使用列和添加元素

Question

我使用iTextSharp中的MultiColumnText對象創建pdf。文本進入第二頁，只填充左欄。所以我有兩個問題：

1）是否有可能填寫第二頁上的所有三列，只佔用盡可能多的垂直空間，因爲它需要？

2）是否可以在列對象結束後添加其他頁面元素而不將新元素敲入新頁面？

Answer 1

這是我的解決方案，在最後一頁中將文本平均分散在3列中。

訣竅是 1）模擬代碼 2）找到 3哪一列代碼結束）查找文本多遠下來的頁面去 4）計算新的「底部」 5）只適用新的「底部」到非模擬輸出的最後一頁

class Program 
{ 
    static void Main(string[] args) 
    { 
     string fileName = "columntexttest.pdf"; 

     Document doc = new Document(PageSize.LETTER, 50, 50, 50, 50); 
     PdfWriter pdfWrite = PdfWriter.GetInstance(doc, new FileStream(fileName, FileMode.Create)); 
     doc.Open(); 

     PdfContentByte cb = pdfWrite.DirectContent; 
     ColumnText ct = new ColumnText(cb); 

     //default values 
     int colCount = 0; 
     float bottom = doc.Bottom; 
     int pageCount = 0; 


     AddText(ct); 
     CreateColumnText(doc, ct, ref bottom, true, ref pageCount, ref colCount); //simulation 
     AddText(ct); 
     CreateColumnText(doc, ct, ref bottom, false, ref pageCount, ref colCount); //non-simulation 
     doc.Add(new Paragraph("testing new paragraph")); 

     doc.Close(); 
     System.Diagnostics.Process.Start(fileName); 
    } 


    private static void CreateColumnText(Document doc, ColumnText ct, ref float bottom, bool simulate, ref int pageCount, ref int colCount) 
    { 
     //reseting variables for non-simulation 
     int status = 0; 
     int currentPage = 1; 
     int currentColumn = 0; 
     float tempBottom = bottom; 
     float tempBottom2 = tempBottom; 
     if (simulate) 
     { 
      pageCount = 1; 
     } 

     //column attributes 
     float gutter = 15f; 
     float colwidth = (doc.Right - doc.Left - gutter * 2)/3; 


     while (ColumnText.HasMoreText(status)) 
     { 
      //calculates the bottom Y 
      if (simulate == false && currentPage == pageCount) 
      { 
       if (colCount == 1) //1 column on final page 
       { 
        tempBottom2 = (doc.Top - tempBottom)/3 + 6; 
        bottom = doc.Top - tempBottom2; 
       } 
       else if (colCount == 2) //2 columns on final page 
       { 
        tempBottom2 = ((doc.Top - tempBottom) + doc.Top)/3 + 6; 
        bottom = doc.Top - tempBottom2; 
       } 
       else if (colCount == 0) //0 colCount means 3 columns 
       { 
        tempBottom2 = ((doc.Top - tempBottom) + doc.Top * 2)/3 + 6; 
        bottom = doc.Top - tempBottom2; 
       } 
      } 
      else 
      { 
       bottom = doc.Bottom; //default value for all pages except the last, or the value for a single page 
      } 

      if (currentColumn == 0) //writes first column 
      { 
       float[] left = {doc.Left, doc.Top, //top = 742 (true top is 792 then a 50 point margin) 
          doc.Left, bottom }; //bottom = 50 

       float[] right = {doc.Left + colwidth, doc.Top, 
          doc.Left + colwidth, bottom}; 

       ct.SetColumns(left, right); 
       currentColumn++; 
      } 
      else if (currentColumn == 1) //writes second column 
      { 
       float[] left2 = {doc.Left+ colwidth + gutter, doc.Top, 
          doc.Left + colwidth + gutter, bottom}; 

       float[] right2 = {doc.Right - colwidth - gutter, doc.Top, 
          doc.Right - colwidth - gutter, bottom}; 

       ct.SetColumns(left2, right2); 
       currentColumn++; 
      } 

      else //writes third column 
      { 
       float[] left3 = { doc.Right - colwidth, doc.Top, 
          doc.Right- colwidth, bottom}; 

       float[] right3 = { doc.Right, doc.Top, 
          doc.Right, bottom}; 

       ct.SetColumns(left3, right3); 
       currentColumn = 0; 
      } 

      status = ct.Go(simulate); //simulate mode 

      if (currentColumn == 0 && status == 2) //creates new page only if text remains. 
      { 
       doc.NewPage(); 
       currentPage += 1; 
      } 
     } 

     //values carry forward to non-simulation mode 
     pageCount = currentPage; 
     bottom = ct.YLine; 
     colCount = currentColumn; 
    } 

    private static void AddText(ColumnText ct) 
    { 
     Font font2 = new Font(Font.NORMAL, 9f); 
     ct.AddText(new Phrase("orem ipsum dolor sit amet, consectetuer adipiscing elit. Suspendisse blandit blandit turpis. Nam in lectus ut dolor consectetuer bibendum. Morbi neque ipsum, laoreet id; dignissim et, viverra id, mauris. Nulla mauris elit, consectetuer sit amet, accumsan eget, congue ac, libero. Vivamus suscipit. Nunc dignissim consectetuer lectus. Fusce elit nisi; commodo non, facilisis quis, hendrerit eu, dolor? Suspendisse eleifend nisi ut magna. Phasellus id lectus! Vivamus laoreet enim et dolor. Integer arcu mauris, ultricies vel, porta quis, venenatis at, libero. Donec nibh est, adipiscing et, ullamcorper vitae, placerat at, diam. Integer ac turpis vel ligula rutrum auctor! Morbi egestas erat sit amet diam. Ut ut ipsum? Aliquam non sem. Nulla risus eros, mollis quis, blandit ut; luctus eget, urna. Vestibulum vestibulum dapibus erat. Proin egestas leo a metus?\n\n", font2)); 
     ct.AddText(new Phrase("Vivamus enim nisi, mollis in, sodales vel, convallis a, augue? Proin non enim. Nullam elementum euismod erat. Aliquam malesuada eleifend quam! Nulla facilisi. Aenean ut turpis ac est tempor malesuada. Maecenas scelerisque orci sit amet augue laoreet tempus. Duis interdum est ut eros. Fusce dictum dignissim elit. Morbi at dolor. Fusce magna. Nulla tellus turpis, mattis ut, eleifend a, adipiscing vitae, mauris. Pellentesque mattis lobortis mi.\n\n", font2)); 
     ct.AddText(new Phrase("Nullam sit amet metus scelerisque diam hendrerit porttitor. Aenean pellentesque, lorem a consectetuer consectetuer, nunc metus hendrerit quam, mattis ultrices lorem tellus lacinia massa. Aliquam sit amet odio. Proin mauris. Integer dictum quam a quam accumsan lacinia. Pellentesque pulvinar feugiat eros. Suspendisse rhoncus. Sed consectetuer leo eu nisi. Suspendisse massa! Sed suscipit lacus sit amet elit! Aliquam sollicitudin condimentum turpis. Nunc ut augue! Maecenas eu eros. Morbi in urna consectetuer ipsum vehicula tristique.\n\n", font2)); 
     ct.AddText(new Phrase("Donec imperdiet purus vel ligula. Vestibulum tempor, odio ut scelerisque eleifend, nulla sapien laoreet dui; vel aliquam arcu libero eu ante. Curabitur rutrum tristique mi. Sed lobortis iaculis arcu. Suspendisse mauris. Aliquam metus lacus, elementum quis, mollis non, consequat nec, tortor.\n", font2)); 
     ct.AddText(new Phrase("Quisque id diam. Ut egestas leo a elit. Nulla in metus. Aliquam iaculis turpis non augue. Donec a nunc? Phasellus eu eros. Nam luctus. Duis eu mi. Ut mollis. Nulla facilisi. Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Class aptent taciti sociosqu ad litora torquent per conubia nostra, per inceptos himenaeos. Aenean pede. Nulla facilisi. Vestibulum mattis adipiscing nulla. Praesent orci ante, mattis in, cursus eget, posuere sed, mauris.\n\n", font2)); 
     ct.AddText(new Phrase("Nulla facilisi. Nunc accumsan risus aliquet quam. Nam pellentesque! Aenean porttitor. Aenean congue ullamcorper velit. Phasellus suscipit placerat tellus. Vivamus diam odio, tempus quis, suscipit a, dictum eu; lectus. Sed vel nisl. Ut interdum urna eu nibh. Praesent vehicula, orci id venenatis ultrices, mauris urna mollis lacus, et blandit odio magna at enim. Pellentesque lorem felis, ultrices quis, gravida sed, pharetra vitae, quam. Mauris libero ipsum, pharetra a, faucibus aliquet, pellentesque in, mauris. Cras magna neque, interdum vel, varius nec; vulputate at, erat. Quisque vitae urna. Suspendisse potenti. Nulla luctus purus at turpis! Vestibulum vitae dui. Nullam odio.\n\n", font2)); 
     ct.AddText(new Phrase("Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Sed eget mi at sem iaculis hendrerit. Nulla facilisi. Etiam sed elit. In viverra dapibus sapien. Aliquam nisi justo, ornare non, ultricies vitae, aliquam sit amet, risus! Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Phasellus risus. Vestibulum pretium augue non mi. Sed magna. In hac habitasse platea dictumst. Quisque massa. Etiam viverra diam pharetra ante. Phasellus fringilla velit ut odio! Nam nec nulla.\n\n", font2)); 
     ct.AddText(new Phrase("Integer augue. Morbi orci. Sed quis nibh. Nullam ac magna id leo faucibus ornare. Vestibulum eget lectus sit amet nunc facilisis bibendum. Donec adipiscing convallis mi. Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Vivamus enim. Mauris ligula lorem, pellentesque quis, semper sed, tristique sit amet, justo. Suspendisse potenti. Proin vitae enim. Morbi et nisi sit amet sapien ve.", font2)); 

     ct.Alignment = Element.ALIGN_JUSTIFIED; 
    } 

} 

Answer 2

我能想到的唯一的事情就是使用go（true）來將您的文本「寫出」到ColumnText中，以模擬佈局並找出您的文本的真正高度（沒有分頁符），並使用它知識來構建具有特定高度的列，以使它們變得均勻。

如果你的列不是全部相同的寬度，這會變得非常困難。

當計算您需要處理多少空間時，請不要忘記頁面頂部的邊距&。