在用C++通过JavaScript加载工作簿或工作表时筛选对象
Contents
[
Hide
]
可能的使用场景
请在使用LoadOptions.loadFilter属性筛选工作簿数据时使用。但如果你想筛选单个工作表中的数据，你需要重写LoadFilter.startSheet(Worksheet)方法。在创建或使用LoadFilter时，提供适当的LoadDataFilterOptions枚举值。
LoadDataFilterOptions枚举具有以下可能值。
- 所有
- 文档设置
- 单元格空白
- 单元格布尔
- 单元格数据
- 单元格错误
- 单元格数值
- 单元格字符串
- 单元格值
- Chart
- 条件格式
- 数据验证
- 定义名称
- 文档属性
- 公式
- 超链接
- 合并区域
- 数据透视表
- 设置
- 形状
- 表单数据
- 表格设置
- 结构
- 样式
- 表
- VBA
- Xml映射
加载工作簿时过滤对象
以下示例代码说明了如何从工作簿中筛选图表。请查看此代码中使用的示例excel文件和由此生成的输出PDF。从输出PDF中可以看出，所有图表都已从工作簿中筛选出。
<!DOCTYPE html>
<html>
<head>
<title>Aspose.Cells Example</title>
</head>
<body>
<h1>Filter Charts and Save to PDF Example</h1>
<input type="file" id="fileInput" accept=".xls,.xlsx,.csv" />
<button id="runExample">Run Example</button>
<a id="downloadLink" style="display: none;">Download Result</a>
<div id="result"></div>
</body>
<script src="aspose.cells.js.min.js"></script>
<script type="text/javascript">
const { Workbook, SaveFormat, LoadOptions, LoadFilter, LoadDataFilterOptions, PdfSaveOptions } = AsposeCells;
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 fileInput = document.getElementById('fileInput');
const resultDiv = document.getElementById('result');
const downloadLink = document.getElementById('downloadLink');
if (!fileInput.files.length) {
resultDiv.innerHTML = '<p style="color: red;">Please select an Excel file.</p>';
return;
}
const file = fileInput.files[0];
const arrayBuffer = await file.arrayBuffer();
// Create load options and filter out charts
const lOptions = new LoadOptions();
lOptions.loadFilter = new LoadFilter(LoadDataFilterOptions.All & ~LoadDataFilterOptions.Chart);
// Load the workbook with the above filter
const workbook = new Workbook(new Uint8Array(arrayBuffer), lOptions);
// Create PDF save options and set one page per sheet
const pOptions = new PdfSaveOptions();
pOptions.onePagePerSheet = true;
// Save the workbook in PDF format
const outputData = workbook.save(SaveFormat.Pdf, pOptions);
const blob = new Blob([outputData], { type: 'application/pdf' });
downloadLink.href = URL.createObjectURL(blob);
downloadLink.download = 'sampleFilterCharts.pdf';
downloadLink.style.display = 'block';
downloadLink.textContent = 'Download PDF File';
resultDiv.innerHTML = '<p style="color: green;">Workbook saved to PDF (charts filtered out). Click the download link to get the PDF.</p>';
});
</script>
</html>
加载工作表时过滤对象
以下示例代码加载了源excel文件，并使用自定义过滤器从其工作表中筛选以下数据。
- 它会从名为NoCharts的工作表中筛选图表。
- 它会从名为NoShapes的工作表中筛选形状。
- 它会从名为NoConditionalFormatting的工作表中筛选条件格式。
一旦使用自定义过滤器加载了源excel文件，它会逐个工作表地获取所有工作表的图像。以下是用于参考的输出图像。可以看出，第一张图像没有图表，第二张图像没有形状，第三张图像没有条件格式。
<!DOCTYPE html>
<html>
<head>
<title>Custom Load Filter Example</title>
</head>
<body>
<h1>Custom Load Filter Example</h1>
<input type="file" id="fileInput" accept=".xls,.xlsx,.csv" />
<button id="runExample">Run Example</button>
<a id="downloadLink" style="display: none;">Download Result</a>
<div id="result"></div>
</body>
<script src="aspose.cells.js.min.js"></script>
<script type="text/javascript">
const { Workbook, SaveFormat, Utils } = AsposeCells;
AsposeCells.onReady({
license: "/lic/aspose.cells.enc",
fontPath: "/fonts/",
fontList: [
"arial.ttf",
"NotoSansSC-Regular.ttf"
]
}).then(() => {
console.log("Aspose.Cells initialized");
});
// Converted CustomLoadFilter class
class CustomLoadFilter extends AsposeCells.LoadFilter {
startSheet(sheet) {
if (sheet.name === "NoCharts") {
// Load everything and filter charts
this.loadDataFilterOptions = AsposeCells.LoadDataFilterOptions.All & ~AsposeCells.LoadDataFilterOptions.Chart;
}
if (sheet.name === "NoShapes") {
// Load everything and filter shapes
this.loadDataFilterOptions = AsposeCells.LoadDataFilterOptions.All & ~AsposeCells.LoadDataFilterOptions.Drawing;
}
if (sheet.name === "NoConditionalFormatting") {
// Load everything and filter conditional formatting
this.loadDataFilterOptions = AsposeCells.LoadDataFilterOptions.All & ~AsposeCells.LoadDataFilterOptions.ConditionalFormatting;
}
}
}
document.getElementById('runExample').addEventListener('click', async () => {
const fileInput = document.getElementById('fileInput');
if (!fileInput.files.length) {
document.getElementById('result').innerHTML = '<p style="color: red;">Please select an Excel file.</p>';
return;
}
const file = fileInput.files[0];
const arrayBuffer = await file.arrayBuffer();
// Instantiating a Workbook object using the uploaded file
const workbook = new Workbook(new Uint8Array(arrayBuffer));
// Instantiate and (optionally) attach the custom load filter
const customFilter = new CustomLoadFilter();
// If the environment supports assigning a load filter to workbook, set it as a property
workbook.loadFilter = customFilter;
// Inform user that the filter class was created and assigned
document.getElementById('result').innerHTML = '<p style="color: green;">CustomLoadFilter created and assigned to workbook. You can download the (possibly unchanged) workbook below.</p>';
// Save the workbook back to a downloadable file
const outputData = workbook.save(SaveFormat.Xlsx);
const blob = new Blob([outputData]);
const downloadLink = document.getElementById('downloadLink');
downloadLink.href = URL.createObjectURL(blob);
downloadLink.download = 'output.xlsx';
downloadLink.style.display = 'block';
downloadLink.textContent = 'Download Excel File';
});
</script>
</html>
这是如何根据工作表名称使用CustomLoadFilter类。
<!DOCTYPE html>
<html>
<head>
<title>Aspose.Cells Example</title>
<meta charset="utf-8" />
<style>
body { font-family: Arial, sans-serif; margin: 20px; }
#downloadList a { display: block; margin: 6px 0; }
#result p { margin: 8px 0; }
</style>
</head>
<body>
<h1>Render Worksheets to PNG with Custom Load Filter</h1>
<input type="file" id="fileInput" accept=".xls,.xlsx,.csv" />
<button id="runExample">Run Example</button>
<div id="result"></div>
<div id="downloadList"></div>
</body>
<script src="aspose.cells.js.min.js"></script>
<script type="text/javascript">
const { Workbook, LoadOptions, ImageOrPrintOptions, SheetRender, ImageType } = AsposeCells;
AsposeCells.onReady({
license: "/lic/aspose.cells.enc",
fontPath: "/fonts/",
fontList: [
"arial.ttf",
"NotoSansSC-Regular.ttf"
]
}).then(() => {
console.log("Aspose.Cells initialized");
});
// Define CustomLoadFilter class (placeholder - adapt as needed)
// The original JavaScript code referenced a CustomLoadFilter implementation.
// This minimal implementation can be replaced with actual filtering logic.
class CustomLoadFilter {
constructor() {
}
// If the AsposeCells runtime expects specific methods on the filter,
// implement them here. This is a generic placeholder.
}
document.getElementById('runExample').addEventListener('click', async () => {
const resultDiv = document.getElementById('result');
const downloadList = document.getElementById('downloadList');
downloadList.innerHTML = '';
resultDiv.innerHTML = '';
const fileInput = document.getElementById('fileInput');
if (!fileInput.files.length) {
resultDiv.innerHTML = '<p style="color: red;">Please select an Excel file.</p>';
return;
}
const file = fileInput.files[0];
const arrayBuffer = await file.arrayBuffer();
// Prepare load options and assign custom load filter
const loadOpts = new LoadOptions();
loadOpts.loadFilter = new CustomLoadFilter();
// Instantiate workbook from uploaded file with load options
const workbook = new Workbook(new Uint8Array(arrayBuffer), loadOpts);
// Iterate through worksheets and render each to PNG
const sheetCount = workbook.worksheets.count;
for (let i = 0; i < sheetCount; i++) {
const worksheet = workbook.worksheets.get(i);
// Create image options
const imageOpts = new ImageOrPrintOptions();
imageOpts.onePagePerSheet = true;
imageOpts.imageType = ImageType.Png;
// Render worksheet to image bytes
const render = new SheetRender(worksheet, imageOpts);
const imgBytes = render.toImage(0);
// Create blob and download link for each rendered image
const blob = new Blob([imgBytes], { type: 'image/png' });
const url = URL.createObjectURL(blob);
const link = document.createElement('a');
const sheetNameSafe = worksheet.name ? worksheet.name.replace(/[\/\\:?*"<>|]/g, '_') : `sheet${i+1}`;
link.href = url;
link.download = `outputCustomFilteringPerWorksheet_${sheetNameSafe}.png`;
link.textContent = `Download ${link.download}`;
downloadList.appendChild(link);
}
resultDiv.innerHTML = `<p style="color: green;">Rendered ${sheetCount} worksheet(s). Download links are available below.</p>`;
});
</script>
</html>