Apex Lists

Introduction to Apex Lists

Apex Lists are a fundamental data structure used in Salesforce development, providing an ordered collection of elements. Lists are dynamic, meaning their size can change at runtime, making them an essential tool for handling collections of data, particularly SObjects.

Creating and Initializing Lists

To use a list in Apex, you must define its type, which can be any primitive, user-defined, or system-defined Apex type. The syntax follows the pattern List<T>, where T is the data type of the list elements.

Adding Elements to a List

Elements can be added to a list using the add() method. You can add elements individually or multiple elements at once.

Accessing List Elements

List elements can be accessed by their index, with the first element at index 0. You can retrieve, update, or remove elements using their index.

Iterating Over Lists

Apex provides various ways to iterate over lists, including traditional for loops and enhanced for loops. These loops allow you to process each element in a list.

Common List Methods

Apex Lists come with several built-in methods that facilitate common operations like sorting, checking for containment, and clearing all elements.

Conclusion

Apex Lists are versatile and powerful for managing collections of data in Salesforce. Understanding how to manipulate lists is crucial for efficient Apex programming.