🔰error handling

JS ⟩ async ⟩ Promise ⟩ error handling

⭐️ 重點

• .catch() callback is for：

  • reporting errors

  • handling errors

  • recovering from errors

• .catch() callback can throw a new error, but if it returns normally, than that return value is used to resolve (fulfill) the associated Promise, and the error stops propagating.

🔴 主題

• recoverable errors

• finally()

💈範例

⬆️ require： getJSON()

// use second callback parameter to handle errors.
getJSON("/api/user/profile")
    .then(doThisIfFulfilled, doThisIfRejected);

// use .catch() (more idiomatic way)
getJSON("/api/user/profile")
    .then(displayUserProfile)
    .catch(profileError);

Untitled

• JS.info ⟩ error handling with Promises

📘 手冊

• Promise ⟩ .catch()

👥 相關

• getJSON()

• await ⟩ error handling