catch Archives | JS FAQ - JavaScript Guides Online

How to throw errors inside a promise in JavaScript

Best practices for promise rejection handling include attaching .catch() handlers, avoiding try/catch for async errors, centralizing error handling with a single catch in chains, meaningful error logging, proper async/await try/catch usage, and implementing global unhandled rejection handlers in Node.js and browsers.

Fetch API and AJAX

How to handle fetch errors in JavaScript

Fetch API and AJAXcatch, error, fetch, js fetch

Implementing retry logic enhances application resilience against unreliable networks and transient errors. Wrapping fetch calls in retry functions allows multiple attempts before failing. Strategies like exponential backoff and fallback mechanisms improve user experience by managing request failures effectively.

Error Handling

How to rethrow an error in JavaScript

Error Handlingcatch, js errors, throw again, try

Rethrowing errors while preserving the original stack trace is crucial for effective debugging. Using the Error constructor and techniques like attaching original errors or using Object.setPrototypeOf can maintain context. Methods like Error.captureStackTrace offer precise stack trace management, enhancing error handling in applications.

Promises and Async-Await

How to catch promise errors using catch in JavaScript

Promises and Async-Awaitcatch, error handling, js promises, promise

Best practices for promise error handling include placing catch at the end of promise chains for centralized error management, avoiding multiple catch blocks unless necessary, not mixing callback-style error handling with catch, and carefully using Promise.all with individual error handling to prevent silent failures or unhandled rejections.

Error Handling

How to catch and log errors in JavaScript

Error Handlingcatch, console.log, js errors, try

Effective error logging involves capturing error messages, stack traces, and contextual information like user IDs and request paths. Structured logging with severity levels, global error handlers, sampling strategies, and integration with monitoring services improves error tracking, prioritization, and application resilience.

Error Handling

How to handle errors in JavaScript using try and catch

Error Handlingcatch, error, js errors, try

Parsing error.message in JavaScript is a fragile anti-pattern. For robust error handling, use custom error classes extending Error. Check error types in a catch block with instanceof for NetworkError or ValidationError. A type-safe, stable alternative to string inspection.