Text & Spans

Single-String Text

The simplest form — one string, block-level style:

container.Text("Hello, world!");

Chain style methods on the returned TextDescriptor to format the whole block:

container.Text("Section Heading")
    .Bold()
    .FontSize(16)
    .FontColor(Color.Blue.Darken2)
    .AlignCenter();

All `TextDescriptor` style methods

Method	Effect
`.Bold()`	Bold weight
`.SemiBold()`	Semi-bold (mapped to bold in the built-in font set)
`.Italic()`	Italic style
`.Strikethrough()`	Horizontal strikethrough line
`.Underline()`	Underline beneath the text
`.FontSize(double)`	Font size in PDF points
`.LineHeight(double)`	Line-height multiplier (e.g. `1.0` = tight, `1.4` = default, `2.0` = double-spaced)
`.FontColor(string)`	Hex colour, e.g. `"#1a4a8a"` or `Color.Red.Medium`
`.AlignLeft()`	Left-align (default)
`.AlignCenter()`	Centre-align
`.AlignRight()`	Right-align
`.Justify()`	Justify all lines except the last

Multi-Span Text

Use the Action<TextDescriptor> overload to compose a text block from multiple independently styled spans.

container.Text(t =>
{
    t.Span("Normal  ");
    t.Span("Bold  ").Bold();
    t.Span("Italic  ").Italic();
    t.Span("Struck  ").Strikethrough();
    t.Span("Coloured  ").FontColor(Color.Red.Medium);
    t.Span("Large").FontSize(16).FontColor("#1a4a8a");
});

Important: t.Span(...) returns a SpanDescriptor, not a TextDescriptor. Style methods chained after .Span() apply only to that span. This is intentional — it prevents accidental formatting of the whole block.

`SpanDescriptor` methods

Method	Effect
`.Bold()`	Bold weight for this span
`.SemiBold()`	Semi-bold for this span
`.Italic()`	Italic for this span
`.Strikethrough()`	Strikethrough for this span
`.Underline()`	Underline for this span
`.FontSize(double)`	Font size for this span
`.FontColor(string)`	Text colour for this span

Page Numbers

CurrentPageNumber() and TotalPages() also return SpanDescriptor so they can be individually styled:

page.Footer().AlignCenter().Text(t =>
{
    t.Span("Page ").FontSize(9).FontColor(Color.Grey.Medium);
    t.CurrentPageNumber().FontSize(9).FontColor(Color.Grey.Medium);
    t.Span(" of ").FontSize(9).FontColor(Color.Grey.Medium);
    t.TotalPages().FontSize(9).FontColor(Color.Grey.Medium);
});

Mixing Styles in One Block

Because the block's alignment is controlled at the TextDescriptor level, you can combine per-span colour/size with a block-level alignment:

container.Text(t =>
{
    t.Span("Status: ").Bold();
    t.Span("Approved").FontColor(Color.Green.Darken2).Bold();
    t.Span("  (June 2025)").FontColor(Color.Grey.Medium).FontSize(9);
})
.AlignRight();

Underline

.Underline() draws a line beneath the text. It works on both the whole block (TextDescriptor) and on individual spans (SpanDescriptor).

// Whole block underlined
container.Text("Important notice").Underline().Bold();

// Only one span underlined in a mixed block
container.Text(t =>
{
    t.Span("Visit ");
    t.Span("TerraPDF").Underline().FontColor(Color.Blue.Medium);
    t.Span(" for more info.");
});

// Underline and strikethrough can be combined
container.Text("Deprecated").Underline().Strikethrough().FontColor(Color.Grey.Medium);

Line Height

.LineHeight(double) sets a multiplier applied to the natural line height. The default multiplier is approximately 1.4.

container.Text("Tight paragraph.").LineHeight(1.0);
container.Text("Normal paragraph.").LineHeight(1.4);
container.Text("Relaxed paragraph.").LineHeight(1.6);
container.Text("Double-spaced paragraph.").LineHeight(2.0);

Line height can also be set page-wide via DefaultTextStyle:

page.DefaultTextStyle(s => s.FontSize(11).LineHeight(1.5));

Default Text Style

A page-wide default style is set on PageDescriptor and inherited by all text unless explicitly overridden at the block or span level:

page.DefaultTextStyle(s => s.FontSize(11).FontColor(Color.Grey.Darken2));

Style resolution order (highest wins):

Span style  >  Block style (TextDescriptor)  >  Page default style  >  Library default (12 pt, black)