Open and save PDF file in Flutter PDF

10 Oct 20221 minute to read

Opening an existing PDF document

You can open an existing PDF document by using the PdfDocument class. The following example shows how to load an existing document from the list of bytes.

DART

//Opens an existing document from the list of bytes
PdfDocument document =
    PdfDocument(inputBytes: File('input.pdf').readAsBytesSync());

Opening an existing PDF document from the base 64 string

You can open an existing document from the base 64 string by using the PdfDocument class as shown below.

DART

//Opens an existing document from the base 64 string
PdfDocument document = PdfDocument.fromBase64String(
    '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');

Saving a PDF document to list of bytes

You can save the manipulated PDF document as a list of bytes using the save method of PdfDocument class. Also, you can save the list of bytes to the file system as follows.

DART

//Opens an existing PDF document
PdfDocument document =
    PdfDocument(inputBytes: File('input.pdf').readAsBytesSync());

//Saves the document into a list of bytes
List<int> bytes =await document.save();

//Saves the bytes to the file system
File('output.pdf').writeAsBytes(bytes);