问如何从Web应用程序打印？

EN

using System;
using System.Data;
using System.Web;
using System.Collections;
using System.Web.Services;
using System.Web.Services.Protocols;
using System.Text;
using iTextSharp;
using iTextSharp.text;
using iTextSharp.text.pdf;

namespace iTextFormFillerDemo
{
    [WebService(Namespace = "http://tempuri.org/")]
    [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
    public class DemoForm : IHttpHandler
    {

        public void ProcessRequest(HttpContext context)
        {

            context.Response.ContentType = "application/pdf";
            //This line will force the user to either open or save the 
            //file instead of it appearing on its own page - if you remove it, 
            //the page will appear in the browser in the same window.
            context.Response.AddHeader("Content-Disposition", 
                "attachment; filename=DemoForm_Filled.pdf");

            FillForm(context.Response.OutputStream);

            context.Response.End();
        }

        // Fills the form and pushes it out the output stream.
        private void FillForm(System.IO.Stream outputStream)
        {
            //Need to get the proper directory (dynamic path) for this file. 
            //This is a filesystem reference, not a web/URL reference...
            //The PDF reader reads in the fillable form
            PdfReader reader = new PdfReader("C:/DemoForm_Fillable.pdf");

            //The PDF stamper creates an editable working copy of the form from the reader 
            //and associates it with the response output stream
            PdfStamper stamper = new PdfStamper(reader, outputStream);

            //The PDF has a single "form" consisting of AcroFields
            //Note that this is shorthand for writing out 
            //stamper.AcroFields.SetField(...) for each set
            AcroFields form = stamper.AcroFields;

            //Set each of the text fields this way: SetField(name, value)
            form.SetField("txtFieldName", "Field Value");
            form.SetField("txtAnotherFieldName", "AnotherField Value");

            //Set the radio button fields using the names and string values:
            form.SetField("rbRadioButtons", "Yes"); //or "No"

            //Form flattening makes the form non-editable and saveable with the 
            //form data filled in
            stamper.FormFlattening = true;

            //Closing the stamper flushes it out the output stream
            stamper.Close();

            //We're done reading the file
            reader.Close();
        }

        public bool IsReusable
        {
            get
            {
                return false;
            }
        }
    }
}