Object.isSealed()

Why Object.isSealed ?

First of all, Sealing an object means that existing features are not deleted or new features are added. Object.isSealed () is used to check if the object is sealed (If you do not know Object.seal (), click on the link and learn the topic first).

Object.isSealed () takes the object as an argument to be checked and returns a boolean representing whether the object is sealed or not. Returns true if the object is sealed, otherwise false. If an object is not extensible and all properties cannot be configured and therefore cannot be removed , it is sealed.

Object.seal () is used to seal an object. Next, Object.freeze () is used to freeze (similar to sealing). It is also possible to seal an object using Object.defineProperty () to forward it to Object.preventExtensions () and then delete all of its properties.

Syntax:

Object.isSealed( obj )

obj: The object to be checked.

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JavaScript Object.isSealed Example

        let myObj = {
            prop1: "true",
            prop2: "codes",
            prop3: ".org"
        };

        
        let control1 = Object.isSealed(myObj);
        console.log(control1)

        Object.seal(myObj);
        let control2 = Object.isSealed(myObj);
        console.log(control2)

output:

false
true

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Sources:

• https://www.geeksforgeeks.org
• https://www.oreilly.com

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Browser Support

Chrome	6
Edge	yes
Firefox	4
Internet Explorer	9
Opera	12
Safari	5.1
Android webview	yes
Chrome for Android	yes
Edge mobile	yes
Firefox for Android	4
Opera Android	yes