PDF Page Count Count PDF pages.

The tool works by using the `pdf-lib` library to parse uploaded PDF files and extract page count information. When a file is dropped into the FileDropzone component, the `handleFile` function is triggered, which sets the file state and initializes the processing of the PDF document. The `PDFDocument.load` method from `pdf-lib` is used to load the PDF file into memory, with the `ignoreEncryption` option set to true to handle encrypted files. The page count is then retrieved using the `getPageCount` method and stored in the component's state.

The tool uses memoized functions, such as `handleFile` and `process`, to optimize performance and prevent unnecessary re-renders. The `process` function is responsible for extracting detailed information about each page, including its size in points, which is calculated using the `getSize` method of the `PDFPage` object. The results are then formatted into a string and stored in the component's state, where they can be displayed to the user or downloaded as a text file. The tool's responsive UI is built using React and CSS, with components like the FileDropzone and glass-card providing a visually appealing and interactive interface for users.

When the user clicks the "Count Pages" button, the `process` function is executed, which uses the `arrayBuffer` method to read the contents of the uploaded file and then loads it into a `PDFDocument` object using `pdf-lib`. The page count and sizes are then extracted and formatted into a string, which is displayed to the user. If an error occurs during processing, an error message is displayed instead. The tool also uses the `URL.createObjectURL` method to create a downloadable link for the results, allowing users to save the page count information as a text file.

The `download` function is responsible for creating a blob from the result string and then using the `URL.createObjectURL` method to generate a downloadable link. The `reset` function is used to clear the component's state and reset the UI to its initial state, allowing users to upload a new file and start the process again. Overall, the tool provides a convenient and efficient way for users to extract page count information from PDF files, using a combination of client-side JavaScript, React, and `pdf-lib` to provide a fast and accurate solution.