The Object.isFrozen() method checks if an object is frozen.
Example
isFrozen() syntax
The syntax of the isFrozen() method is:
Object.isFrozen(obj)
Here, isFrozen() is a static method. Hence, we need to access the method using the class name, Object.
Note: A frozen object can no longer be changed. Freezing an object prevents:
- New properties from being added to the object.
- Existing properties to be removed from the object.
- Changing the enumerability, configurability, or writability of existing properties.
- Changing values of the existing object properties and prototype.
isFrozen() Parameters
The isFrozen() method takes in:
- obj - the object which should be checked for being frozen or not.
isFrozen() Return Value
The isFrozen() method returns:
true- if the object is frozenfalse- if the object is not frozen
Example: Javascript Object.isFrozen()
In the above example, we tried to freeze newObj by
- using the
preventExtensions()method, and - making it unwritable by setting the
writableflag tofalse.
However, both approaches fail to freeze the object.
The final output indicates that newObj is frozen only after calling the freeze() method.
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