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Data Processing

The "Common Spreadsheet Format" is a simple object representation of the core concepts of a workbook. The utility functions work with the object representation and are intended to handle common use cases.

The Data Input and Data Output sections cover how to read from data sources and write to data sources.




Worksheet names are case-sensitive.

List the Worksheet names in tab order

var wsnames = workbook.SheetNames;

The SheetNames property of the workbook object is a list of the worksheet names in "tab order". API functions will look at this array.

Access a Worksheet by name

var worksheet = workbook.Sheets[sheet_name];

The workbook object's Sheets property is an object whose keys are sheet names and whose values are worksheet objects.

Access the first Worksheet

var first_ws = workbook.Sheets[workbook.SheetNames[0]];

Combining the previous examples, workbook.Sheets[workbook.SheetNames[0]] is the first worksheet if it exists in the workbook.

Replace a Worksheet in place

workbook.Sheets[sheet_name] = new_worksheet;

The Sheets property of the workbook object is an object whose keys are names and whose values are worksheet objects. By reassigning to a property of the Sheets object, the worksheet object can be changed without disrupting the rest of the worksheet structure.

Append a Worksheet to a Workbook

XLSX.utils.book_append_sheet(workbook, worksheet, sheet_name);

The book_append_sheet utility function appends a worksheet to the workbook. The third argument specifies the desired worksheet name. Multiple worksheets can be added to a workbook by calling the function multiple times. If the worksheet name is already used in the workbook, it will throw an error.

Append a Worksheet to a Workbook and find a unique name

var new_name = XLSX.utils.book_append_sheet(workbook, worksheet, name, true);

If the fourth argument is true, the function will start with the specified worksheet name. If the sheet name exists in the workbook, a new worksheet name will be chosen by finding the name stem and incrementing the counter:

XLSX.utils.book_append_sheet(workbook, sheetA, "Sheet2", true); // Sheet2
XLSX.utils.book_append_sheet(workbook, sheetB, "Sheet2", true); // Sheet3
XLSX.utils.book_append_sheet(workbook, sheetC, "Sheet2", true); // Sheet4
XLSX.utils.book_append_sheet(workbook, sheetD, "Sheet2", true); // Sheet5


var ws_name = "SheetJS";

/* Create worksheet */
var ws_data = [
[ "S", "h", "e", "e", "t", "J", "S" ],
[ 1 , 2 , 3 , 4 , 5 ]
var ws = XLSX.utils.aoa_to_sheet(ws_data);

/* Create workbook */
var wb = XLSX.utils.book_new();

/* Add the worksheet to the workbook */
XLSX.utils.book_append_sheet(wb, ws, ws_name);

/* Write to file */
XLSX.writeFile(wb, "SheetJS.xlsx");

Other Properties

Add a Defined Name

if(!workbook.Workbook) workbook.Workbook = {};
if(!workbook.Workbook.Names) workbook.Workbook.Names = [];
Name: "SourceData",
Ref: "Sheet1!$A$1:$D$12"

This is described in more detail in "Defined Names".

Set Workbook Properties

if(!wb.Props) wb.Props = {};
wb.Props["Company"] = "SheetJS LLC";

The full set of property names, and their mapping to the Excel UI, is included in "File Properties"



Modify a single cell value in a Worksheet

XLSX.utils.sheet_add_aoa(worksheet, [[new_value]], { origin: address });

Modify multiple cell values in a Worksheet

XLSX.utils.sheet_add_aoa(worksheet, aoa, opts);

The sheet_add_aoa utility function modifies cell values in a worksheet. The first argument is the worksheet object. The second argument is an array of arrays of values. The origin key of the third argument controls where cells will be written. The following snippet sets B3=1 and E5="abc":

XLSX.utils.sheet_add_aoa(worksheet, [
[1], // <-- Write 1 to cell B3
, // <-- Do nothing in row 4
[/*B5*/, /*C5*/, /*D5*/, "abc"] // <-- Write "abc" to cell E5
], { origin: "B3" });

"Array of Arrays Input" describes the function and the optional opts argument in more detail.


The special origin value -1 instructs sheet_add_aoa to start in column A of the row after the last row in the range, appending the data:

XLSX.utils.sheet_add_aoa(worksheet, [
["first row after data", 1],
["second row after data", 2]
], { origin: -1 });

Other Properties

Merge a group of cells

if(!worksheet["!merges"]) worksheet["!merges"] = [];

The !merges property of a worksheet object is a list of Cell Ranges. The data for the cell will be taken from the top-left cell.

A range can be created with decode_range or specified manually:

s: { r: 2, c: 1 }, // s ("start"): c = 1 r = 2 -> "B3"
e: { r: 3, c: 4 } // e ("end"): c = 4 r = 3 -> "E4"

This approach does not verify if two merged ranges intersect.