JavaScript Array.prototype.map() function

JavascriptWeb DevelopmentFront End TechnologyObject Oriented Programming

The Array.prototype.map() function of JavaScript is used create a new array with the results of called function.

The syntax is as follows −

arr.map(function callback(currentValue[, index[, array]])

Let us now implement the Array.prototype.map() method in JavaScript −

Example

 Live Demo

<!DOCTYPE html>
<html>
<body>
<h2>Demo Heading</h2>
<p>Click to display the abs() result...</p>
<button onclick="display()">Result</button>
<p id="test"></p>
<script>
   function display() {
      var arr = [1, -2, 3, 4, 5, -6, 7, 8, 9, 10];
      var res = arr.map(Math.abs);
      document.write(res);
   }
</script>
</body>
</html>

Output

Click the “Result” button above −

Example

 Live Demo

<!DOCTYPE html>
<html>
<body>
<h2>Demo Heading</h2>
<p>Click to round the numbers...</p>
<button onclick="display()">Result</button>
<p id="test"></p>
<script>
   var arr = [11.4, 12.9, 25.6, 88.9];
   document.getElementById("test").innerHTML = arr
   function display() {
      var res = arr.map(Math.round);
      document.getElementById("test").innerHTML = res
   }
</script>
</body>
</html>

Output

Click the “Result” button to round the numbers −

raja
Published on 17-Dec-2019 09:39:14
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