The JavaScript Reflect.isExtensible() method determines if an object is extensible or not. It is similar to Object.isExtensible().
Syntax:
Reflect.isExtensible(obj)
Parameters:
target: It represents the object which to check if it is extensible.
Return: It returns true if the object is extensible otherwise returns false.
Note: It throws TypeError, if the target is not an Object.
Reflect.isExtensible() VS Object.isExtensible()
Reflect.isExtensible(31); // It throws TypeError: 31 is not an object Object.isExtensible(31); // It returns false
Example 1:
<!DOCTYPE html> <html> <body> <script> const obj = {prop:100}; document.write(Reflect.isExtensible(obj)); </script> </body> </html>
Example 2:
<!DOCTYPE html> <html> <body> <script> const object1 = {}; document.write(Reflect.isExtensible(object1)); document.write("</br>"); Reflect.preventExtensions(object1); document.write(Reflect.isExtensible(object1)); document.write("</br>"); const object2 = Object.seal({}); document.write(Reflect.isExtensible(object2)); </script> </body> </html>