Introduction

Vue.js provides a way to handle errors at the global level using `Vue.config.errorHandler`. This is useful for catching and logging errors that occur within Vue components or during component lifecycle events. In this guide, we'll explore how to set up and use global error handling with `Vue.config.errorHandler` and provide sample code to demonstrate the process.

Sample Code

Let's create a Vue.js application that showcases global error handling using `Vue.config.errorHandler`:

<div id="app">
  <button @click="causeError">Cause Error</button>
const app = new Vue({
  el: '#app',
  methods: {
    causeError() {
      // Simulate an error by accessing an undefined variable
      try {
        // Access an undefined variable to cause an error
        const result = undefinedVariable.value;
      } catch (error) {
        // Handle the error
        this.handleError(error);
      }
    },
    handleError(error) {
      // Global error handling using Vue.config.errorHandler
      Vue.config.errorHandler = (err, vm, info) => {
        console.error('Global Error Handler:', err);
        console.error('Vue Component:', vm);
        console.error('Info:', info);
      };
      // Trigger the error handler
      throw error;
    }
  }
});
            

In this code:

• We create a Vue component with a button that, when clicked, calls the `causeError` method to simulate an error by accessing an undefined variable.
• Inside the `causeError` method, we use a `try...catch` block to handle the error and call the `handleError` method to pass the error for global handling.
• The `handleError` method sets up the global error handler using `Vue.config.errorHandler`. It logs the error, the Vue component, and additional information when an error occurs.
• We intentionally trigger the error handler by throwing the error, which leads to the global error handling code being executed.