Office Open
PPTX

Patching

Modify existing .pptx files by replacing placeholders with new content

Patch an existing .pptx template by replacing {{placeholder}} tokens with new text runs.

patchPresentation

Replaces placeholders in an existing .pptx file:

import { patchPresentation, PatchType, TextRun, Presentation, Packer } from "@office-open/pptx";
import { writeFileSync } from "node:fs";

// Create a template with placeholders
const templatePres = new Presentation({
  title: "Patch Demo",
  slides: [
    {
      children: [
        {
          shape: {
            x: 80,
            y: 120,
            width: 720,
            height: 80,
            textBody: {
              children: [{ children: [{ text: "Hello {{name}}!" }] }],
            },
          },
        },
      ],
    },
  ],
});

const templateBuffer = await Packer.toBuffer(templatePres);

// Patch the template
const result = await patchPresentation({
  outputType: "nodebuffer",
  data: templateBuffer,
  patches: {
    name: {
      type: PatchType.PARAGRAPH,
      children: [new TextRun({ text: "World", bold: true, fontSize: 24 })],
    },
  },
});

writeFileSync("output.pptx", result);

PatchType

TypeDescription
PatchType.PARAGRAPHReplace the placeholder with inline run-level content

The patch replaces placeholder text inside a paragraph with new runs. The original run's formatting properties (font, size, color, bold, etc.) are preserved by default.

patches: {
  title: {
    type: PatchType.PARAGRAPH,
    children: [
      new TextRun({ text: "Hello ", bold: true }),
      new TextRun("World"),
    ],
  },
}

Custom Delimiters

Default delimiters are {{ and }}. Change them with placeholderDelimiters:

await patchPresentation({
  outputType: "nodebuffer",
  data: templateBuffer,
  patches: { name: { type: PatchType.PARAGRAPH, children: [new TextRun("John")] } },
  placeholderDelimiters: { start: "<<", end: ">>" },
});

Options

OptionTypeDefaultDescription
outputTypestring—Output format (see Export page)
dataBuffer | Uint8Array | ...—Input .pptx file data
patchesRecord<string, IPatch>—Map of placeholder name to patch content
keepOriginalStylesbooleantruePreserve original run formatting properties
placeholderDelimiters{ start: string, end: string}{ {{, }} }Custom placeholder delimiters

Tips

  • Placeholders span across split runs in PowerPoint — the library handles this automatically.
  • keepOriginalStyles defaults to true, preserving the template's run formatting (font, size, color, etc.).
  • All slides are processed — the same placeholder on multiple slides will be replaced everywhere.
  • Image media files in ppt/media/ can be replaced by including data (Uint8Array) in the patch.

Parsing

Parse existing .pptx files with parsePresentation and parsePptx

@office-open/xlsx

Generate .xlsx spreadsheets with a declarative TypeScript API

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