Step 6

Let's implement a method to "update" a note given its ID:

update(id, content, author) {
  const index = this.notes.findIndex((note) => note._id === id);
  if (index !== -1) {
    this.notes[index].content = content;
    this.notes[index].author = author;
    return this.notes[index];
  }
  return null;
}

Let's also provide an operation to "delete" a note given its ID:

delete(id) {
  const index = this.notes.findIndex((note) => note._id === id);
  if (index !== -1) {
    const note = this.notes[index];
    this.notes.splice(index, 1);
    return note;
  }
  return null;
}

To test our application, update the index.js where we created sample notes previously to update/delete notes given their id:

const notes = new NoteDao();
notes.create("Sample 1", "Author 1");
notes.create("Sample 2", "Author 2");
notes.create("Sample 3", "Author 2");
notes.create("Sample 4", "Author 1");
console.log(notes.read(2));
console.log(notes.readAll("Author 1"));
console.log(notes.readAll());
console.log(notes.update(0, "Sample 0", "Author 3"));
console.log(notes.delete(1));
console.log(notes.readAll());

As you save the changes to your file, you must see the sample notes printed to the terminal.

Expected output

Note { content: 'Sample 3', author: 'Author 2', _id: 2 }
[
  Note { content: 'Sample 1', author: 'Author 1', _id: 0 },
  Note { content: 'Sample 4', author: 'Author 1', _id: 3 }
]
[
  Note { content: 'Sample 1', author: 'Author 1', _id: 0 },
  Note { content: 'Sample 2', author: 'Author 2', _id: 1 },
  Note { content: 'Sample 3', author: 'Author 2', _id: 2 },
  Note { content: 'Sample 4', author: 'Author 1', _id: 3 }
]
Note { content: 'Sample 0', author: 'Author 3', _id: 0 }
Note { content: 'Sample 2', author: 'Author 2', _id: 1 }
[
  Note { content: 'Sample 0', author: 'Author 3', _id: 0 },
  Note { content: 'Sample 3', author: 'Author 2', _id: 2 },
  Note { content: 'Sample 4', author: 'Author 1', _id: 3 }
]

Now that we know the NoteDao works fine, delete all the console.log message in index.js and leave it as creating four sample notes.

CS280 Notes

Step 6