在WP8.1上生成PDF不能换行

Question

我在vb.Net中找到了一个将文本生成为PDF的代码，我试图在C＃中将其翻译，并且可以正常工作如何在VB或C＃中的Windows Phone上生成PDF，但是文本的问题很长，就像一个段落，所以它将不要输入下一行，它将显示一行，而在pdf上仅显示6或7个字，这就是它的显示方式

对于代码是：

    private async void EditButton_Click(object sender, RoutedEventArgs e)
    {


         listitem = (e.OriginalSource as MenuFlyoutItem).DataContext as WritePadFileContent;
         //MessageDialog messageDialog = new MessageDialog(listitem.Name.ToString());
         //await messageDialog.ShowAsync(); 

        var file = await ApplicationData.Current.LocalFolder.CreateFileAsync(listitem.Name.ToString()+".pdf", CreationCollisionOption.GenerateUniqueName);
        using (Stream stream = await WindowsRuntimeStorageExtensions.OpenStreamForWriteAsync(file))
        {
            var writer = new StreamWriter(stream, Encoding.UTF8);
            List<long> xrefs = new List<long>();
            // PDF-HEADER
            writer.WriteLine("%PDF-1.2");
            // PDF-BODY. Convention is to start with a 4-byte binary comment
            // so everyone recognizes the pdf as binary. Then the file has
            // a load of numbered objects, #1..#7 in this case
            writer.Write("%"); writer.Flush();
            byte[] vbbyte = new byte[4] { 0, 0, 0, 0 };
            stream.Write(vbbyte, 0, 4);
            stream.Flush();
            writer.WriteLine("");
            // #1; catalog - the overall container of the entire PDF
            writer.Flush();
            stream.Flush();
            xrefs.Add(stream.Position);
            writer.WriteLine("1 0 obj");
            writer.WriteLine("<<");
            writer.WriteLine("  /Type /Catalog");
            writer.WriteLine("  /Pages 2 0 R");
            writer.WriteLine(">>");
            writer.WriteLine("endobj");
            // #2; page-list - we have only one child page
            writer.Flush(); stream.Flush(); xrefs.Add(stream.Position);
            writer.WriteLine("2 0 obj");
            writer.WriteLine("<<");
            writer.WriteLine("  /Type /Pages");
            writer.WriteLine("  /Kids [3 0 R]");
            writer.WriteLine("  /Count 1");
            writer.WriteLine(">>");
            writer.WriteLine("endobj");
            // #3; page - this is our page. We specify size, font resources, and the contents
            writer.Flush(); stream.Flush(); xrefs.Add(stream.Position);
            writer.WriteLine("3 0 obj");
            writer.WriteLine("<<");
            writer.WriteLine("  /Type /Page");
            writer.WriteLine("  /Parent 2 0 R");
            writer.WriteLine("  /MediaBox [0 0 612 792]"); // Default userspace units; 72/inch, origin at bottom left
            writer.WriteLine("  /Resources");
            writer.WriteLine("<<");
            writer.WriteLine("    /ProcSet [/PDF/Text]"); // This PDF uses only the Text ability
            writer.WriteLine("    /Font");
            writer.WriteLine("<<");
            writer.WriteLine("      /F0 4 0 R"); // I will define three fonts, #4, #5 and #6
            writer.WriteLine("      /F1 5 0 R");
            writer.WriteLine("      /F2 6 0 R");
            writer.WriteLine("    >>");
            writer.WriteLine("  >>");
            writer.WriteLine("  /Contents 7 0 R");
            writer.WriteLine(">>");
            writer.WriteLine("endobj");
            // #4, #5, #6; three font resources, all using fonts that are built into all PDF-viewers
            // We//re going to use WinAnsi character encoding, defined below.
            writer.Flush(); stream.Flush(); xrefs.Add(stream.Position);
            writer.WriteLine("4 0 obj");
            writer.WriteLine("<<");
            writer.WriteLine("  /Type /Font");
            writer.WriteLine("  /Subtype /Type1");
            writer.WriteLine("  /Encoding /WinAnsiEncoding");
            writer.WriteLine("  /BaseFont /Times-Roman");
            writer.WriteLine(">>");
            writer.Flush(); stream.Flush(); xrefs.Add(stream.Position);
            writer.WriteLine("5 0 obj");
            writer.WriteLine("<<");
            writer.WriteLine("  /Type /Font");
            writer.WriteLine("  /Subtype /Type1");
            writer.WriteLine("  /Encoding /WinAnsiEncoding");
            writer.WriteLine("  /BaseFont /Times-Bold");
            writer.WriteLine(">>");
            writer.Flush(); stream.Flush(); xrefs.Add(stream.Position);
            writer.WriteLine("6 0 obj");
            writer.WriteLine("<<");
            writer.WriteLine("  /Type /Font");
            writer.WriteLine("  /Subtype /Type1");
            writer.WriteLine("  /Encoding /WinAnsiEncoding");
            writer.WriteLine("  /BaseFont /Times-Italic");
            writer.WriteLine(">>");
            // #7; contents of page. This is written in postscript, fully described in
            // chapter 8 of the PDF 1.2 reference manual.
            writer.Flush(); stream.Flush(); xrefs.Add(stream.Position);
            var sb = new StringBuilder();
            sb.AppendLine("BT");  // BT = begin text object, with text-units the same as userspace-units
            sb.AppendLine("/F0 40 Tf");  // Tf = start using the named font "F0" with size "40"
            sb.AppendLine("40 TL"); // TL = set line height to "40"
            sb.AppendLine("230.0 400.0 Td");// Td = position text point at coordinates "230.0", "400.0"
            sb.AppendLine("(Hello all)"); // Apostrophe = print the text, and advance to the next line
            sb.AppendLine("/F2 20 Tf");//
            sb.AppendLine("20 TL");//
            sb.AppendLine("0.0 0.2 1.0 rg");// rg = set fill color to RGB("0.0", "0.2", "1.0")
            //sb.AppendLine("(olaaaa" + "é" + ") '");
            //sb.AppendLine("(olaaaa" + "é" + ") '");
            sb.AppendLine("(" + listitem.Description.ToString() + ") '");

            sb.AppendLine("ET"); //
            writer.WriteLine("7 0 obj");
            writer.WriteLine("<<");
            writer.WriteLine("  /Length " + sb.Length);
            writer.WriteLine(">>");
            writer.WriteLine("stream");

            writer.Write(sb.ToString());

            writer.WriteLine("endstream");

            writer.WriteLine("endobj"); ;



            // PDF-XREFS. This part of the PDF is an index table into every object #1..#7

            // that we defined.

            writer.Flush(); stream.Flush(); var xref_pos = stream.Position;

            writer.WriteLine("xref");

            writer.WriteLine("1 " + xrefs.Count);

            foreach (object xref in xrefs)
            {

                writer.WriteLine("{0:0000000000} {1:00000} n", xref, 0);

            }



            // PDF-TRAILER. Every PDF ends with this trailer.

            writer.WriteLine("trailer");

            writer.WriteLine("<<");

            writer.WriteLine("  /Size " + xrefs.Count);

            writer.WriteLine("  /Root 1 0 R");

            writer.WriteLine(">>");

            writer.WriteLine("startxref");

            writer.WriteLine(xref_pos);

            writer.WriteLine("%%EOF");

            writer.Flush(); stream.Flush();

        }





        await Launcher.LaunchFileAsync(file);
    }

因此，如果有其他代码可以帮助我使用Windows Phone 8.1 C＃或其他示例。 此代码添加pdf文件的名称

var file = await ApplicationData.Current.LocalFolder.CreateFileAsync(listitem.Name.ToString()+".pdf", CreationCollisionOption.GenerateUniqueName);

此代码给我在pdf中添加说明

sb.AppendLine("(" + listitem.Description.ToString() + ") '");

Answer 1

对于最后的代码，我感到很困惑，因为它是用后记写的，因此无法使用，因为我找不到与第8章相关的PDF 1.2参考手册。

但是我尝试使用另一个库，并且它可以与WP8.1 C＃Xfinium一起使用，这是一个简单的库，因此您最多下载Xfinium库，这是代码的屏幕截图（第二个按钮）

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Runtime.InteropServices.WindowsRuntime;
using System.Text;
using Windows.Foundation;
using Windows.Foundation.Collections;
using Windows.Storage;
using Windows.System;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using Windows.UI.Xaml.Controls.Primitives;
using Windows.UI.Xaml.Data;
using Windows.UI.Xaml.Input;
using Windows.UI.Xaml.Media;
using Windows.UI.Xaml.Navigation;
using Xfinium.Pdf;
using Xfinium.Pdf.Actions;
using Xfinium.Pdf.Core;
using Xfinium.Pdf.Graphics;
using Xfinium.Pdf.Graphics.FormattedContent;

// The Blank Page item template is documented at http://go.microsoft.com/fwlink/?LinkId=391641

namespace App40
{
    /// <summary>
    /// An empty page that can be used on its own or navigated to within a Frame.
    /// </summary>
    public sealed partial class MainPage : Page
    {
        public MainPage()
        {
            this.InitializeComponent();

            this.NavigationCacheMode = NavigationCacheMode.Required;
        }

        /// <summary>
        /// Invoked when this page is about to be displayed in a Frame.
        /// </summary>
        /// <param name="e">Event data that describes how this page was reached.
        /// This parameter is typically used to configure the page.</param>
        protected override void OnNavigatedTo(NavigationEventArgs e)
        {
            // TODO: Prepare page for display here.

            // TODO: If your application contains multiple pages, ensure that you are
            // handling the hardware Back button by registering for the
            // Windows.Phone.UI.Input.HardwareButtons.BackPressed event.
            // If you are using the NavigationHelper provided by some templates,
            // this event is handled for you.
        }

        private  void Button_Click(object sender, RoutedEventArgs e)
        {
        }


        //this is a tutrila can help you with simple text
        private async void Button_Click1(object sender, RoutedEventArgs e)
        {

            var file = await ApplicationData.Current.LocalFolder.CreateFileAsync("a.pdf", CreationCollisionOption.ReplaceExisting);
            using (Stream stream = await WindowsRuntimeStorageExtensions.OpenStreamForWriteAsync(file))
            {
                PdfFixedDocument document = new PdfFixedDocument();
                PdfPage page = document.Pages.Add();
                // Create a standard font with Helvetica face and 24 point size
                PdfStandardFont helvetica = new PdfStandardFont(PdfStandardFontFace.Helvetica, 24);
                // Create a solid RGB red brush.
                PdfBrush brush = new PdfBrush(PdfRgbColor.Red);
                // Draw the text on the page.
                string cha = "title";
                page.Graphics.DrawString(cha, helvetica, brush, 250, 50);
                // Draw the text on the page. max tableau 50
                string ch = "azj aeiajiahfioe foiehfioehfiehfie feifjaepfjaepofjaepo fpaejfpeafjaefaefhevpzevje vjepzvihzev zep";
                page.Graphics.DrawString(ch, helvetica, brush, 10, 100);

                document.Save(stream);


            }
            await Launcher.LaunchFileAsync(file);

            //FileStream input = File.OpenRead("optionalcontent-src.pdf");
            //PdfFile file = new PdfFile(input);

        }

        //this is a tutrila can help you with paragraph block
        private async void Button_Click2(object sender, RoutedEventArgs e)
        {
            var file = await ApplicationData.Current.LocalFolder.CreateFileAsync("a.pdf", CreationCollisionOption.ReplaceExisting);
            using (Stream stream = await WindowsRuntimeStorageExtensions.OpenStreamForWriteAsync(file))
            {
                string paragraph2Block1Text = "The development style is based on fixed document model, where each page is created as needed " +
                "and content is placed at fixed position using a grid based layout.\r\n" +
                "This gives you access to all PDF features, whether you want to create a simple file " +
                "or you want to create a transparency knockout group at COS level, and lets you build more complex models on top of the library.";

                PdfStandardFont textFont = new PdfStandardFont(PdfStandardFontFace.TimesRoman, 12);

                PdfFormattedParagraph paragraph2 = new PdfFormattedParagraph();
                paragraph2.SpacingAfter = 3;
                paragraph2.FirstLineIndent = 10;
                paragraph2.HorizontalAlign = PdfStringHorizontalAlign.Justified;
                paragraph2.LineSpacingMode = PdfFormattedParagraphLineSpacing.Multiple;
                paragraph2.LineSpacing = 1.2;
                paragraph2.Blocks.Add(new PdfFormattedTextBlock(paragraph2Block1Text, textFont));

                PdfFormattedContent formattedContent = new PdfFormattedContent();
                formattedContent.Paragraphs.Add(paragraph2);

                PdfFixedDocument document = new PdfFixedDocument();
                PdfPage page = document.Pages.Add();

                page.Graphics.DrawFormattedContent(formattedContent, 50, 50, 500, 700);
                page.Graphics.CompressAndClose();

                document.Save(stream);
            }
            await Launcher.LaunchFileAsync(file);
        }
    }
}