Blog : JavaScript For...In Statement

JavaScript For...In Statement


JavaScript For...In Statement

The for...in statement loops through the elements of an array or through the properties of an object.

Syntax

for (variable in object)
  {
  code to be executed
  }

Note: The code in the body of the for...in loop is executed once for each element/property.

Note: The variable argument can be a named variable, an array element, or a property of an object.

Example

Use the for...in statement to loop through an array:

Example

<html>
<body>

<script type="text/javascript">
var x;
var mycars = new Array();
mycars[0] = "Saab";
mycars[1] = "Volvo";
mycars[2] = "BMW";

for (x in mycars)
  {
  document.write(mycars[x] + "<br />");
  }
</script>

</body>
</html>