通过C++的JavaScript将PdfSaveOptions和ImageOrPrintOptions的DefaultFont属性设置为优先
可能的使用场景
在设置 PdfSaveOptions 和 ImageOrPrintOptions 的 DefaultFont 属性时，您可能希望保存为 PDF 或图像时将该 DefaultFont 设置为工作簿中所有没有安装的字体的文本。
通常，在保存为PDF或图片时，C++的Aspose.Cells for JavaScript会首先尝试设置工作簿的默认字体（即Workbook.DefaultStyle.Font）。如果工作簿的默认字体仍不能正确显示/渲染文本，Aspose.Cells将尝试使用PdfSaveOptions/ImageOrPrintOptions中DefaultFont属性指定的字体进行渲染。
为了符合您的期望，我们在 PdfSaveOptions/ImageOrPrintOptions 中提供了一个名为"CheckWorkbookDefaultFont“的布尔属性。您可以将其设置为 false 以禁用尝试工作簿的默认字体，或者让 PdfSaveOptions/ImageOrPrintOptions 中的 DefaultFont 设置具有优先级。
设置PdfSaveOptions/ImageOrPrintOptions的DefaultFont属性
以下示例代码打开一个Excel文件。第一个工作表的A1单元格内设置了一段文本“Christmas Time Font text”。字体名为“Christmas Time Personal Use”，该字体未安装在机器上。我们将PdfSaveOptions/ImageOrPrintOptions的DefaultFont属性设置为“Times New Roman”。同时将布尔属性CheckWorkbookDefaultFont设置为“false”，确保A1单元格的文本使用“Times New Roman”字体渲染，而不是使用默认字体（此处为“Calibri”）。该代码将第一个工作表渲染为PNG和TIFF图像格式，最后输出为PDF文件。
这是示例代码中使用的模板文件的屏幕截图。
设置ImageOrPrintOptions.defaultFont属性为“Times New Roman”后生成的PNG图像示意。
设置ImageOrPrintOptions.defaultFont属性为“Times New Roman”后，输出的TIF图像。
在设置 PdfSaveOptions.defaultFont 属性为 “Times New Roman” 后，查看输出 PDF 文件。
示例代码
<!DOCTYPE html>
<html>
<head>
<title>Aspose.Cells Example</title>
</head>
<body>
<h1>Set Default Font for Export (PNG, TIFF, PDF)</h1>
<input type="file" id="fileInput" accept=".xls,.xlsx,.csv" />
<button id="runExample">Run Example</button>
<div>
<a id="downloadPng" style="display: none;">Download PNG</a><br/>
<a id="downloadTiff" style="display: none;">Download TIFF</a><br/>
<a id="downloadPdf" style="display: none;">Download PDF</a>
</div>
<div id="result"></div>
</body>
<script src="aspose.cells.js.min.js"></script>
<script type="text/javascript">
const { Workbook, SaveFormat, ImageOrPrintOptions, ImageType, SheetRender, WorkbookRender, PdfSaveOptions } = AsposeCells;
const readyPromise = AsposeCells.onReady({
license: "/lic/aspose.cells.enc",
fontPath: "/fonts/",
fontList: [
"arial.ttf",
"NotoSansSC-Regular.ttf"
]
}).then(() => {
console.log("Aspose.Cells initialized");
});
document.getElementById('runExample').addEventListener('click', async () => {
const resultEl = document.getElementById('result');
const fileInput = document.getElementById('fileInput');
if (!fileInput.files.length) {
resultEl.innerHTML = '<p style="color: red;">Please select an Excel file.</p>';
return;
}
await readyPromise;
const file = fileInput.files[0];
const arrayBuffer = await file.arrayBuffer();
const workbook = new Workbook(new Uint8Array(arrayBuffer));
// Rendering to PNG while setting checkWorkbookDefaultFont = false and defaultFont to Times New Roman
const imgOpt = new ImageOrPrintOptions();
imgOpt.imageType = ImageType.Png;
imgOpt.checkWorkbookDefaultFont = false;
imgOpt.defaultFont = "Times New Roman";
const sr = new SheetRender(workbook.worksheets.get(0), imgOpt);
const pngData = sr.toImage(0);
const pngBlob = new Blob([pngData], { type: 'image/png' });
const downloadPng = document.getElementById('downloadPng');
downloadPng.href = URL.createObjectURL(pngBlob);
downloadPng.download = 'out1_imagePNG.png';
downloadPng.style.display = 'inline-block';
downloadPng.textContent = 'Download PNG';
// Rendering to TIFF while setting checkWorkbookDefaultFont = false and defaultFont to Times New Roman
imgOpt.imageType = ImageType.Tiff;
const wr = new WorkbookRender(workbook, imgOpt);
const tiffData = wr.toImage();
const tiffBlob = new Blob([tiffData], { type: 'image/tiff' });
const downloadTiff = document.getElementById('downloadTiff');
downloadTiff.href = URL.createObjectURL(tiffBlob);
downloadTiff.download = 'out1_imageTIFF.tiff';
downloadTiff.style.display = 'inline-block';
downloadTiff.textContent = 'Download TIFF';
// Rendering to PDF while setting the default font and checkWorkbookDefaultFont
const saveOptions = new PdfSaveOptions();
saveOptions.defaultFont = "Times New Roman";
saveOptions.checkWorkbookDefaultFont = false;
const pdfData = workbook.save(SaveFormat.Pdf, saveOptions);
const pdfBlob = new Blob([pdfData], { type: 'application/pdf' });
const downloadPdf = document.getElementById('downloadPdf');
downloadPdf.href = URL.createObjectURL(pdfBlob);
downloadPdf.download = 'out1_pdf.pdf';
downloadPdf.style.display = 'inline-block';
downloadPdf.textContent = 'Download PDF';
resultEl.innerHTML = '<p style="color: green;">Export completed. Click the links above to download the generated files.</p>';
});
</script>
</html>