Text Search and Selection

In the Flutter SDK, ComPDF provides the CPDFTextSearcher API to search for specific text in PDF documents, highlight results, and retrieve contextual text snippets.

Get a CPDFTextSearcher Instance

To perform a search, obtain a CPDFTextSearcher object from the CPDFDocument:

late CPDFReaderWidgetController _controller;

Scaffold(
  resizeToAvoidBottomInset: false,
  body: CPDFReaderWidget(
    document: widget.documentPath,
    configuration: CPDFConfiguration(),
    onCreated: (controller) {
      setState(() {
        _controller = controller;
      });
    },
  ));


CPDFTextSearcher? textSearcher = _controller?.document.getTextSearcher();

Text Search

Use the searchText method to search for keywords in the PDF document. You can specify search options such as case sensitivity or whole-word matching.

// Search for keywords in the PDF document
List<CPDFTextRange> results = await searcher.searchText(
  'keywords',
  searchOptions: CPDFSearchOptions.caseInsensitive, // Search option
);

The search results are returned as a list of CPDFTextRange objects, each representing the position of the keyword in the document.

Explanation of Search Settings

Enum Value	Description
CPDFSearchOptions.caseInsensitive	Case-insensitive search (default)
CPDFSearchOptions.caseSensitive	Case sensitive search
CPDFSearchOptions.matchWholeWord	Matches a whole word only

Select a Search Result

You can highlight a specific result in the document using the selection method:

// Select the first search result
if (results.isNotEmpty) {
  CPDFTextRange range = results[0];
  await searcher.selection(range);
}

Clear Search Results

To reset the search state and clear results:

await searcher.clearSearch();

Retrieve Contextual Text

With CPDFPage.getText, you can extract a snippet of text for a given range and optionally expand the range to include surrounding context.

// Assume we already have a search result
CPDFTextRange range = results[0];

// Expand the range to include 20 characters before and after
final expandedRange = range.expanded(before: 20, after: 20);

// Retrieve contextual text from the corresponding page
final contextText = await page.getText(expandedRange);
print("Text with context: $contextText");