Paragraphs in Rich Text Documents
- 6 minutes to read
Paragraphs in the User Interface
Users can press Enter to divide text into paragraphs. The Paragraph group on the Home ribbon tab allows you to format paragraphs. Refer to the How to: Create the RichEditControl with a Ribbon UI lesson for information on how to create a RichEditControl application with a Ribbon UI.
Use the Paragraph Dialog to specify advanced paragraph settings. You can invoke this dialog from the ribbon group or from the context menu.
Tip
You can restrict users from formatting paragraphs or creating new paragraphs. Set the DocumentCapabilitiesOptions.Paragraphs, ParagraphFormatting, or ParagraphTabs property to DocumentCapability.Hidden or DocumentCapability.Disabled to disable or hide the corresponding commands in the command UI and the pop-up menu.
The RichEditControl can display, print, and export to PDF format documents with paragraph borders.
Note
The control does not ship with the User Interface elements to create or modify paragraph borders.
Paragraphs in Code
Obtain Paragraphs
The ParagraphCollection holds all document paragraphs. Access specific paragraphs by their index with the SubDocument.Paragraphs property. The Section.Paragraphs property allows you to retrieve paragraphs within a specific document section. Alternatively, retrieve paragraphs for a specified range by the Paragraphs.Get method call.
The code snippet retrieves the paragraph related to the specified position and appends text to the end of this paragraph:
using DevExpress.XtraRichEdit.API.Native;
Document document = richEditControl.Document;
document.BeginUpdate();
// Append text to the document (multiple paragraphs).
document.AppendText("First Paragraph\nSecond Paragraph\nThird Paragraph");
document.EndUpdate();
// Access the end position of the document range.
DocumentPosition position = document.Range.End;
// Append text to the end of the last paragraph.
SubDocument doc = position.BeginUpdateDocument();
Paragraph par = doc.Paragraphs.Get(position);
DocumentPosition newPos = doc.CreatePosition(par.Range.End.ToInt() - 1);
doc.InsertText(newPos, "<<Appended to Paragraph End>>");
pos.EndUpdateDocument(doc);
Add New Paragraph
To insert a new paragraph, use one of these methods:
| Method | Description |
|---|---|
| ParagraphCollection.Append | Appends a new paragraph. |
| ParagraphCollection.Insert | Inserts a new paragraph at the specified document position and returns the paragraph that follows the inserted paragraph. |
The following code snippet 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 a paragraph:
Paragraph appendedParagraph = document.Paragraphs.Append();
document.InsertText(appendedParagraph.Range.Start, "Appended paragraph");
// Insert a new 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
Format paragraphs directly or apply document styles. For more examples on formatting paragraphs, refer to this topic: Text Formatting
The following snippet changes paragraph formatting in code:
using DevExpress.XtraRichEdit.API.Native;
using DevExpress.Office.Utils;
document.BeginUpdate();
document.AppendText("Modified Paragraph\nNormal\nNormal");
document.EndUpdate();
// Obtain the first paragraph range
DocumentRange range = document.Paragraphs[0].Range;
// Obtain paragraph options
ParagraphProperties pp = document.BeginUpdateParagraphs(range);
// Center a 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 a 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);
//Finalize the update
document.EndUpdateParagraphs(pp);
Set Paragraph Borders
Obtain border settings for a specific range through the ParagraphProperties.Borders property.
The Paragraph.Borders property allows you to specify borders for an individual paragraph. Call the ParagraphBorders.Reset() method to reset borders.
The following code snippet sets borders for multiple paragraphs:
using DevExpress.XtraRichEdit;
using DevExpress.XtraRichEdit.API.Native;
using System.Drawing;
Document document = richEditControl.Document;
// Start to edit the document.
document.BeginUpdate();
// Append text to the document.
document.AppendText(String.Format("Modified Paragraph" +
Environment.NewLine + "Normal" + Environment.NewLine + "Normal"));
// Finalize the edit operation.
document.EndUpdate();
// Obtain a range from the first to the last paragraph
Paragraph firstParagraph = document.Paragraphs[0];
Paragraph thirdParagraph = document.Paragraphs[2];
DocumentRange paragraphRange =
document.CreateRange(firstParagraph.Range.Start, thirdParagraph.Range.End.ToInt() - firstParagraph.Range.Start.ToInt());
// Start to edit the paragraph.
ParagraphProperties pp = document.BeginUpdateParagraphs(paragraphRange);
SetBorder(pp.Borders.HorizontalBorder);
SetBorder(pp.Borders.BottomBorder);
SetBorder(pp.Borders.TopBorder);
SetBorder(pp.Borders.LeftBorder);
SetBorder(pp.Borders.RightBorder);
// Finalize the edit operation.
document.EndUpdateParagraphs(pp);
static void SetBorder(ParagraphBorder border)
{
border.LineWidth = 2f;
border.LineStyle = BorderLineStyle.Thick;
border.LineColor = Color.SteelBlue;
}
Remove Paragraphs
Call the SubDocument.Delete method and pass the paragraph range as the method parameter to remove the paragraph from the document.
The following code snippet locates and removes paragraphs at the end of the first section:
using DevExpress.XtraRichEdit.API.Native;
using System.Linq;
richEditControl.LoadDocument("FirstLook.docx");
Document document = richEditControl.Document;
document.BeginUpdate();
// Retrieve the first section:
Section firstSection = document.Sections[0];
// Calculate the length of the last two paragraphs:
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();