Coming from Xceed DocX

DocX loads a Word document with DocX.Load, exposes Paragraphs, Tables, InsertParagraph, ReplaceText and AddTable, and saves. OneDocument's Document covers the same ground on the lossless model, and adds templating, conversion and rendering. Read README.md first for what is true on every page.

Load, read, add, save

// Xceed DocX
using var doc = DocX.Load(path);
foreach (Paragraph p in doc.Paragraphs) { Console.WriteLine(p.Text); }
doc.InsertParagraph("Added");
doc.SaveAs(outPath);

// OneDocument
using Document doc = Document.Open(path);
foreach (Paragraph p in doc.Paragraphs) { Console.WriteLine(p.Text); }
doc.Body.AddParagraph("Added");
doc.SaveAs(outPath);

Document.Create() makes a new document. Save() replaces the opened file atomically. Document.Open also reads .doc, .rtf, .odt and Word 2003 XML, which DocX does not.

Styles on paragraphs

// Xceed DocX
paragraph.StyleName = "Heading1";

// OneDocument
paragraph.Style = "Heading 1";                       // by name; an unknown name throws, nothing is created
doc.Body.AddParagraph("Title").Style = "Heading 1";

Style definitions, inheritance and numbering are resolved by the hub (docs/docx-styles-numbering.md).

Replace text

// Xceed DocX
doc.ReplaceText("[name]", "Ada");

// OneDocument: find and replace across runs, keeping formatting
doc.Replace("[name]", "Ada");

The exact call shape, the search options (case, whole word, regular expression) and the report it returns are in docs/operations-find-replace.md. For filling placeholders use the template engine below, which is tolerant of tags that Word split across runs.

Templates and mail merge

// Xceed DocX: placeholders replaced one by one
doc.ReplaceText("{{customer}}", customer.Name);

// OneDocument: tags, loops and conditions in the document, data from an object, JSON, a dictionary or a DataTable
Template.Render(path, invoice, outPath);          // outPath may be .docx or .pdf

Syntax: {{ customer.name }}, {% for line in lines %} ... {% endfor %}, {% if overdue %}; expressions are Excel formulas (docs/templating.md, docs/templating-docx.md). Word's own merge fields are filled by doc.MailMerge(data) (docs/mail-merge.md).

Tables

// Xceed DocX
Table t = doc.AddTable(2, 3);
t.Rows[0].Cells[0].Paragraphs[0].Append("A1");
doc.InsertTable(t);

// OneDocument
Table t = doc.Body.AddTable(2, 3);                 // or AddTable(rows) from strings
t.SetCellText(0, 0, "A1");
t.InsertRow(1);

AddTable adds the table at the end of the body in the Table Grid style, at the page's text width. Existing tables are fully editable (rows, columns, merged cells through the logical cell model).

Images, headers, footers, properties

Pictures: paragraph.AddPicture(bytes, widthPoints, heightPoints, altText) (or body.AddPicture) adds an inline picture; the template engine inserts pictures too ({% image %}), and existing pictures are kept and rendered. Links: paragraph.AddHyperlink("text", "https://..."). Headers and footers: doc.Sections[0] exposes them (docs/docx-tables-sections.md). Core properties (Title, Creator, ...) are on the document's properties object (docs/docx-stories-properties.md).

Output formats

doc.SaveAs("x.pdf"), "x.rtf", "x.odt", "x.html", "x.md" pick the writer by extension. Conversions that lose something report it (doc.ImportLoss for what was lost reading, doc.ExportLoss for writing RTF; docs/rtf.md, docs/html.md).

Not supported or different

• No fluent chaining of formatting (Bold().Color(...) on appended text). Formatting is set through properties of the run returned by paragraph.AddRun("text"): run.Bold = true; run.Color = "C00000";.
• No AddHeaders helper on the hub; headers and footers are reached through doc.Sections.
• No DocX.Create + InsertParagraph of formatted text in one call; the paragraph is added, then its runs are added and formatted.
• Revisions are a full model (doc.Revisions: read, author, accept, reject), which DocX does not have.