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Converting HTML to images allows you to transform HTML content into static images that can be easily shared on social media, embedded in emails, or used as thumbnails in search engine results. This conversion process ensures that your content is displayed consistently across different devices and browsers, improving the overall user experience. In this article, you will learn how to convert HTML to images in React using Spire.Doc for JavaScript.
Install Spire.Doc for JavaScript
To get started with converting Word documents to PDF in a React application, you can either download Spire.Doc for JavaScript from our website or install it via npm with the following command:
npm i spire.office
The downloaded product package integrates Spire.Doc for JavaScript, Spire.XLS for JavaScript, Spire.PDF for JavaScript, and Spire.Presentation for JavaScript. To use the features of Spire.Doc for JavaScript, you need to copy the corresponding files (spire.doc.js, Spire.Doc.Wasm.zip, spire.common.js, Spire.Common.Wasm.zip, and the _framework folder) to the public folder of your project. To ensure proper text rendering, you can add relevant font files with a custom path. In the following example, the font is added to the path: public\static\font.
For more details, refer to the documentation: How to Integrate Spire.Doc for JavaScript in a React Project
Convert an HTML File to an Image in JavaScript
Spire.Doc for JavaScript allows you to load an HTML file and convert a specific page to an image stream using the Document.SaveImageToStreams() method. The image streams can then be further saved to a desired image format such as jpg, png, bmp, gif. The following are the main steps.
- Load the font file to ensure correct text rendering.
- Create a new document using the new wasmModule.Document() method.
- Load the HTML file using the Document.LoadFromFile() method.
- Convert a specific page to an image stream using the Document.SaveImageToStreams() method.
- Save the image stream to a specified image format.
- JavaScript
import React, { useState, useEffect } from 'react';
function App() {
const [wasmModule, setWasmModule] = useState(null);
// Load Spire.Doc
useEffect(() => {
(async () => {
try {
const publicUrl = process.env.PUBLIC_URL || '';
const spireModule = await import(/* webpackIgnore: true */ `${publicUrl}/spire.doc.js`);
const rawModule = spireModule.default || spireModule;
window.wasmModule = typeof rawModule === 'function'
? await rawModule({ locateFile: p => p.endsWith('.wasm') ? `${publicUrl}/${p}` : p })
: rawModule;
setWasmModule(window.wasmModule);
} catch (error) {
console.error('Failed to load spire.doc.js WASM module:', error);
}
})();
}, []);
// Function to convert an HTML file to an image
const HtmlToImage = async () => {
const wasmModule = window.wasmModule.spiredoc;
if (wasmModule) {
// Load the font files into the virtual file system (VFS)
await window.spire.FetchFileToVFS('CALIBRI.ttf', '/Library/Fonts/', `${process.env.PUBLIC_URL}/static/font/`);
// Specify the input file name
const inputFileName = 'sample.html';
// Fetch the input file and add it to the VFS
await window.spire.FetchFileToVFS(inputFileName, '', `${process.env.PUBLIC_URL}/static/data/`);
// Create an instance of the Document class
const doc = new wasmModule.Document();
// Load the HTML file
doc.LoadFromFile({ fileName: inputFileName, fileFormat: wasmModule.FileFormat.Html, validationType: wasmModule.XHTMLValidationType.None });
// Save the first page as an image stream
let image = doc.SaveImageToStreams({ pageIndex: 0, type: wasmModule.ImageType.Bitmap });
// Save the image stream as a PNG file
const outputFileName = 'HtmlToImage.png';
image.Save(outputFileName);
// Read the generated image from VFS
const modifiedFileArray = window.dotnetRuntime.Module.FS.readFile(outputFileName);
// Create a Blog object from the image file
const modifiedFile = new Blob([modifiedFileArray], { type: 'image/png' });
// Create a URL for the Blob
const url = URL.createObjectURL(modifiedFile);
// Create an anchor element to trigger the download
const a = document.createElement("a");
a.href = url;
a.download = outputFileName;
document.body.appendChild(a);
a.click();
document.body.removeChild(a);
URL.revokeObjectURL(url);
// Clean up resources
doc.Dispose();
}
};
return (
<div style={{ textAlign: 'center', height: '300px' }}>
<h1>Convert an HTML File to an Image Using JavaScript in React</h1>
<button onClick={HtmlToImage} disabled={!wasmModule}>
Convert
</button>
</div>
);
}
export default App;
Run the code to launch the React app at localhost:3000. Once it's running, click on the "Convert" button to download the image converted from an HTML file:

Below is the converted image file:

Convert an HTML String to an Image in JavaScript
To convert HTML strings to images, you'll need to first add HTML strings to the paragraphs of a Word page through the Paragraph.AppendHTML() method, and then convert the page to an image. The following are the main steps.
- Load the font file to ensure correct text rendering.
- Specify the HTML string.
- Create a new document using the new wasmModule.Document() method.
- Add a new section using the Document.AddSection() method.
- Add a paragraph to the section using the Section.AddParagraph() method.
- Append the HTML string to the paragraph using the Paragraph.AppendHTML() method.
- Convert a specific page to an image stream using the Document.SaveImageToStreams() method.
- Save the image stream to a specified image format.
- JavaScript
import React, { useState, useEffect } from 'react';
function App() {
const [wasmModule, setWasmModule] = useState(null);
// Load Spire.Doc
useEffect(() => {
(async () => {
try {
const publicUrl = process.env.PUBLIC_URL || '';
const spireModule = await import(/* webpackIgnore: true */ `${publicUrl}/spire.doc.js`);
const rawModule = spireModule.default || spireModule;
window.wasmModule = typeof rawModule === 'function'
? await rawModule({ locateFile: p => p.endsWith('.wasm') ? `${publicUrl}/${p}` : p })
: rawModule;
setWasmModule(window.wasmModule);
} catch (error) {
console.error('Failed to load spire.doc.js WASM module:', error);
}
})();
}, []);
// Function to convert an HTML string to an image
const HtmlStringToImage = async () => {
const wasmModule = window.wasmModule.spiredoc;
if (wasmModule) {
// Load the font files into the virtual file system (VFS)
await window.spire.FetchFileToVFS('CALIBRI.ttf', '/Library/Fonts/', `${process.env.PUBLIC_URL}/static/font/`);
// Create an instance of the Document class
const doc = new wasmModule.Document();
// Specify the output file path
const outputFileName = 'HtmlStringToImage.png';
// Specify the HTML string
let HTML = "<html><head><title>HTML to Word Example</title><style>, body {font-family: 'Calibri';}, h1 {color: #FF5733; font-size: 24px; margin-bottom: 20px;}, p {color: #333333; font-size: 16px; margin-bottom: 10px;}";
HTML += "ul {list-style-type: disc; margin-left: 20px; margin-bottom: 15px;}, li {font-size: 14px; margin-bottom: 5px;}, table {border-collapse: collapse; width: 100%; margin-bottom: 20px;}";
HTML += "th, td {border: 1px solid #CCCCCC; padding: 8px; text-align: left;}, th {background-color: #F2F2F2; font-weight: bold;}, td {color: #0000FF;}</style></head>";
HTML += "<body><h1>This is a Heading</h1><p>This is a paragraph demonstrating the conversion of HTML to Word document.</p><p>Here's an example of an unordered list:</p><ul><li>Item 1</li><li>Item 2</li><li>Item 3</li></ul>";
HTML += "<p>Here's a table:</p><table><tr><th>Product</th><th>Quantity</th><th>Price</th></tr><tr><td>Jacket</td><td>30</td><td>$150</td></tr><tr><td>Sweater</td><td>25</td><td>$99</td></tr></table></body></html>";
// Add a section to the document
let section = doc.AddSection();
// Add a paragraph to the section
let paragraph = section.AddParagraph();
// Append the HTML string to the paragraph
paragraph.AppendHTML(HTML.toString('utf8', 0, HTML.length));
// Save the first page as an image stream
let image = doc.SaveImageToStreams({ pageIndex: 0, type: wasmModule.ImageType.Bitmap });
// Save the image stream as a PNG file
image.Save(outputFileName);
// Read the generated image from VFS
const modifiedFileArray = window.dotnetRuntime.Module.FS.readFile(outputFileName);
// Create a Blog object from the image file
const modifiedFile = new Blob([modifiedFileArray], { type: 'image/png' });
// Create a URL for the Blob
const url = URL.createObjectURL(modifiedFile);
// Create an anchor element to trigger the download
const a = document.createElement("a");
a.href = url;
a.download = outputFileName;
document.body.appendChild(a);
a.click();
document.body.removeChild(a);
URL.revokeObjectURL(url);
// Clean up resources
doc.Dispose();
}
};
return (
<div style={{ textAlign: 'center', height: '300px' }}>
<h1>Convert an HTML String to an Image Using JavaScript in React</h1>
<button onClick={HtmlStringToImage} disabled={!wasmModule}>
Convert
</button>
</div>
);
}
export default App;

Get a Free License
To fully experience the capabilities of Spire.Doc for JavaScript without any evaluation limitations, you can request a free 30-day trial license.
Extract Text from Word Documents with JavaScript in React
2025-01-16 00:53:41 Written by AdministratorThe seamless integration of document processing capabilities into web applications has become increasingly vital for enhancing user experience and streamlining workflows. For developers working within the React ecosystem, the ability to extract text from Word documents using JavaScript allows for the dynamic presentation of content, enabling users to easily import, edit, and interact with text data directly within a web interface. In this article, we will explore how to use Spire.Doc for JavaScript to extract text from Word documents in React applications.
- Extract All Text from a Word Document Using JavaScript
- Extract Text from Specific Sections or Paragraphs in a Word Document
- Extract Text from a Word Document Based on Paragraph Styles
Install Spire.Doc for JavaScript
To get started with extracting text from Word documents in a React application, you can either download Spire.Doc for JavaScript from our website or install it via npm with the following command:
npm i spire.office
The downloaded product package integrates Spire.Doc for JavaScript, Spire.XLS for JavaScript, Spire.PDF for JavaScript, and Spire.Presentation for JavaScript. To use the features of Spire.Doc for JavaScript, you need to copy the corresponding files (spire.doc.js, Spire.Doc.Wasm.zip, spire.common.js, Spire.Common.Wasm.zip, and the _framework folder) to the public folder of your project. To ensure proper text rendering, you can add relevant font files with a custom path. In the following example, the font is added to the path: public\static\font.
For more details, refer to the documentation: How to Integrate Spire.Doc for JavaScript in a React Project
Extract All Text from a Word Document Using JavaScript
To extract the complete text content from a Word document, Spire.Doc for JavaScript offers the Document.GetText() method. This method retrieves all the text in a document and returns it as a string, enabling efficient access to the content. The implementation steps are as follows:
- Load the spire.doc.js file to initialize the WebAssembly module.
- Load the Word file into the virtual file system using the window.spire.FetchFileToVFS method.
- Create a Document instance in the WebAssembly module using the new wasmModule.Document() method.
- Load the Word document into the Document instance with the Document.LoadFromFile() method.
- Retrieve the document's text as a string using the Document.GetText() method.
- Process the extracted text, such as downloading it as a text file or performing additional operations.
- JavaScript
import React, { useState, useEffect } from 'react';
function App() {
const [wasmModule, setWasmModule] = useState(null);
// Load Spire.Doc
useEffect(() => {
(async () => {
try {
const publicUrl = process.env.PUBLIC_URL || '';
const spireModule = await import(/* webpackIgnore: true */ `${publicUrl}/spire.doc.js`);
const rawModule = spireModule.default || spireModule;
window.wasmModule = typeof rawModule === 'function'
? await rawModule({ locateFile: p => p.endsWith('.wasm') ? `${publicUrl}/${p}` : p })
: rawModule;
setWasmModule(window.wasmModule);
} catch (error) {
console.error('Failed to load spire.doc.js WASM module:', error);
}
})();
}, []);
// Function to extract all text from a Word document
const ExtractAllTextFromWord = async () => {
const wasmModule = window.wasmModule.spiredoc;
if (wasmModule) {
// Load the font files into the virtual file system (VFS)
await window.spire.FetchFileToVFS('Arial.ttf', '/Library/Fonts/', `${process.env.PUBLIC_URL}/static/font/`);
// Specify the input file name and the output file name
const inputFileName = 'Sample.docx';
const outputFileName = 'ExtractWordText.txt';
// Fetch the input file and add it to the VFS
await window.spire.FetchFileToVFS(inputFileName, '', `${process.env.PUBLIC_URL}/static/data/`);
// Create an instance of the Document class
const doc = new wasmModule.Document();
// Load the Word document
doc.LoadFromFile({ fileName: inputFileName });
// Get all text from the document
const documentText = doc.GetText();
// Release resources
doc.Dispose();
// Generate a Blob from the extracted text and trigger a download
const blob = new Blob([documentText], { type: 'text/plain' });
const url = URL.createObjectURL(blob);
const a = document.createElement("a");
a.href = url;
a.download = outputFileName;
document.body.appendChild(a);
a.click();
document.body.removeChild(a);
URL.revokeObjectURL(url);
}
};
return (
<div style={{ textAlign: 'center', height: '300px' }}>
<h1>Extract All Text from Word Documents Using JavaScript in React</h1>
<button onClick={ExtractAllTextFromWord} disabled={!wasmModule}>
Convert and Download
</button>
</div>
);
}
export default App;

Extract Text from Specific Sections or Paragraphs in a Word Document
When only specific sections or paragraphs of a Word document are needed, Spire.Doc for JavaScript offers the Section.Paragraphs.get_Item(index).Text method to extract text from individual paragraphs. The following steps outline the process:
- Load the spire.doc.js file to initialize the WebAssembly module.
- Use the window.spire.FetchFileToVFS method to load the Word file into the virtual file system.
- Create a Document instance using the new wasmModule.Document() method.
- Load the Word document into the Document instance with the Document.LoadFromFile() method.
- Access a specific section using the Document.Sections.get_Item() method.
- Extract text from a specific paragraph with the Section.Paragraphs.get_Item().Text property.
- To retrieve all text within a section, iterate through the section's paragraphs and concatenate their text into a single string.
- Process the extracted text, such as saving it to a file or performing further analysis.
- JavaScript
import React, { useState, useEffect } from 'react';
function App() {
const [wasmModule, setWasmModule] = useState(null);
// Load Spire.Doc
useEffect(() => {
(async () => {
try {
const publicUrl = process.env.PUBLIC_URL || '';
const spireModule = await import(/* webpackIgnore: true */ `${publicUrl}/spire.doc.js`);
const rawModule = spireModule.default || spireModule;
window.wasmModule = typeof rawModule === 'function'
? await rawModule({ locateFile: p => p.endsWith('.wasm') ? `${publicUrl}/${p}` : p })
: rawModule;
setWasmModule(window.wasmModule);
} catch (error) {
console.error('Failed to load spire.doc.js WASM module:', error);
}
})();
}, []);
// Function to extract text from a specific part of a Word document
const ExtractTextFromWordPart = async () => {
const wasmModule = window.wasmModule.spiredoc;
if (wasmModule) {
// Load the font files into the virtual file system (VFS)
await window.spire.FetchFileToVFS('Arial.ttf', '/Library/Fonts/', `${process.env.PUBLIC_URL}/static/font/`);
// Specify the input file name and the output file name
const inputFileName = 'Sample.docx';
const outputFileName = 'ExtractWordText.txt';
// Fetch the input file and add it to the VFS
await window.spire.FetchFileToVFS(inputFileName, '', `${process.env.PUBLIC_URL}/static/data/`);
// Create an instance of the Document class
const doc = new wasmModule.Document();
// Load the Word document
doc.LoadFromFile({ fileName: inputFileName });
// Get a specific section from the document
const section = doc.Sections.get_Item(1);
// Get the text of a specific paragraph in the section
//const paragraphText = section.Paragraphs.get_Item(1).Text;
// Extract all text from the section
let sectionText = "";
for (let i = 0; i < section.Paragraphs.Count; i++) {
// Extract the text from the paragraphs
const text = section.Paragraphs.get_Item(i).Text;
sectionText += text + "\n";
}
// Release resources
doc.Dispose();
// Generate a Blob from the extracted text and trigger a download
const blob = new Blob([sectionText], { type: 'text/plain' });
const url = URL.createObjectURL(blob);
const a = document.createElement("a");
a.href = url;
a.download = outputFileName;
document.body.appendChild(a);
a.click();
document.body.removeChild(a);
URL.revokeObjectURL(url);
}
};
return (
<div style={{ textAlign: 'center', height: '300px' }}>
<h1>Extract Text from a Specific Part of a Word Document Using JavaScript in React</h1>
<button onClick={ExtractTextFromWordPart} disabled={!wasmModule}>
Convert and Download
</button>
</div>
);
}
export default App;

Extract Text from a Word Document Based on Paragraph Styles
When extracting text formatted with specific paragraph styles, the Paragraph.StyleName property can be utilized to identify and filter paragraphs by their styles. This approach is beneficial for structured documents with distinct headings or other styled elements. The implementation process is as follows:
- Load the spire.doc.js file to initialize the WebAssembly module.
- Load the Word file into the virtual file system using the window.spire.FetchFileToVFS() method.
- Create a Document instance in the WebAssembly module with the new wasmModule.Document() method.
- Load the Word document into the Document instance using the Document.LoadFromFile() method.
- Define the target style name or retrieve one from the document.
- Iterate through the document's sections and their paragraphs:
- Use the Paragraph.StyleName property to identify each paragraph's style.
- Compare the paragraph's style name with the target style. If they match, retrieve the paragraph's text using the Paragraph.Text property.
- Process the retrieved text, such as saving it to a file or using it for further operations.
- JavaScript
import React, { useState, useEffect } from 'react';
function App() {
const [wasmModule, setWasmModule] = useState(null);
// Load Spire.Doc
useEffect(() => {
(async () => {
try {
const publicUrl = process.env.PUBLIC_URL || '';
const spireModule = await import(/* webpackIgnore: true */ `${publicUrl}/spire.doc.js`);
const rawModule = spireModule.default || spireModule;
window.wasmModule = typeof rawModule === 'function'
? await rawModule({ locateFile: p => p.endsWith('.wasm') ? `${publicUrl}/${p}` : p })
: rawModule;
setWasmModule(window.wasmModule);
} catch (error) {
console.error('Failed to load spire.doc.js WASM module:', error);
}
})();
}, []);
// Function to extract text from a Word document based on paragraph styles
const ExtractTextByParagraphStyle = async () => {
const wasmModule = window.wasmModule.spiredoc;
if (wasmModule) {
// Load the font files into the virtual file system (VFS)
await window.spire.FetchFileToVFS('Arial.ttf', '/Library/Fonts/', `${process.env.PUBLIC_URL}/static/font/`);
// Specify the input file name and the output file name
const inputFileName = 'Sample.docx';
const outputFileName = 'ExtractWordText.txt';
// Fetch the input file and add it to the VFS
await window.spire.FetchFileToVFS(inputFileName, '', `${process.env.PUBLIC_URL}/static/data/`);
// Create an instance of the Document class
const doc = new wasmModule.Document();
// Load the Word document
doc.LoadFromFile({ fileName: inputFileName });
// Define the style name or get the style name of the target paragraph style
const styleName = 'Heading2';
// const styleName = doc.Sections.get_Item(2).Paragraphs.get_Item(2).StyleName;
// Array to store extracted text
let paragraphStyleText = [];
// Iterate through the sections in the document
for (let sectionIndex = 0; sectionIndex < doc.Sections.Count; sectionIndex++) {
// Get the current section
const section = doc.Sections.get_Item(sectionIndex);
// Iterate through the paragraphs in the section
for (let paragraphIndex = 0; paragraphIndex < section.Paragraphs.Count; paragraphIndex++) {
// Get the current paragraph
const paragraph = section.Paragraphs.get_Item(paragraphIndex);
// Get the style name of the paragraph
const paraStyleName = paragraph.StyleName;
// Check if the style name matches the target style
if (paraStyleName === styleName) {
// Extract the text from the paragraph
const paragraphText = paragraph.Text;
console.log(paragraphText);
// Append the extracted text to the array
paragraphStyleText.push(paragraphText);
}
}
}
// Release resources
doc.Dispose();
// Generate a Blob from the extracted text and trigger a download
const text = paragraphStyleText.join('\n');
const blob = new Blob([text], { type: 'text/plain' });
const url = URL.createObjectURL(blob);
const a = document.createElement("a");
a.href = url;
a.download = outputFileName;
document.body.appendChild(a);
a.click();
document.body.removeChild(a);
URL.revokeObjectURL(url);
}
};
return (
<div style={{ textAlign: 'center', height: '300px' }}>
<h1>Extract Text from Word Documents by Paragraph Style Using JavaScript in React</h1>
<button onClick={ExtractTextByParagraphStyle} disabled={!wasmModule}>
Convert and Download
</button>
</div>
);
}
export default App;

Get a Free License
To fully experience the capabilities of Spire.Doc for JavaScript without any evaluation limitations, you can request a free 30-day trial license.
Apply Fonts in a Word Document with JavaScript in React
2025-01-15 00:59:57 Written by AdministratorApplying fonts in a Word document significantly enhances its visual appeal and readability. The choice of font can influence how the content is perceived, allowing you to convey tone and mood effectively. By selecting appropriate fonts, you can emphasize key points, guide the reader's attention, and create a cohesive and polished presentation.
In this article, you will learn how to apply fonts in a Word document in React using Spire.Doc for JavaScript.
- Apply a Font Style to a Paragraph in Word
- Apply Multiple Font Styles to a Paragraph in Word
- Apply a Private Font in a Word Document
Install Spire.Doc for JavaScript
To get started with applying fonts in Word in a React application, you can either download Spire.Doc for JavaScript from our website or install it via npm with the following command:
npm i spire.office
The downloaded product package integrates Spire.Doc for JavaScript, Spire.XLS for JavaScript, Spire.PDF for JavaScript, and Spire.Presentation for JavaScript. To use the features of Spire.Doc for JavaScript, you need to copy the corresponding files (spire.doc.js, Spire.Doc.Wasm.zip, spire.common.js, Spire.Common.Wasm.zip, and the _framework folder) to the public folder of your project. To ensure proper text rendering, you can add relevant font files with a custom path. In the following example, the font is added to the path: public\static\font.
For more details, refer to the documentation: How to Integrate Spire.Doc for JavaScript in a React Project
Apply a Font Style to a Paragraph in Word
Applying a font style to a paragraph in Microsoft Word is a fundamental skill that enhances the readability and overall appearance of your document.
Spire.Doc for JavaScript provides the ParagraphStyle class, enabling developers to define multiple text attributes, including font name, size, style, and color, all within a single object. After the style object is created, you can easily format a paragraph by using the Paragraph.ApplyStyle() method.
The following are the steps to apply a font style to a paragraph with JavaScript in React:
- Create a Document object using the new wasmModule.Document() method.
- Load the Word file using the Document.LoadFromFile() method.
- Add a paragraph to the document using the Document.LastSection.AddParagraph() method.
- Create a ParagraphStyle object, specifying the font name, font size, font style, and text color.
- Add the style to the document using the Document.Styles.Add() method.
- Apply the style to the paragraph using the Paragraph.ApplyStyle() method.
- Save the document to a different Word file.
- JavaScript
import React, { useState, useEffect } from 'react';
function App() {
const [wasmModule, setWasmModule] = useState(null);
// Load Spire.Doc
useEffect(() => {
(async () => {
try {
const publicUrl = process.env.PUBLIC_URL || '';
const spireModule = await import(/* webpackIgnore: true */ `${publicUrl}/spire.doc.js`);
const rawModule = spireModule.default || spireModule;
window.wasmModule = typeof rawModule === 'function'
? await rawModule({ locateFile: p => p.endsWith('.wasm') ? `${publicUrl}/${p}` : p })
: rawModule;
setWasmModule(window.wasmModule);
} catch (error) {
console.error('Failed to load spire.doc.js WASM module:', error);
}
})();
}, []);
// Function to set font
const SetFont = async () => {
const wasmModule = window.wasmModule.spiredoc;
if (wasmModule) {
// Load the font files into the virtual file system (VFS)
await window.spire.FetchFileToVFS('times.ttf', '/Library/Fonts/', `${process.env.PUBLIC_URL}/static/font/`);
await window.spire.FetchFileToVFS('timesbd.ttf', '/Library/Fonts/', `${process.env.PUBLIC_URL}/static/font/`);
await window.spire.FetchFileToVFS('timesbi.ttf', '/Library/Fonts/', `${process.env.PUBLIC_URL}/static/font/`);
await window.spire.FetchFileToVFS('timesi.ttf', '/Library/Fonts/', `${process.env.PUBLIC_URL}/static/font/`);
// Specify the input file name and the output file name
const inputFileName = 'input.docx';
const outputFileName = 'output.docx';
// Fetch the input file and add it to the VFS
await window.spire.FetchFileToVFS(inputFileName, '', `${process.env.PUBLIC_URL}/static/data/`);
// Create an instance of the Document class
const doc = new wasmModule.Document();
// Load the Word file
doc.LoadFromFile(inputFileName);
// Add a section
let section = doc.LastSection;
// Add a paragraph
let paragraph = section.AddParagraph();
// Append text to the paragraph
paragraph.AppendText('JavaScript is essential for modern web development, offering a rich ecosystem and ' +
'a wide range of applications. Its ability to create responsive, interactive experiences ' +
'makes it a favored choice among developers.');
// Create a paragraph style,specifying font name, font size, and text color
let paragraphStyle = new wasmModule.ParagraphStyle(doc);
paragraphStyle.Name = 'newStyle';
paragraphStyle.CharacterFormat.FontName = 'Times New Roman'
paragraphStyle.CharacterFormat.FontSize = 13;
paragraphStyle.CharacterFormat.TextColor = wasmModule.Color.get_Blue();
// Add the style to the document
doc.Styles.Add(paragraphStyle);
// Apply the style to the paragraph
paragraph.ApplyStyle(paragraphStyle.Name);
// Save the document to the specified path
doc.SaveToFile({ fileName: outputFileName, fileFormat: wasmModule.FileFormat.Docx2013 });
// Read the generated Word file
const modifiedFileArray = window.dotnetRuntime.Module.FS.readFile(outputFileName);
// Create a Blob object from the Word file
const modifiedFile = new Blob([modifiedFileArray], { type: 'application/vnd.openxmlformats-officedocument.wordprocessingml.document' });
// Create a URL for the Blob
const url = URL.createObjectURL(modifiedFile);
// Create an anchor element to trigger the download
const a = document.createElement('a');
a.href = url;
a.download = outputFileName;
document.body.appendChild(a);
a.click();
document.body.removeChild(a);
URL.revokeObjectURL(url);
// Clean up resources
doc.Dispose();
}
};
return (
<div style={{ textAlign: 'center', height: '300px' }}>
<h1>Apply Fonts in a Word Document in React</h1>
<button onClick={SetFont} disabled={!wasmModule}>
Apply
</button>
</div>
);
}
export default App;
Run the code to launch the React app at localhost:3000. Click "Apply", and a "Save As" window will appear, prompting you to save the output file in your chosen folder.

Below is a screenshot of the generated Word document:

Apply Multiple Font Styles to a Paragraph in Word
Applying multiple font styles to different parts of a paragraph allows you to highlight key points or sections, making your content more engaging for readers.
The Paragraph.AppendText() method returns a TextRange object, which offers simple APIs for formatting text within that range. When you call AppendText() multiple times, the paragraph's text is divided into distinct text ranges, allowing for individual styling with different fonts.
The following are the steps to apply multiple font styles to a paragraph using JavaScript in React:
- Load the font files you plan to use and the input Word file into the virtual file system (VFS).
- Create a Document object using the new wasmModule.Document() method.
- Load the Word file using the Document.LoadFromFile() method.
- Add a paragraph to the document using the Document.LastSection.AddParagraph() method.
- Append text to the paragraph using the Paragraph.AppendText() method, which returns a TextRange object.
- Append more text that needs to be styled differently to the paragraph and return different TextRange objects.
- Create a ParagraphStyle object with the basic font information and apply it to the paragraph.
- Change the font name, style, size and text color of the specified text range using the properties under the specific TextRange object.
- Save the document to a different Word file.
- JavaScript
import React, { useState, useEffect } from 'react';
function App() {
const [wasmModule, setWasmModule] = useState(null);
// Load Spire.Doc
useEffect(() => {
(async () => {
try {
const publicUrl = process.env.PUBLIC_URL || '';
const spireModule = await import(/* webpackIgnore: true */ `${publicUrl}/spire.doc.js`);
const rawModule = spireModule.default || spireModule;
window.wasmModule = typeof rawModule === 'function'
? await rawModule({ locateFile: p => p.endsWith('.wasm') ? `${publicUrl}/${p}` : p })
: rawModule;
setWasmModule(window.wasmModule);
} catch (error) {
console.error('Failed to load spire.doc.js WASM module:', error);
}
})();
}, []);
// Function to set font
const SetFont = async () => {
const wasmModule = window.wasmModule.spiredoc;
if (wasmModule) {
// Load the font files into the virtual file system (VFS)
await window.spire.FetchFileToVFS('times.ttf', '/Library/Fonts/', `${process.env.PUBLIC_URL}/static/font/`);
await window.spire.FetchFileToVFS('timesbd.ttf', '/Library/Fonts/', `${process.env.PUBLIC_URL}/static/font/`);
await window.spire.FetchFileToVFS('timesbi.ttf', '/Library/Fonts/', `${process.env.PUBLIC_URL}/static/font/`);
await window.spire.FetchFileToVFS('timesi.ttf', '/Library/Fonts/', `${process.env.PUBLIC_URL}/static/font/`);
// Specify the input file name and the output file name
const inputFileName = 'input.docx';
const outputFileName = 'output.docx';
// Fetch the input file and add it to the VFS
await window.spire.FetchFileToVFS(inputFileName, '', `${process.env.PUBLIC_URL}/static/data/`);
// Create an instance of the Document class
const doc = new wasmModule.Document();
// Load the Word file
doc.LoadFromFile(inputFileName);
// Add a section
let section = doc.LastSection;
// Add a paragraph
let paragraph = section.AddParagraph();
// Append text to the paragraph
let range_one = paragraph.AppendText('JavaScript is essential for ');
let range_two = paragraph.AppendText('modern web development');
let range_three = paragraph.AppendText(', offering a rich ecosystem and a wide range of applications. Its ability to create ');
let range_four = paragraph.AppendText('responsive, interactive experiences')
let range_five = paragraph.AppendText(' makes it a favored choice among developers.')
// Create a paragraph style
let paragraphStyle = new wasmModule.ParagraphStyle(doc);
paragraphStyle.Name = 'newStyle';
paragraphStyle.CharacterFormat.FontName = 'Times New Roman'
paragraphStyle.CharacterFormat.FontSize = 13;
paragraphStyle.CharacterFormat.TextColor = wasmModule.Color.get_Black();
// Add the style to the document
doc.Styles.Add(paragraphStyle);
// Apply the style to the paragraph
paragraph.ApplyStyle(paragraphStyle.Name);
// Change the font style of the second text range
range_two.CharacterFormat.TextColor = wasmModule.Color.get_Blue();
range_two.CharacterFormat.Bold = true;
range_two.CharacterFormat.UnderlineStyle = wasmModule.UnderlineStyle.Single;
// Change the font style of the fourth text range
range_four.CharacterFormat.TextColor = wasmModule.Color.get_Blue();
range_four.CharacterFormat.Italic = true;
// Save the document to the specified path
doc.SaveToFile({ fileName: outputFileName, fileFormat: wasmModule.FileFormat.Docx2013 });
// Read the generated Word file
const modifiedFileArray = window.dotnetRuntime.Module.FS.readFile(outputFileName);
// Create a Blob object from the Word file
const modifiedFile = new Blob([modifiedFileArray], { type: 'application/vnd.openxmlformats-officedocument.wordprocessingml.document' });
// Create a URL for the Blob
const url = URL.createObjectURL(modifiedFile);
// Create an anchor element to trigger the download
const a = document.createElement('a');
a.href = url;
a.download = outputFileName;
document.body.appendChild(a);
a.click();
document.body.removeChild(a);
URL.revokeObjectURL(url);
// Clean up resources
doc.Dispose();
}
};
return (
<div style={{ textAlign: 'center', height: '300px' }}>
<h1>Set Fonts in a Word Document in React</h1>
<button onClick={SetFont} disabled={!wasmModule}>
Apply Multiple Fonts
</button>
</div>
);
}
export default App;

Apply a Private Font in a Word Document
Using a private font in a Word document can give your project a unique flair and reflect your personal or brand identity.
To apply a private font, use the TextRange.CharacterFormat.FontName property. To maintain a uniform look on various devices, it's advisable to embed the font within the document. You can do this by first loading the font file into the virtual file system using window.spire.FetchFileToVFS.
Then, employ the Document.AddPrivateFont() method to include the font in the document. Additionally, activate font embedding by setting Document.EmbedFontsInFile to true, which ensures the private font is retained in the final document.
The following are the steps to apply a private font in Word using JavaScript:
- Load the font files you plan to use and the input Word file into the virtual file system (VFS).
- Create a Document object using the new wasmModule.Document() method.
- Load the Word file using the Document.LoadFromFile() method.
- Add a paragraph to the document using the Document.LastSection.AddParagraph() method.
- Append text to the paragraph using the Paragraph.AppendText() method, which returns a TextRange object.
- Apply the font to the paragraph using the TextRange.CharacterFormat.FontName property.
- Add the font to document using the Document.AddPrivateFont() method.
- Embed the font in the document by setting Document.EmbedFontsInFile to true.
- Save the document to a different Word file.
- JavaScript
import React, { useState, useEffect } from 'react';
function App() {
const [wasmModule, setWasmModule] = useState(null);
// Load Spire.Doc
useEffect(() => {
(async () => {
try {
const publicUrl = process.env.PUBLIC_URL || '';
const spireModule = await import(/* webpackIgnore: true */ `${publicUrl}/spire.doc.js`);
const rawModule = spireModule.default || spireModule;
window.wasmModule = typeof rawModule === 'function'
? await rawModule({ locateFile: p => p.endsWith('.wasm') ? `${publicUrl}/${p}` : p })
: rawModule;
setWasmModule(window.wasmModule);
} catch (error) {
console.error('Failed to load spire.doc.js WASM module:', error);
}
})();
}, []);
// Function to set font
const SetFont = async () => {
const wasmModule = window.wasmModule.spiredoc;
if (wasmModule) {
// Load the font files into the virtual file system (VFS)
await window.spire.FetchFileToVFS('FreebrushScriptPLng.ttf', '/Library/Fonts/', `${process.env.PUBLIC_URL}/static/font/`);
// Specify the input file name and the output file name
const inputFileName = 'input.docx';
const outputFileName = 'output.docx';
// Fetch the input file and add it to the VFS
await window.spire.FetchFileToVFS(inputFileName, '', `${process.env.PUBLIC_URL}/static/data/`);
// Create an instance of the Document class
const doc = new wasmModule.Document();
// Load the Word file
doc.LoadFromFile(inputFileName);
// Add a section
let section = doc.LastSection;
// Add a paragraph
let paragraph = section.AddParagraph();
// Append text to the paragraph
let textRange = paragraph.AppendText('JavaScript is essential for modern web development, offering a rich ecosystem and '+
'a wide range of applications. Its ability to create responsive, interactive experiences '+
'makes it a favored choice among developers.');
// Apply the private font to the text range
textRange.CharacterFormat.FontName = 'Freebrush Script'
textRange.CharacterFormat.FontSize = 13;
textRange.CharacterFormat.TextColor = wasmModule.Color.get_Blue();
// Embed the private font in the document
doc.AddPrivateFont(new wasmModule.PrivateFontPath("Freebrush Script", "FreebrushScriptPLng.ttf"))
// Allow embedding font in document
doc.EmbedFontsInFile = true;
// Save the document to the specified path
doc.SaveToFile({fileName: outputFileName, fileFormat: wasmModule.FileFormat.Docx2013});
// Read the generated Word file
const modifiedFileArray =window.dotnetRuntime.Module.FS.readFile(outputFileName);
// Create a Blob object from the Word file
const modifiedFile = new Blob([modifiedFileArray], { type: 'application/vnd.openxmlformats-officedocument.wordprocessingml.document' });
// Create a URL for the Blob
const url = URL.createObjectURL(modifiedFile);
// Create an anchor element to trigger the download
const a = document.createElement('a');
a.href = url;
a.download = outputFileName;
document.body.appendChild(a);
a.click();
document.body.removeChild(a);
URL.revokeObjectURL(url);
// Clean up resources
doc.Dispose();
}
};
return (
<div style={{ textAlign: 'center', height: '300px' }}>
<h1>Apply Fonts in a Word Document in React</h1>
<button onClick={SetFont} disabled={!wasmModule}>
Apply
</button>
</div>
);
}
export default App;

Get a Free License
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