Note: Add a reference in your project to PDFresizeNET To do this:   a. On the Project menu, click Add Reference;   b. On the .NET tab, locate PDFresizeNET and then click Select;   c. Click OK in the Add References dialog box to accept your selections.

  PDFresize.Neevia NVresize = new PDFresize.Neevia();
  int retVal;

  NVresize.PageWidth = 5; // page width = 5 inches
  NVresize.PageHeight = 10; // page height = 10 inches
  NVresize.Units = 1; // measurement units = inches

  NVresize.Scale = true; // scale page
  NVresize.ConstrainProportions = true; // constrain proportions when scaling

  NVresize.Center = true; // center page content

  NVresize.Linearize = true; // linearize output file

  retVal = NVresize.resizePDF(@"c:\in.pdf",@"c:\out.pdf");

  if (retVal != 0) {
     MessageBox.Show("Error code = " + retVal.ToString());
  } else {
     MessageBox.Show("Done");
  }