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 End-User Documentation


This document consists of the following sections.

Expanded Zooming In and Out of a Document

Use buttons from the Zoom button group of the PDF Viewer tab.

To zoom in a document, click the Zoom In button on the toolbar, or press the Ctrl+Plus sign.

To zoom out of a document, click the Zoom Out button on the toolbar, or press the Ctrl+Minus sign.

To zoom in or out of a document, you can also hold down Ctrl and rotate the mouse wheel.

Expanded Using Marquee Zoom Tool

The Marquee Zoom tool allows end users to zoom in a particular part of the page.

To activate the Marquee Zoom tool:

You can perform the following actions:

  • zoom in on a portion of a page by dragging a rectangle around it;

  • increase the zoom level by clicking;
  • decrease the zoom level by clicking while pressing the Ctrl key.

Expanded Using a Specific Zoom Factor

To zoom to a specific zoom factor, click the Zoom dropdown list button. The following list will be invoked.

Choose the percentage value of the zoom factor or one of the following zoom factor presets.

  • Actual Size

    Sets the document zoom factor value to 100%.

  • Zoom to Page Level

    Sets the document zoom factor value to fit the entire page height.

  • Fit Width

    Sets the document zoom factor value to fit the entire page width.

  • Fit Visible

    The document zoom factor is calculated to fit the actual content of a page (if possible).

To specify zoom mode in code, set the PdfViewer.ZoomMode property to one of the PdfZoomMode enumeration values. When the PdfViewer.ZoomMode property is set to PdfZoomMode.Custom mode, you can specify a document zoom factor value using the PdfViewer.ZoomFactor property. To obtain minimum and maximum allowed zoom factors, use the PdfViewer.MinZoomFactor and PdfViewer.MaxZoomFactor properties.

To perform specific actions after a document's zoom is changed, handle the PdfViewer.ZoomChanged event.

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