如何有效地從 JavaScript 物件中刪除 Null 或未定義的屬性？

// Return a new object without blank attributes
let o = Object.fromEntries(Object.entries(obj).filter(([_, v]) => v != null));

// Mutate the object in place (not recommended)
Object.keys(obj).forEach((k) => obj[k] == null && delete obj[k]);

// Return a new object with blanks removed
let o = Object.keys(obj)
  .filter((k) => obj[k] != null)
  .reduce((a, k) => ({ ...a, [k]: obj[k] }), {});

// Mutate the object in place (not recommended)
Object.keys(obj)
  .filter((k) => obj[k] != null)
  .forEach((k) => delete obj[k]);