Welcome to the lesson on writing to files in PHP. As a programmer, the ability to save data to a file is essential for tasks such as logging information, saving user data, and generating reports. This lesson focuses on the fundamentals of writing text to files using PHP's file_put_contents() function, an important skill for managing data in real-world applications. By the end of this lesson, you'll be equipped with the knowledge to write and append content to files using PHP.

To begin writing to a file in PHP, we'll use the file_put_contents() function. Let's explore how this is done step by step:

1. Specify the Output File Path: Begin by defining the file path where your data will be stored.

2. Write Data to the File: Using the file_put_contents() function, write the desired content to the file. This function takes the file path and the content to write as arguments.

When executed, this sequence of operations will create a file named output.txt (if it doesn't already exist), write the specified lines of text into it, and the content will overwrite any existing content if the file exists.

The content of the file after executing file_put_contents() will look like this:

Sometimes you may want to add data to an existing file without overwriting its current contents. This is easily achieved in PHP using file_put_contents() with the FILE_APPEND flag. The FILE_APPEND flag tells the file_put_contents() function to add new content to the end of an existing file.

When the append operation completes, the new line is added to the end of the existing file content. Following this operation, the final content of the file will be:

We've covered the fundamental skills necessary for writing and appending text to files using PHP's file_put_contents() function. You've learned how to use file_put_contents() to write data and how to append new content to existing files using the FILE_APPEND flag. These techniques are critical in many software development scenarios, such as logging and data persistence.

In the upcoming practice exercises, you'll get the chance to consolidate your understanding by applying these techniques in different contexts. Congratulations on making it to the end of this lesson! You’re now equipped to handle text data manipulation tasks in PHP with confidence.