In enterprise HR scenarios, batch contract generation is one of the most common document processing needs — monthly new employee onboarding, contract renewals, labor agreement changes often involve processing dozens or even hundreds of contracts at once. Each contract needs personalized information such as employee name, position, salary, and contract term.

Comparison with Traditional SDK API Processing

This article introduces how to use Spire.Agent.Office Word AI capabilities to automatically write Excel employee data into Word templates and generate contracts in PDF format in batches, using both mail merge and placeholder replacement approaches. You are also free to save as DOCX, DOC, HTML, OFD, Markdown, XPS, and other formats to meet different archiving needs.

• Mail Merge Approach
• Placeholder Replacement Approach

For product installation and SpireToken configuration, please refer to Integrating Spire.Agent.Office in a .NET Project. The following examples assume Spire.Agent.Office is already installed and SpireToken is configured.

Mail Merge Approach

Mail merge is the standard solution for batch Word document generation and the most commonly used pattern in HR scenarios. The core idea is: a contract template Word document with merge fields and a data source, letting AI complete the data-to-template merge.

using Spire.Agent.Office.AI;
using Spire.Agent.Office.Extensions;
using Spire.Doc;

// Multiple document paths (data source files)
string[] attachmentPaths = new string[] { @"E:\data.xlsx" };

// Word template file path
string inputPath = @"E:\template-mailmerge.docx";  
// Result document path (null here — will use the output folder path set below)
string savePath = null;  
// Output directory
string OutDir = @"E:\output";  
// SpireToken Key
string key = "**************************";  
// Natural language instruction
string instruction =
      "Execute mail merge: populate employee data from the attachment 'data.xlsx' into the merge fields of the contract template row by row; " +
      "preserve the original document layout and styling after merging; " +
      "generate one independent contract document per employee and save the output in PDF format"; 

// Call the Word document processing function
AIResult result = ExecuteDemoWord(instruction, inputPath, savePath, key, OutDir, attachmentPaths);

// Record processing log
WriteLog(result, "word", @"E:\log\");


// Execute Word document AI processing
static AIResult ExecuteDemoWord(string instruction, string inputPath, string savePath, string key, string output, string[] attachmentPaths)
{
    // Create AIOptions configuration object
    AIOptions options = new AIOptions();
    // Set working directory to output directory
    options.WorkDir = output; 
    // Set SpireToken Key
    options.SpireToken = key;  

    // Use Document object to process Word document
    using (Document doc = new Document())
    {
        // Load Word template from file
        if (!string.IsNullOrEmpty(inputPath) && File.Exists(inputPath))
        {
            doc.LoadFromFile(inputPath);  
        }
        // Create AI document processor
        AIDocumentProcessor processor = doc.AI(options);
    
        // Execute AI instruction
        return processor.ExecuteInstruction(doc, instruction, savePath, attachmentPaths);
    }
}

Original Word template (with mail merge fields) and Excel data Output generated via mail merge

Each generated contract fully preserves the template's formatting, table styles, and font settings, with all merge fields replaced by the corresponding employee data. If 50 new employees are being onboarded, just one template + one Excel file + one instruction is all it takes to generate all contracts.

Placeholder Replacement Approach

The placeholder replacement approach does not require predefining mail merge fields in the template. Instead, it uses custom placeholder markers (such as {{Name}}, {{Salary}}) directly in the document, which the AI agent identifies and replaces.

// Multiple document paths (data source files)
string[] attachmentPaths = new string[] { @"E:\data.xlsx" };

// Contract template file path
string inputPath = @"E:\template.docx";  
// Save path (null here — will use the output folder path set below)
string savePath = null;  
// Output directory
string OutDir = @"E:\output"; 
// SpireToken Key
string key = "**************************";  

// Natural language instruction
string instruction =
    "Read employee data from 'data.xlsx' and replace the corresponding placeholders in the contract template row by row" +  
    "Highlight the replaced field content, preserve the original document layout, styling, and fonts after replacement," +  
    "Generate one independent contract document per employee and save the output in PDF format"; 

// Call the AI Word document processing method
AIResult result = ExecuteDemoWord1(instruction, inputPath, savePath, key, OutDir, attachmentPaths);

// Record processing log
WriteLog(result, "word", @"E:\log\");


// Execute Word document AI processing
static AIResult ExecuteDemoWord(string instruction, string inputPath, string savePath, string key, string output, string[] attachmentPaths)
{
    // Create AIOptions configuration object
    AIOptions options = new AIOptions();
    // Set working directory to output directory
    options.WorkDir = output;  
    // Set SpireToken Key
    options.SpireToken = key; 

    // Use Document object to process Word document
    using (Document doc = new Document())
    {
        // Load Word template from file
        if (!string.IsNullOrEmpty(inputPath) && File.Exists(inputPath))
        {
            doc.LoadFromFile(inputPath);  
        }
        // Create AI document processor
        AIDocumentProcessor processor = doc.AI(options);
    
        // Execute AI instruction
        return processor.ExecuteInstruction(doc, instruction, savePath, attachmentPaths);
    }
}

Original Word template (with {{}} placeholders) and Excel data Output generated via placeholder replacement

Two Approaches Compared

For creating Word templates with Spire.Agent.Office, please refer to the article "Creating Various Word Templates with Spire.Agent.Office".

Frequently Asked Questions

Generated document style changed

Cause: The AI model may modify or add content during processing.

Solution: Add a description like "preserve the original document layout, styling, and fonts" to the instruction.

Number of generated documents does not match the number of data rows after mail merge

Cause: Empty rows or merged cells in the data source Excel file, causing inaccurate row counting.

Solution: Ensure the first row of the data source contains column headers, with each subsequent row corresponding to one employee record and no empty rows in between. If the issue persists, add a sequence number column to the data source for validation.

Obtaining a SpireToken Key

• Contact sales@e-iceblue.com or visit https://www.e-iceblue.com/TemLicense.html to obtain a trial or commercial API key.

Configure it in code:

AIOptions options = new AIOptions();
options.SpireToken = key;

Traditional Spire.Office for .NET workflows often require developers to have in-depth API knowledge and write extensive boilerplate code for tasks like formatting, extraction, and conversion. Spire.Agent.Office introduces an AI layer that abstracts this complexity, enabling you to accomplish these tasks using plain natural language instructions.

This tutorial walks you through integrating Spire.Agent.Office into a .NET 10 project, enabling natural-language-powered document processing with minimal code.

• Why Choose Spire.Agent.Office
• Project Setup and Library Reference
• AI-Powered Document Processing
• Frequently Asked Questions
• Apply for SpireToken Key

Why Choose Spire.Agent.Office

Spire.Agent.Office is an AI agent built on top of the traditional Spire.Office for .NET document engine. The core differences are:

How It Works

Natural Language Instruction → Spire.Agent.Office AI Layer → Spire.Office Document Engine → Output File

Spire.Agent.Office parses your natural language instructions, converts them into internal calls to the Spire.Office document engine for processing, and ultimately generates the desired document. It supports processing and conversion of Word, Excel, PowerPoint, PDF, and other document formats.

Core Advantages

Typical Use Cases

• Automated internal report generation and formatting
• Batch contract processing and data extraction
• Intelligent multi-format document conversion and distribution
• Automated meeting slide layout and export

Project Setup and Library Reference

Creating a .NET 10 Project

Installing Spire.Agent.Office via NuGet

After installing Spire.Agent.Office via NuGet, dependencies are installed automatically.

Importing Spire.Agent.Office Assemblies Locally

Download Spire.Agent.Office from the website, extract it to a local directory, and import it into the project.

When adding via local DLLs, the following dependencies are also required for optimal performance:

AI-Powered Document Processing

Core Workflow

Document AI processing follows this pattern:

1. Create a document object (Workbook / Document / PdfDocument / Presentation)
2. Load a preset document (optional; can start with an empty document)
3. Configure AIOptions (set SpireToken)
4. Call .AI(options) to obtain an AIDocumentProcessor
5. Execute AI instructions and monitor execution status:
   • Processing existing documents: Call AIDocumentProcessor.ExecuteInstruction(), returns AIResult
   • Generating PPT documents: Call AIDocumentProcessor.GeneratePresentation(), returns GenerationResult

Core Code

using Spire.Agent.Office.AI;
using Spire.Agent.Office.Extensions;
using Spire.Pdf;
using Spire.Doc;
using Spire.Presentation;
using Spire.Xls;

// Excel Processing
static AIResult ExecuteDemoXls(string instruction, string inputPath, string savePath, string key, string[] attachmentPaths)
{
    AIOptions options = new AIOptions();
    options.SpireToken = key;

    using (Workbook workbook = new Workbook())
    {
        // Load the document if the input path exists and the file is accessible
        if (!string.IsNullOrEmpty(inputPath) && File.Exists(inputPath))
        {
            workbook.LoadFromFile(inputPath);
        }
        // Otherwise, use an empty Workbook
        AIDocumentProcessor processor = workbook.AI(options);
        return processor.ExecuteInstruction(workbook, instruction, savePath, attachmentPaths);
    }
}

// Word Processing
static AIResult ExecuteDemoWord(string instruction, string inputPath, string savePath, string key, string[] attachmentPaths)
{
    AIOptions options = new AIOptions();
    options.SpireToken = key;

    using (Document doc = new Document())
    {
        // Load the document if the input path exists and the file is accessible
        if (!string.IsNullOrEmpty(inputPath) && File.Exists(inputPath))
        {
            doc.LoadFromFile(inputPath);
        }
        // Otherwise, use an empty Document
        AIDocumentProcessor processor = doc.AI(options);
        return processor.ExecuteInstruction(doc, instruction, savePath, attachmentPaths);
    }
}

// PDF Processing
static AIResult ExecuteDemoPDF(string instruction, string inputPath, string savePath, string key, string[] attachmentPaths)
{
    AIOptions options = new AIOptions();
    options.SpireToken = key;

    using (PdfDocument pdf = new PdfDocument())
    {
        // Load the document if the input path exists and the file is accessible
        if (!string.IsNullOrEmpty(inputPath) && File.Exists(inputPath))
        {
            pdf.LoadFromFile(inputPath);
        }
        // Otherwise, use an empty PdfDocument
        AIDocumentProcessor processor = pdf.AI(options);
        return processor.ExecuteInstruction(pdf, instruction, savePath, attachmentPaths);
    }
}

// PPT Generation
static PPTGenerationResult GeneratPPT(string input, string instruction, string savePath, string key)
{
    AIOptions options = new AIOptions();
    options.SpireToken = key;

    using (Presentation ppt = new Presentation())
    {
        AIDocumentProcessor processor = ppt.AI(options);
        return processor.GeneratePresentation(input, instruction, savePath);
    }
}

// Based on existing PPT processing
static AIResult ExecuteDemoPPT(string inputPath, string instruction, string savePath, string key, string[] attachmentPaths)
{
    AIOptions options = new AIOptions();
    options.SpireToken = key;

    using (Presentation ppt = new Presentation())
    {
        // Load the document if the input path exists and the file is accessible
        if (!string.IsNullOrEmpty(inputPath) && File.Exists(inputPath))
        {
            ppt.LoadFromFile(inputPath);
        }
        // Otherwise, use an empty Presentation
        AIDocumentProcessor processor = ppt.AI(options);
        return processor.ExecuteInstruction(ppt, instruction, savePath, attachmentPaths);
    }
}

// Write execution log
static void WriteLog(dynamic? aiResult, string taskName, string basePath)
{
    string logFilePath = Path.Combine(basePath, $"{taskName}.txt");
    string? logDir = Path.GetDirectoryName(logFilePath);
    if (!string.IsNullOrEmpty(logDir) && !Directory.Exists(logDir))
        Directory.CreateDirectory(logDir);

    var logBuilder = new System.Text.StringBuilder();

    // Determine execution status: Success/Failure/Skipped
    string status = aiResult == null ? "SKIPPED" :
        aiResult.Success ? "SUCCESS" : $"FAILED: {aiResult.ErrorMessage}";

    logBuilder.AppendLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss}] [{taskName}] {status}");

    if (aiResult != null)
    {
        // Log execution duration
        logBuilder.AppendLine($" | Duration: {aiResult.Duration.TotalSeconds:F2}s");

        // Log token usage statistics
        var tu = aiResult.TokenUsage;
        if (tu != null)
        {
            logBuilder.Append($" | In: {tu.InputTokens:N0}");           // Input tokens
            logBuilder.Append($" | Out: {tu.OutputTokens:N0}");         // Output tokens
            logBuilder.Append($" | CacheR: {tu.CacheReadTokens:N0}");   // Cache read tokens
            logBuilder.Append($" | CacheW: {tu.CacheWriteTokens:N0}");  // Cache write tokens
            logBuilder.Append($" | CacheT: {tu.TotalCacheTokens:N0}");  // Total cache tokens
            logBuilder.Append($" | Total: {tu.TotalTokens:N0}");        // Total tokens
        }
    }

    logBuilder.AppendLine();
    File.AppendAllText(logFilePath, logBuilder.ToString());
}

Calling AI Processing

The following examples demonstrate using natural language interaction to leverage the system's powerful document processing capabilities for various complex document tasks.

// Multiple document paths
string[] attachmentPaths = new string[] { };

// Word Processing
string inputPath = @"in.docx";
string savePath = @"out.pdf";
string key = "SpireToken key";
string instruction = "Find '****' and highlight it, save result to PDF";
AIResult result = ExecuteDemoWord(instruction, inputPath, savePath, key, attachmentPaths);
WriteLog(result, "word", @"log\");

// PPT Processing
string inputPath = @"in.pptx";
string savePath = @"out.pptx";
string key = "SpireToken key";
string instruction = "Add notes description to each slide";
AIResult result = ExecuteDemoPPT(instruction, inputPath, savePath, key, attachmentPaths);
WriteLog(result, "ppt", @"log\");

// PPT Generation
string inputPath = @"AI.md";
string savePath = @"out.pptx";
string key = "SpireToken key";
string instruction = "Generate a PPT based on AI.md";
PPTGenerationResult result = GeneratPPT(inputPath, instruction, savePath, key);
WriteLog(result, "ppt", @"log\");

// PDF Processing
string inputPath = @"in.pdf";
string savePath = @"out.md";
string key = "SpireToken key";
string instruction = "Extract table data and save as standard markdown format";
AIResult result = ExecuteDemoPDF(instruction, inputPath, savePath, key, attachmentPaths);
WriteLog(result, "pdf", @"log\");

// Excel Processing
string inputPath = @"in.xlsx";
string savePath = @"out.pdf";
string key = "SpireToken key";
string instruction = "Delete empty rows in the document";
AIResult result = ExecuteDemoXls(instruction, inputPath, savePath, key, attachmentPaths);
WriteLog(result, "xls", @"log\");

Frequently Asked Questions

SpireToken Key Not Configured Properly

If the SpireToken Key is not configured, is incorrect, or has expired, Spire.Agent.Office will throw an exception and the program will abort. Ensure the SpireToken Key is valid before proceeding.

AI Instruction Execution Failed

The AIResult returned by ExecuteInstruction may contain failure information. Check the Success property.

AIResult result = processor.ExecuteInstruction(doc, instruction, outputPath);

if (result == null || !result.Success)
{
    throw new InvalidOperationException(
        $"AI instruction failed: {result?.ErrorMessage ?? "Unknown error"}");
}

Incorrect Document Path

If processing an existing document, an incorrect file path will cause document loading to fail:

• Ensure the document path is correct
• For multi-document operations (e.g., document merging), additional documents can be defined in attachmentPaths

Apply for SpireToken Key

Spire.Agent.Office requires a valid SpireToken Key to experience full functionality:

• Contact sales@e-iceblue.com or visit https://www.e-iceblue.com/TemLicense.html to obtain a trial or commercial API key

Configure it in your code:

AIOptions options = new AIOptions();
options.SpireToken = key;

Copying worksheets is one of the most common and efficient operations in everyday Excel document processing — whether you are quickly creating similar reports from a template or consolidating data across multiple documents. Spire.XLS for JavaScript handles this entirely in the browser via WebAssembly, using a virtual file system (VFS) to manage input and output files — no backend server required.

This article covers three core features:

• Copy a worksheet within the same workbook
• Copy a worksheet across workbooks
• Copy a selected cell range

For installation and project setup, refer to Integrating Spire.XLS for JavaScript in a React Project. The examples below assume Spire.XLS is installed and the WebAssembly module is initialized.

Copy a Worksheet Within the Same Workbook

Duplicating a worksheet within the same workbook is a frequent development task — for example, quickly creating next month's report copy from a monthly template. Spire.XLS for JavaScript provides the CopyFrom method to duplicate a worksheet. The copied sheet retains all content from the source worksheet, including data, styles, fonts, colors, borders, column widths, and row heights.

function App() {
  const sheetToSVG = async () => {
    // Get the Spire.XLS WASM module
    const xlsModule = window.wasmModule?.spirexls;

    // Check if the module is ready
    if (!xlsModule) {
      alert('Spire.Xls is not ready yet');
      return;
    }

    // Load fonts and the Excel file into VFS
    await window.spire.FetchFileToVFS('ARIAL.TTF', '/Library/Fonts/', `${process.env.PUBLIC_URL}/font/`);
    const inputFileName = 'Sample.xlsx';
    await window.spire.FetchFileToVFS(inputFileName, '', `${process.env.PUBLIC_URL}data/`);

    // Load the workbook
    const workbook = new xlsModule.Workbook();
    workbook.LoadFromFile({ fileName: inputFileName });

    // Get the first worksheet
    let sheet = workbook.Worksheets.get(0);

    // Add a new worksheet
    let sheet1 = workbook.Worksheets.Add("MySheet");

    // Copy the first worksheet into the newly added sheet
    sheet1.CopyFrom(sheet);

    const outputFileName = "CopySheetWithinWorkbook_output.xlsx";
    workbook.SaveToFile({ fileName: outputFileName });

    // Release the workbook object to free resources
    workbook.Dispose();

    // Read the converted file from VFS and trigger download
    const fileArray = window.dotnetRuntime.Module.FS.readFile(outputFileName);
    const blob = new Blob([fileArray], { type: "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" });
    const url = URL.createObjectURL(blob);
    const a = document.createElement('a');
    a.href = url;
    a.download = outputFileName;
    a.click();
    URL.revokeObjectURL(url);
  };

  return (
    <div style={{ textAlign: 'center', height: '300px' }}>
      <h1>Copy Worksheet Within Workbook</h1>
      <button onClick={sheetToSVG}>
        Start
      </button>
    </div>
  );
}

export default App;

When using CopyFrom, data, styles, fonts, colors, borders, and column widths from the source worksheet are fully preserved in the new sheet.

Copy a Worksheet Across Workbooks

In real-world scenarios, data from multiple Excel files often needs to be consolidated into a single workbook — for example, extracting specific sheets from departmental reports and merging them into a master sheet. The AddCopy method lets you copy a worksheet from the source workbook into the target workbook with all its content intact.

function App() {
  const sheetToSVG = async () => {
    // Get the Spire.XLS WASM module
    const xlsModule = window.wasmModule?.spirexls;

    // Check if the module is ready
    if (!xlsModule) {
      alert('Spire.Xls is not ready yet');
      return;
    }

    // Load fonts and the Excel files into VFS
    await window.spire.FetchFileToVFS('arial.ttf', '/Library/Fonts/', `${process.env.PUBLIC_URL}/font/`);
    const sourceFileName = 'ReadImages.xlsx';
    const targetFileName = 'Sample.xlsx';
    await window.spire.FetchFileToVFS(sourceFileName, '', `${process.env.PUBLIC_URL}data/`);
    await window.spire.FetchFileToVFS(targetFileName, '', `${process.env.PUBLIC_URL}data/`);

    // Load the source workbook
    const sourceWorkbook = new xlsModule.Workbook();
    sourceWorkbook.LoadFromFile({ fileName: sourceFileName });

    // Get the first worksheet of the source workbook
    const srcWorksheet = sourceWorkbook.Worksheets.get(0);

    // Load the target workbook
    const targetWorkbook = new xlsModule.Workbook();
    targetWorkbook.LoadFromFile({ fileName: targetFileName });

    // Add a new worksheet in the target workbook and copy the source sheet into it
    targetWorkbook.Worksheets.AddCopy({ sheet: srcWorksheet });

    // Save the target workbook
    const outputFileName = "CopyAcrossWorkbooks_output.xlsx";
    targetWorkbook.SaveToFile({ fileName: outputFileName });

    // Release resources
    sourceWorkbook.Dispose();
    targetWorkbook.Dispose();

    // Read the converted file from VFS and trigger download
    const fileArray = window.dotnetRuntime.Module.FS.readFile(outputFileName);
    const blob = new Blob([fileArray], { type: "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"});
    const url = URL.createObjectURL(blob);
    const a = document.createElement('a');
    a.href = url;
    a.download = outputFileName;
    a.click();
    URL.revokeObjectURL(url);
  };

  return (
    <div style={{ textAlign: 'center', height: '300px' }}>
      <h1>Copy Worksheet Across Workbooks</h1>
      <button onClick={sheetToSVG}>
        Start
      </button>
    </div>
  );
}

export default App;

When copying across workbooks, all data and styles from the source worksheet are preserved — AddCopy copies the complete worksheet content into the target workbook.

Copy a Selected Cell Range

Sometimes you do not need to copy an entire worksheet — you only need to copy a specific cell range (such as a particular data table or summary result) to a target location. Spire.XLS for JavaScript provides the Copy method, which copies data, styles, and formatting from the source range to the starting position of the target range.

function App() {
  const sheetToSVG = async () => {
    // Get the Spire.XLS WASM module
    const xlsModule = window.wasmModule?.spirexls;

    // Check if the module is ready
    if (!xlsModule) {
      alert('Spire.Xls is not ready yet');
      return;
    }

    // Load the source Excel file into VFS
    await window.spire.FetchFileToVFS('ARIAL.TTF', '/Library/Fonts/', `${process.env.PUBLIC_URL}/font/`);
    const inputFileName = 'Sample.xlsx';
    await window.spire.FetchFileToVFS(inputFileName, '', `${process.env.PUBLIC_URL}data/`);

    // Load the workbook
    const workbook = new xlsModule.Workbook();
    workbook.LoadFromFile({ fileName: inputFileName });

    // Get the first row of the first worksheet as the source range
    const sheet = workbook.Worksheets.get(0);
    const sourceRange = sheet.Range.get("A1:E1");

    // Add a new worksheet
    let sheet1 = workbook.Worksheets.Add("AddSheet");

    // Copy the source range to the starting position of the target worksheet
    sheet.Copy(sourceRange, sheet1, sheet.FirstRow, sheet.FirstColumn, true);

    // Save the workbook
    const outputFileName = "CopyRange_output22.xlsx";
    workbook.SaveToFile({ fileName: outputFileName });

    // Release resources
    workbook.Dispose();

    // Read the converted file from VFS and trigger download
    const fileArray = window.dotnetRuntime.Module.FS.readFile(outputFileName);
    const blob = new Blob([fileArray], { type: "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" });
    const url = URL.createObjectURL(blob);
    const a = document.createElement('a');
    a.href = url;
    a.download = outputFileName;
    a.click();
    URL.revokeObjectURL(url);
  };

  return (
    <div style={{ textAlign: 'center', height: '300px' }}>
      <h1>Copy Range</h1>
      <button onClick={sheetToSVG}>
        Start
      </button>
    </div>
  );
}

export default App;

The Copy method transfers data, styles, and formatting from the source range to the target range — ideal for lightweight scenarios where only partial data extraction is needed.

FAQ

Column width differs after copying

Cause: Font mismatch between the source and target workbooks.

Solution: Ensure all required font files are loaded into the VFS environment of the target workbook before copying across workbooks:

await window.spire.FetchFileToVFS(
  'arial.ttf', '/Library/Fonts/', '/'
);

Range content is pasted at the wrong position

Cause: Incorrect destRow and destColumn parameters in the Copy method, causing data to be pasted at an unexpected location.

Solution: Confirm that the destination row and column indices start from 1 (not 0), and verify the row and column range of the target worksheet before copying.

Get a Free License

Spire.XLS for JavaScript offers a 30-day full-featured free trial license with no functional limitations. Apply here to evaluate before purchasing.

Managing worksheets — adding, removing, and reordering them — is one of the most fundamental and frequently used operations in Excel document processing. Spire.XLS for JavaScript handles these operations entirely in the browser via WebAssembly, using a virtual file system (VFS) to manage input and output files — no backend server required.

This article covers three core features:

• Add worksheet
• Remove worksheet
• Move and reorder worksheets

For installation and project setup, refer to Integrating Spire.XLS for JavaScript in a React Project. The examples below assume Spire.XLS is installed and the WebAssembly module is initialized.

Add Worksheet

Adding new worksheets to a workbook is a common requirement in daily development. Spire.XLS for JavaScript provides the Add method to create a new worksheet and give it a name. After adding, you can write data to the new sheet's cells and save the workbook.

function App() {
  const startProcessing = async () => {
    // Get the Spire.XLS WASM module
    const xlsModule = window.wasmModule?.spirexls;
    if (!xlsModule) {
      alert('Spire.Xls is not ready yet');
      return;
    }

    // Load fonts and the Excel file into VFS
    await window.spire.FetchFileToVFS('ARIAL.TTF', '/Library/Fonts/', `${process.env.PUBLIC_URL}/font/`);
    const inputFileName = 'AddWorksheet.xlsx';
    await window.spire.FetchFileToVFS(inputFileName, '', `${process.env.PUBLIC_URL}/data/`);

    // Create a workbook instance and load the file
    const workbook = new xlsModule.Workbook();
    workbook.LoadFromFile({ fileName: inputFileName });

    // Add a new worksheet named "NewSheet"
    const sheet = workbook.Worksheets.Add("NewSheet");
    sheet.Range.get("C5").Text = "This is an inserted sheet.";

    // Auto-fit columns
    sheet.AllocatedRange.AutoFitColumns();

    // Save the workbook
    const outputFileName = "AddWorksheet_output.xlsx";
    workbook.SaveToFile({ fileName: outputFileName });

    // Release resources
    workbook.Dispose();

    // Read the output file from VFS, wrap it as a Blob, and trigger download
    const modifiedFileArray = window.dotnetRuntime.Module.FS.readFile(outputFileName);
    const blob = new Blob([modifiedFileArray], { type: "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" });
    const url = URL.createObjectURL(blob);
    const a = document.createElement('a');
    a.href = url;
    a.download = outputFileName;
    a.click();
    URL.revokeObjectURL(url);
  };

  return (
    <div style={{ textAlign: 'center', height: '300px' }}>
      <h1>Add Worksheet</h1>
      <button onClick={startProcessing}>
        Start
      </button>
    </div>
  );
}

export default App;

Adding a new worksheet after the existing ones via the Add method.

Remove Worksheet

When you need to clean up unwanted worksheets from a workbook, you can remove them directly by name. Spire.XLS for JavaScript's Remove method precisely locates and removes the target worksheet.

function App() {
  const startProcessing = async () => {
    // Get the Spire.XLS WASM module
    const xlsModule = window.wasmModule?.spirexls;
    if (!xlsModule) {
      alert('Spire.Xls is not ready yet');
      return;
    }

    // Load fonts and the Excel file into VFS
    await window.spire.FetchFileToVFS('ARIAL.TTF', '/Library/Fonts/', `${process.env.PUBLIC_URL}/font/`);
    const inputFileName = 'RemoveWorksheet.xlsx';
    await window.spire.FetchFileToVFS(inputFileName, '', `${process.env.PUBLIC_URL}/data/`);

    // Create a workbook instance and load the file
    const workbook = new xlsModule.Workbook();
    workbook.LoadFromFile({ fileName: inputFileName });

    // Remove a worksheet by name
    const sheet = workbook.Worksheets.get("Sheet2");
    workbook.Worksheets.Remove(sheet);
    // Remove by index
    //workbook.Worksheets.RemoveAt(1);

    // Save the workbook
    const outputFileName = "RemoveWorksheet_output.xlsx";
    workbook.SaveToFile({ fileName: outputFileName });

    // Release resources
    workbook.Dispose();

    // Read the output file from VFS, wrap it as a Blob, and trigger download
    const modifiedFileArray = window.dotnetRuntime.Module.FS.readFile(outputFileName);
    const blob = new Blob([modifiedFileArray], { type: "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" });
    const url = URL.createObjectURL(blob);
    const a = document.createElement('a');
    a.href = url;
    a.download = outputFileName;
    a.click();
    URL.revokeObjectURL(url);
  };

  return (
    <div style={{ textAlign: 'center', height: '300px' }}>
      <h1>Remove Worksheet</h1>
      <button onClick={startProcessing}>
        Start
      </button>
    </div>
  );
}

export default App;

Using Remove to delete a worksheet by name.

Move and Reorder Worksheets

Reordering worksheets is a common task when organizing an Excel document. With Spire.XLS for JavaScript's MoveWorksheet method, you can move a worksheet to a target index position, effectively reordering the sheets within the workbook.

function App() {
  const startProcessing = async () => {
    // Get the Spire.XLS WASM module
    const xlsModule = window.wasmModule?.spirexls;
    if (!xlsModule) {
      alert('Spire.Xls is not ready yet');
      return;
    }

    // Load fonts and the Excel file into VFS
    await window.spire.FetchFileToVFS('ARIAL.TTF', '/Library/Fonts/', `${process.env.PUBLIC_URL}/font/`);
    const inputFileName = 'Sample.xlsx';
    await window.spire.FetchFileToVFS(inputFileName, '', `${process.env.PUBLIC_URL}/data/`);

    // Create a workbook instance and load the file
    const workbook = new xlsModule.Workbook();
    workbook.LoadFromFile({ fileName: inputFileName });

    // Get the first worksheet and move it to index 1
    const sheet = workbook.Worksheets.get(0);
    sheet.MoveWorksheet(1);

    // Save the workbook
    const outputFileName = "MoveWorksheet_output.xlsx";
    workbook.SaveToFile({ fileName: outputFileName });

    // Release resources
    workbook.Dispose();

    // Read the output file from VFS, wrap it as a Blob, and trigger download
    const modifiedFileArray = window.dotnetRuntime.Module.FS.readFile(outputFileName);
    const blob = new Blob([modifiedFileArray], { type: "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" });
    const url = URL.createObjectURL(blob);
    const a = document.createElement('a');
    a.href = url;
    a.download = outputFileName;
    a.click();
    URL.revokeObjectURL(url);
  };

  return (
    <div style={{ textAlign: 'center', height: '300px' }}>
      <h1>Move Worksheet</h1>
      <button onClick={startProcessing}>
        Start
      </button>
    </div>
  );
}

export default App;

Moving the first worksheet to the second sheet position via the MoveWorksheet method.

FAQ

Index out of range when operating on worksheets

Cause: The index parameter is outside the range of the current worksheet collection in the workbook.

Solution: Verify the total number of worksheets before performing the operation, ensuring the index is within 0 to worksheets.Count-1. Use workbook.Worksheets.Count to get the current total:

const count = workbook.Worksheets.Count;

Worksheet not found when removing by name

Cause: The specified worksheet name does not exactly match the actual name in the workbook.

Solution: Iterate through the worksheet names to confirm before removal:

for (let i = 0; i < workbook.Worksheets.Count; i++) {
  let name = workbook.Worksheets.get(i).Name;
  console.log(name);
}

Get a Free License

Spire.XLS for JavaScript offers a 30-day full-featured free trial license with no functional limitations. Apply here to evaluate before purchasing.