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JAVASCRIPT / CHAPTER 06

JavaScript
Storage.

Storing data: JSON vs object, parse and shape guards, window.labStorage, a list and CRUD with stable ids, corrupt data with explicit recovery, failed writes, and an expense app. Learn and Practice; challenges are separate.

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JavaScript

11 lessons available

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The foundations behind your ideas.

1. 01

   JSON vs Object · Locked

   JSON is text, an object is a value

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2. 02

   Stringify & Parse · Locked

   JSON round-trip

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3. 03

   Nested JSON · Locked

   array of objects with nested arrays

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4. 04

   Invalid JSON · Locked

   try/catch around JSON.parse

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5. 05

   Shape Guard · Locked

   valid JSON, wrong shape

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6. 06

   labStorage Basics · Locked

   getItem, setItem, removeItem, null vs ""

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7. 07

   Save a List · Locked

   array as JSON under one key

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8. 08

   CRUD Records · Locked

   stable ids, edit, delete

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9. 09

   Corrupt & Recover · Locked

   load error is not an empty store

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10. 10

    Write Failure · Locked

    QuotaExceededError and an honest status

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11. 11

    Expense App · Locked

    save and restore a list

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