About page text extraction

[kuyeduwu]

Thank you for this great work, but it seems some of the types / methods have been implemented, like TEXTPAGE object, I didn't find any implementation of the method to get the page text.

Not sure if I missed something or if those functions are still developing.

Also, I found this is really helpful to my project, but the last commit is about 1 year ago, is this still actively maintained?

[ArgusMagnus]

You are right, there are many functions which are not wrapped yet.

I'm sorry to say that it is not activity maintained, I'm tied up with work and other projects. I would welcome collaborators though.

[kuyeduwu]

Ok, maybe I could wrap some of them with my project going. It's not easy to find a good open source C# PDF library, I wish I could make some contributions to keep it going. :)

[Morcatko]

I would like to help as well, although I don't have much free time, Anyway for start here is short snippet to get text from a page with bounding rects

using (var pdfDocument = new PdfDocument(pdfFile))
{
	var page = pdfDocument.Pages[0];
	var textPage = PDFium.FPDFText_LoadPage(page.Handle);
	var rectCount = PDFium.FPDFText_CountRects(textPage, 0, 1000000);
	for (int i = 0; i < rectCount; i++)
	{
		PDFium.FPDFText_GetRect(textPage, i, out var l, out var t, out var r, out var b);
		var text = PDFium.FPDFText_GetBoundedText(textPage, l, t, r, b);
		Console.WriteLine($"{(int)l}, {(int)t}, {(int)r}, {(int)b} - {text}");
	}
}

It is a prototype so no unloading/releasing handles and it is probably missing some rotated pages handling

[kuyeduwu]

@Morcatko thank you for this snippet. And @ArgusMagnus do you have any preferences on code standard or something like that on this project?

[bradleypeet]

I might be able to help you out. I spent the better part of this weekend coding up a "PdfText" class to support text extraction (with a painful level of granularity should you need it). I guess when I have time and feel like the code is solid enough I can do a fork and maybe even a pull request. New to Github so still learning the ropes here.

[bradleypeet]

Attached are two files: the PdfText class I created and a modified FS_RECTF.cs file that it requires. You'll need to add/modify the following code in PdfPage.cs to hook the Text property up and ensure it gets disposed. Keep in mind this is a work in-progress, not thoroughly tested. If anything is missing/unresolved, let me know.

public PdfText Text
{   
    get
    {
        if (_text == null)
        {
            _text = PdfText.Load(this);
        }
        return _text;
    }
}
private PdfText _text;
protected override void Dispose(FPDF_PAGE handle)
{            
    (_text as IDisposable)?.Dispose();
    PDFium.FPDF_ClosePage(handle);
}

PdfText.cs.txt FS_RECTF.cs.txt