How to Zoom Word Document using Spire.DocViewer

Zoom is a basic as well useful function in any text file reader. Users can chose to zoom out or zoom in of a document depending on how small the font is, or on their own view preference. In this article, I’ll introduce two ways to zoom Word file using Spire.DocViewer:

• Zoom with a particular zoom mode
• Zoom by entering a percentage

Now, I will explain more by creating a Windows Forms Application. Some steps about how to add DocVierwer control to toolbox and how to open Word file using Spire.DocViewer have been demonstrated previously. In the following section, I only add a MenuItem and a TextBox to Form1.

In the MenuItem, named Zoom, I create three sub-items which are used to save three particular zoom modes.

• Default: View page in its original size.
• Fit to page: When this option is selected, the document will be resized to match the dimensions of your view window.
• Fit to width: When this option is selected, the document will best fit to width of window.

Code behind:

        private void defaultToolStripMenuItem_Click(object sender, EventArgs e)
        {
            this.docDocumentViewer1.ZoomMode = ZoomMode.Default;
        }
        private void fitToPageToolStripMenuItem_Click(object sender, EventArgs e)
        {
            this.docDocumentViewer1.ZoomMode = ZoomMode.FitPage;
        }
        private void fitToWidthToolStripMenuItem_Click(object sender, EventArgs e)
        {
            this.docDocumentViewer1.ZoomMode = ZoomMode.FitWidth;
        }

Another way to zoom in or out of Word document is enter a desired percentage in TextBox.

Code for TextBox:

      private void toolStripTextBox1_KeyDown(object sender, KeyEventArgs e)
        {
            if (Keys.Enter == e.KeyCode)
            {
                int p;
                if (int.TryParse(this.toolStripTextBox1.Text, out p))
                {
                    this.docDocumentViewer1.ZoomTo(p);
                }
            }
        }

Run the program, you can get following windows application.

Fit to Width:

Zoom with 50 percentages: