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What are events in JavaScript? |
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Answer» If you want to check the type of an object at runtime, then use the instanceof operator. The RESULT is a boolean. Check for Array Let’s say we are checking if a VARIABLE is an array or not using instanceof operator. The syntax: variable_name instanceof ArrayThe following is our example and we are checking whether array exists or not: <html> <body> <script> var DEPARTMENT = [ "FINANCE", "Operations", "Marketing", "HR" ]; if (department instanceof Array) { alert('This is an Array!'); } else { alert('This is not an array!'); } </script> </body> </html>The output displays that array exists SINCE the if condition is true: Check for Object using instanceof To check for an object, use the instanceof operator, the following is the example: <html> <body> <script> var myObj = {}; if (myObj instanceof Object) { alert('This is an object!'); } else { alert('This is not an object!'); } </script> </body> </html>The output displays ‘this is an object!’ in an alert box, since the if condition is true:
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