Text Selection

PdfViewer supports text selection through the UI and also programmatically.

To select text from the UI, the Mode property of RadPdfViewer should be set to TextSelection. Read more about the available modes in the Viewer Modes article.

TextSelection is part of the RadPdfProcessing library which is used for the document model of the PdfViewer.

Setting the mode of RadPdfViewer

this.pdfViewer.Mode = FixedDocumentViewerMode.TextSelection; 

The programmatic selection is part of the RadFixedDocument API (the Document property value of RadPdfViewer). To access it, use its Selection property of the document. It gives access to a TextSelection object that provides a set of properties and methods that can be used to select text.

The TextSelection class introduces the StartPosition and EndPosition properties that can be used to access the selection range. Read more about the position objects in the Text Position article.

Accessing the current selection positions

TextPosition selectionStart = this.pdfViewer.Document.Selection.StartPosition; 
TextPosition selectionEnd = this.pdfViewer.Document.Selection.EndPosition; 

The set the selection, use one of the methods of TextSelection.

When setting the selection programmatically, the UI will display the selection visual even if the mode of PdfViewer is not set to TextSelection.

• SetSelectionStart

• SetSelectionEnd

  Setting selection using SetSelectionStart and Set SelectionEnd methods

      RadFixedPage page = this.pdfViewer.Document.Pages[0]; 
      TextPosition start = new TextPosition(page, 100);             
      TextPosition end = new TextPosition(page, 200); 
      this.pdfViewer.Document.Selection.SetSelectionStart(start); 
      this.pdfViewer.Document.Selection.SetSelectionEnd(end); 
  

• SetSelection

  Setting selection using SetSelection method

      RadFixedPage page = this.pdfViewer.Document.Pages[0]; 
      TextPosition start = new TextPosition(page, 100);             
      TextPosition end = new TextPosition(page, 200); 
      this.pdfViewer.Document.Selection.SetSelection(start, end); 
  

• SelectAll

  Selecting all text

      this.pdfViewer.Document.Selection.SelectAll(); 
  

• Clear

  Clearing the text selection

      this.pdfViewer.Document.Selection.Clear(); 
  

  To get the selected text, you can use the GetSelectedText method of TextSelection.

Getting the selected text

    string text = this.pdfViewer.Document.Selection.GetSelectedText(); 

Events

TextSelection provides two events that can be used to listen for changes in the position - SelectionChanging and SelectionChanged.

Subscribe to selection changing events

void SubscribeToEvents() 
{ 
    this.pdfViewer.Document.Selection.SelectionChanging += Selection_SelectionChanging; 
    this.pdfViewer.Document.Selection.SelectionChanged += Selection_SelectionChanged; 
} 
 
private void Selection_SelectionChanging(object sender, EventArgs e) 
{        
} 
 
private void Selection_SelectionChanged(object sender, EventArgs e) 
{ 
} 

See Also

• Text Position
• Scrolling
• Interaction Modes
• ToolBar