Paragraphs in Rich Text Documents
- 4 minutes to read
The Paragraph class represents paragraphs in the RichEditControl. You can manage them in code and using the User Interface.
Paragraphs in the User Interface
End-users can press Enter to divide text into paragraphs, and the Paragraph group on the Home ribbon tab allows them to format paragraphs. Refer to the How to: Create a Simple Word Processor with a Ribbon UI lesson for information on how to provide a ribbon UI for the RichEditControl.
End-users can specify advanced paragraph settings using the Paragraph Dialog. You can invoke this dialog from the ribbon group of from the context menu.
Tip
You can restrict end-users from formatting paragraphs or creating new paragraphs. Set the DXRichEditDocumentCapabilitiesOptions.Paragraphs, DXRichEditDocumentCapabilitiesOptions.ParagraphFormatting, or DXRichEditDocumentCapabilitiesOptions.ParagraphTabs property to Hidden or Disabled to disable or hide the corresponding commands in the Ribbon UI and the pop-up menu.
The RichEditControl can display, print and export to PDF format documents with paragraph borders.
The control does not provide user interface elements allowing end-users to create or modify paragraph borders.
Paragraphs in Code
Access Paragraphs
The Paragraph class represents paragraphs in the RichEditDocumentServer.
The ParagraphCollection contains all document paragraphs. Access a specific paragraph by its index using the SubDocument.Paragraphs property. The Section.Paragraphs property provides access to a collection of paragraphs in a particular document section. You can also retrieve the paragraph related to the given range using the ReadOnlyParagraphCollection.Get method.
Add New Paragraph
Use one of the following methods to insert new paragraph:
| Method | Description |
|---|---|
| ParagraphCollection.Append | Appends new paragraph. |
| ParagraphCollection.Insert | Inserts new paragraph at the specified document position. Returns a paragraph that follows the inserted paragraph. |
The code sample below appends a paragraph and inserts a paragraph at the start of the second section:
using DevExpress.XtraRichEdit.API.Native;
richEditControl.LoadDocument("FirstLook.docx");
Document document = richEditControl.Document;
document.BeginUpdate();
//Append paragraph:
Paragraph appendedParagraph = document.Paragraphs.Append();
document.InsertText(appendedParagraph.Range.Start, "Appended paragraph");
//Insert paragraph at the start of the second section:
Paragraph paragraph = document.Paragraphs.Insert(document.Sections[1].Range.Start);
document.InsertText(document.Paragraphs[paragraph.Index - 1].Range.Start,
"Inserted paragraph");
document.EndUpdate();
Format Paragraphs
Paragraphs can be formatted directly or using document styles. Refer to the Text Formatting topic for more examples on how to format paragraphs.
Note
The Rich Text Editor can load/save, print and export to PDF format documents with paragraph borders. There is no API to manage paragraph borders.
The code sample below shows how to change paragraph formatting in code:
using System.Windows;
using System.Drawing;
using DevExpress.XtraRichEdit;
using DevExpress.Office.Utils;
using DevExpress.XtraRichEdit.API.Native;
//...
Document doc = richEditControl1.Document;
DocumentRange range = doc.Selection;
ParagraphProperties pp = doc.BeginUpdateParagraphs(range);
// Center paragraph
pp.Alignment = ParagraphAlignment.Center;
// Set triple spacing
pp.LineSpacingType = ParagraphLineSpacing.Multiple;
pp.LineSpacingMultiplier = 3;
// Set left indent at 0.5".
// Default unit is 1/300 of an inch (a document unit).
pp.LeftIndent = Units.InchesToDocumentsF(0.5f);
// Set tab stop at 1.5"
TabInfoCollection tbiColl = pp.BeginUpdateTabs(true);
TabInfo tbi = new TabInfo();
tbi.Alignment = TabAlignmentType.Center;
tbi.Position = Units.InchesToDocumentsF(1.5f);
tbiColl.Add(tbi);
pp.EndUpdateTabs(tbiColl);
doc.EndUpdateParagraphs(pp);
Note
We recommend to format paragraphs using ParagraphProperties options instead of specifying the formatting options directly to the Paragraph object. Use the Paragraph object’s properties to check the information.
Remove Paragraphs
Call the SubDocument.Delete method and pass the paragraph range to remove it from the document.
The code sample below locates paragraphs at the end of the first section and removes them:
using DevExpress.XtraRichEdit.API.Native;
richEditControl.LoadDocument("FirstLook.docx");
Document document = richEditControl.Document;
document.BeginUpdate();
//Retrieve first section:
Section firstSection = document.Sections[0];
//Calculate the length of the last two paragraphs in section:
Paragraph lastParagraph = firstSection.Paragraphs.Last();
Paragraph secondLastParagraph = firstSection.Paragraphs[lastParagraph.Index - 1];
int length = secondLastParagraph.Range.Length + lastParagraph.Range.Length;
//Define a range to delete:
DocumentRange deleteRange =
document.CreateRange(secondLastParagraph.Range.Start, length);
//Clear the range:
document.Delete(deleteRange);
document.EndUpdate();