Question

How to seal an object to prevents adding new properties to the object in JavaScript

Answer 1

const obj = {
  name: 'Dan'
}

Object.seal(obj);

obj.name = 'Tom';
obj.id = 72374;

document.write(obj.name + "<br />");
document.write(obj.id + "<br />");



/*
run:
      
Tom
undefined
    
*/

 

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