birthdate: 2039, death: 2067 },
{ name: 'rahim', birthdate: 1989, death: 2049 }
]
var sortedArray = persons.sort(function(a,b) {
var lastPerson = a.death - a.birthdate;
var nextPerson = b.death - b.birthdate;
if (lastPerson > nextPerson) {
return -1;
} else {
return 1;
}
});
console.log(sortedArray);
</script>
</body>
</html>Output in browser console
{name: "rahim", birthdate: 1989, death: 2049}
{name: "rajesh", birthdate: 1845, death: 1875}
{name: "Tanish", birthdate: 2039, death: 2067}
{name: "baba", birthdate: 1950, death: 1972}
{name: "Bharat", birthdate: 1909, death: 1917}b) Here sorting is done so as to arrange the array in ascending order using age property
Example
<html>
<body>
<script>
var persons = [
{ name: 'rajesh', birthdate: 1845, death: 1875 },
{ name: 'Bharat', birthdate: 1909, death: 1917},
{ name: 'baba', birthdate: 1950, death: 1972 },
{ name: 'Tanish', birthdate: 2039, death: 2067 },
{ name: 'rahim', birthdate: 1989, death: 2049 }
]
var sortedArray = persons.sort(function(a,b) {
var lastPerson = a.death - a.birthdate;
var nextPerson = b.death - b.birthdate;
if (lastPerson < nextPerson) {
return -1;
} else
{
return 1;
}
});
console.log(sortedArray);
</script>
</body>
</html>Output in browser console
{name: "Bharat", birthdate: 1909, death: 1917}
{name: "baba", birthdate: 1950, death: 1972}
{name: "Tanish", birthdate: 2039, death: 2067}
{name: "rajesh", birthdate: 1845, death: 1875}
{name: "rahim", birthdate: 1989, death: 2049}