JS: Object.isSealed

JS: Object.isSealed

By Xah Lee. Date: . Last updated: .

Object.isSealed(obj)

Return true if object obj is sealed, else false.

[see JS: Object.seal]

[see JS: Prevent Adding Property]

const x3 = {};
console.log(Object.isSealed(x3)); // false
Object.seal(x3);
console.log(Object.isSealed(x3)); // true

JS Object and Inheritance

  1. Object Overview
  2. Object Type
  3. Find Object's Type
  4. Prototype Chain
  5. Create Object
  6. Object Literal Expr
  7. Create Object with Parent X
  8. Get/Set Parent
  9. Show Prototype Chain
  10. Prevent Adding Property
  11. Clone Object
  12. Test Object Equality
  13. Add Method to Prototype
  14. Object Object
  15. Object.prototype
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Object and Inheritance

  1. Object Overview
  2. Object Type
  3. Find Object's Type
  4. Prototype Chain
  5. Create Object
  6. Object Literal Expr
  7. Create Object with Parent X
  8. Get/Set Parent
  9. Show Prototype Chain
  10. Prevent Adding Property
  11. Clone Object
  12. Test Object Equality
  13. Add Method to Prototype

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HTML Form

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DOM Misc

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jQuery

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