docs.sheetjs.com/docz/docs/08-api/09-utilities.md

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9

Utility Functions

The sheet_to_* functions accept a worksheet and an optional options object.

The *_to_sheet functions accept a data object and an optional options object.

The sheet_add_* functions accept worksheet, data, and optional options.

The examples are based on the following worksheet:

S	h	e	e	t	J	S
1	2			5	6	7
2	3			6	7	8
3	4			7	8	9
4	5	6	7	8	9	0

Array of Arrays Input

Create a worksheet from an array of arrays

var ws = XLSX.utils.aoa_to_sheet(aoa, opts);

XLSX.utils.aoa_to_sheet takes an array of arrays of JS values and returns a worksheet resembling the input data. Numbers, Booleans and Strings are stored as the corresponding styles. Dates are stored as date or numbers. Array holes and explicit undefined values are skipped. null values may be stubbed. All other values are stored as strings. The function takes an options argument:

Option Name	Default	Description
dateNF	FMT 14	Use specified date format in string output
cellDates	false	Store dates as type d (default is n)
sheetStubs	false	Create cell objects of type z for null values
nullError	false	If true, emit #NULL! error cells for null values

The example worksheet can be generated with:

var ws = XLSX.utils.aoa_to_sheet([
  ["S", "h", "e", "e", "t", "J", "S"],
  [  1,   2,    ,    ,   5,   6,   7],
  [  2,   3,    ,    ,   6,   7,   8],
  [  3,   4,    ,    ,   7,   8,   9],
  [  4,   5,   6,   7,   8,   9,   0]
]);

Add data from an array of arrays to an existing worksheet

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

XLSX.utils.sheet_add_aoa takes an array of arrays of JS values and updates an existing worksheet object. It follows the same process as aoa_to_sheet and accepts an options argument:

Option Name	Default	Description
dateNF	FMT 14	Use specified date format in string output
cellDates	false	Store dates as type d (default is n)
sheetStubs	false	Create cell objects of type z for null values
nullError	false	If true, emit #NULL! error cells for null values
origin		Use specified cell as starting point (see below)

origin is expected to be one of:

origin	Description
(cell object)	Use specified cell (cell object)
(string)	Use specified cell (A1-style cell)
(number >= 0)	Start from the first column at specified row (0-indexed)
-1	Append to bottom of worksheet starting on first column
(default)	Start from cell A1

The example worksheet can be built up in the order A1:G1, A2:B4, E2:G4, A5:G5:

/* Initial row */
var ws = XLSX.utils.aoa_to_sheet([ "SheetJS".split("") ]);

/* Write data starting at A2 */
XLSX.utils.sheet_add_aoa(ws, [[1,2], [2,3], [3,4]], {origin: "A2"});

/* Write data starting at E2 */
XLSX.utils.sheet_add_aoa(ws, [[5,6,7], [6,7,8], [7,8,9]], {origin:{r:1, c:4}});

/* Append row */
XLSX.utils.sheet_add_aoa(ws, [[4,5,6,7,8,9,0]], {origin: -1});

Array of Objects Input

Create a worksheet from an array of objects

var ws = XLSX.utils.json_to_sheet(aoo, opts);

XLSX.utils.json_to_sheet takes an array of objects and returns a worksheet with automatically-generated "headers" based on the keys of the objects. The default column order is determined by the first appearance of the field using Object.keys. The function accepts an options argument:

Option Name	Default	Description
header		Use specified field order (default Object.keys) **
dateNF	FMT 14	Use specified date format in string output
cellDates	false	Store dates as type d (default is n)
skipHeader	false	If true, do not include header row in output
nullError	false	If true, emit #NULL! error cells for null values

:::caution

All fields from each row will be written! header hints at a particular order but is not exclusive. To remove fields from the export, filter the data source.

Some data sources have special options to filter properties. For example, MongoDB will add the _id field when finding data from a collection:

const aoo_with_id = await coll.find({}).toArray();
const ws = XLSX.utils.json_to_sheet(aoo_with_id); // includes _id column

This can be filtered out through the projection property:

const aoo = await coll.find({}, {projection:{_id:0}}).toArray(); // no _id !
const ws = XLSX.utils.json_to_sheet(aoo);

If a data source does not provide a filter option, it can be filtered manually:

const aoo = data.map(obj => Object.fromEntries(Object.entries(obj).filter(r => headers.indexOf(r[0]) > -1)));

:::

• If header is an array, missing keys will be added in order of first use.
• Cell types are deduced from the type of each value. For example, a Date object will generate a Date cell, while a string will generate a Text cell.
• Null values will be skipped by default. If nullError is true, an error cell corresponding to #NULL! will be written to the worksheet.

The example sheet cannot be reproduced using plain objects since JS object keys must be unique. After replacing the second e and S with e_1 and S_1:

var ws = XLSX.utils.json_to_sheet([
  { S:1, h:2,    ,      , t:5, J:6, S_1:7 },
  { S:2, h:3,    ,      , t:6, J:7, S_1:8 }
  { S:3, h:4,    ,      , t:7, J:8, S_1:9 }
  { S:4, h:5, e:6, e_1:7, t:8, J:9, S_1:0 }
], {header:["S","h","e","e_1","t","J","S_1"]});

Alternatively, a different set of unique headers can be used with skipHeader:

var ws = XLSX.utils.json_to_sheet([
  { A:"S", B:"h", C:"e", D:"e", E:"t", F:"J", G:"S" },
  { A:  1, B:  2,      ,      , E:  5, F:  6, G:  7  },
  { A:  2, B:  3,      ,      , E:  6, F:  7, G:  8  }
  { A:  3, B:  4,      ,      , E:  7, F:  8, G:  9  },
  { A:  4, B:  5, C:  6, D:  7, E:  8, F:  9, G:  0  },
], {header:["A","B","C","D","E","F","G"], skipHeader:true});

Add data from an array of objects to an existing worksheet

XLSX.utils.sheet_add_json(ws, aoo, opts);

XLSX.utils.sheet_add_json takes an array of objects and updates an existing worksheet object. It follows the same process as json_to_sheet and accepts an options argument:

Option Name	Default	Description
header		Use specified column order (default Object.keys)
dateNF	FMT 14	Use specified date format in string output
cellDates	false	Store dates as type d (default is n)
skipHeader	false	If true, do not include header row in output
nullError	false	If true, emit #NULL! error cells for null values
origin		Use specified cell as starting point (see below)

origin is expected to be one of:

origin	Description
(cell object)	Use specified cell (cell object)
(string)	Use specified cell (A1-style cell)
(number >= 0)	Start from the first column at specified row (0-indexed)
-1	Append to bottom of worksheet starting on first column
(default)	Start from cell A1

This example worksheet can be built up in the order A1:G1, A2:B4, E2:G4, A5:G5:

/* Initial row */
var ws = XLSX.utils.json_to_sheet([
  { A: "S", B: "h", C: "e", D: "e", E: "t", F: "J", G: "S" }
], {header: ["A", "B", "C", "D", "E", "F", "G"], skipHeader: true});

/* Write data starting at A2 */
XLSX.utils.sheet_add_json(ws, [
  { A: 1, B: 2 }, { A: 2, B: 3 }, { A: 3, B: 4 }
], {skipHeader: true, origin: "A2"});

/* Write data starting at E2 */
XLSX.utils.sheet_add_json(ws, [
  { A: 5, B: 6, C: 7 }, { A: 6, B: 7, C: 8 }, { A: 7, B: 8, C: 9 }
], {skipHeader: true, origin: { r: 1, c: 4 }, header: [ "A", "B", "C" ]});

/* Append row */
XLSX.utils.sheet_add_json(ws, [
  { A: 4, B: 5, C: 6, D: 7, E: 8, F: 9, G: 0 }
], {header: ["A", "B", "C", "D", "E", "F", "G"], skipHeader: true, origin: -1});

:::note

If the header option is an array, sheet_add_json and sheet_to_json will append missing elements.

This design enables consistent header order across calls:

function SheetJSHeaderOrder() {
  /* Use shared header */
  const header = [];
  const ws1 = XLSX.utils.json_to_sheet([ {C: 2, D: 3}, ], {header});
  XLSX.utils.sheet_add_json(ws1, [ {D: 1, C: 4}, ], {header, origin: -1, skipHeader: true});

  /* only use header in first call */
  const ws2 = XLSX.utils.json_to_sheet([ {C: 2, D: 3}, ], {header:[]});
  XLSX.utils.sheet_add_json(ws2, [ {D: 1, C: 4}, ], {origin: -1, skipHeader: true});

  return (<pre>
    <b>Objects</b>
    {"\n[\n  { C: 2, D: 3 },\n  { D: 1, C: 4 } // different key order\n]\n"}<br/>
    <b>Worksheet when same `header` array is passed to `sheet_add_json`</b>
    <div dangerouslySetInnerHTML={{__html:XLSX.utils.sheet_to_html(ws1)}}/>
    <i>New contents of `header`</i><br/>
    {JSON.stringify(header)}<br/>
    <br/>
    <b>Worksheet when no `header` property is passed to `sheet_add_json`</b>
    <div dangerouslySetInnerHTML={{__html:XLSX.utils.sheet_to_html(ws2)}}/>
  </pre>)
}

:::

HTML Table Input

Create a worksheet or workbook from a HTML DOM TABLE

var ws = XLSX.utils.table_to_sheet(elt, opts);
var wb = XLSX.utils.table_to_book(elt, opts);

XLSX.utils.table_to_sheet takes a table DOM element and returns a worksheet resembling the input table. Numbers are parsed. All other data will be stored as strings.

XLSX.utils.table_to_book produces a minimal workbook based on the worksheet.

Both functions accept options arguments:

Option Name	Default	Description
raw		If true, every cell will hold raw strings
dateNF	FMT 14	Use specified date format in string output
cellDates	false	Store dates as type d (default is n)
sheetRows	0	If >0, read the first sheetRows rows of the table
display	false	If true, hidden rows and cells will not be parsed

To generate the example sheet, assuming the table has ID sheetjs:

var tbl = document.getElementById('sheetjs');
var ws = XLSX.utils.table_to_sheet(tbl);

:::note

table_to_book and table_to_sheet act on HTML DOM elements. Starting from an HTML string, there are two parsing approaches:

A) Table Phantasm: create a DIV with the desired HTML.

/* create element from the source */
var elt = document.createElement("div");
elt.innerHTML = html_source;
document.body.appendChild(elt);

/* generate worksheet */
var ws = XLSX.utils.table_to_sheet(elt.getElementsByTagName("TABLE")[0]);

/* remove element */
document.body.removeChild(elt);

B) Raw HTML: use XLSX.read to read the text in the same manner as CSV.

var wb = XLSX.read(html_source, { type: "string" });
var ws = wb.Sheets[wb.SheetNames[0]];

:::

Add data from a HTML DOM TABLE to an existing worksheet

XLSX.utils.sheet_add_dom(ws, elt, opts);

XLSX.utils.sheet_add_dom takes a table DOM element and updates an existing worksheet object. It follows the same process as table_to_sheet and accepts an options argument:

Option Name	Default	Description
raw		If true, every cell will hold raw strings
dateNF	FMT 14	Use specified date format in string output
cellDates	false	Store dates as type d (default is n)
sheetRows	0	If >0, read the first sheetRows rows of the table
display	false	If true, hidden rows and cells will not be parsed

origin is expected to be one of:

origin	Description
(cell object)	Use specified cell (cell object)
(string)	Use specified cell (A1-style cell)
(number >= 0)	Start from the first column at specified row (0-indexed)
-1	Append to bottom of worksheet starting on first column
(default)	Start from cell A1

A common use case for sheet_add_dom involves adding multiple tables to a single worksheet, usually with a few blank rows in between each table:

function MultiTable() {
  const headers = ["Table 1", "Table2", "Table 3"];

  /* Callback invoked when the button is clicked */
  const xport = React.useCallback(async () => {
    /* This function creates gap rows */
    function create_gap_rows(ws, nrows) {
      var ref = XLSX.utils.decode_range(ws["!ref"]);       // get original range
      ref.e.r += nrows;                                    // add to ending row
      ws["!ref"] = XLSX.utils.encode_range(ref);           // reassign row
    }

    /* first table */
    const ws = XLSX.utils.aoa_to_sheet([[headers[0]]]);
    XLSX.utils.sheet_add_dom(ws, document.getElementById('table1'), {origin: -1});
    create_gap_rows(ws, 1); // one row gap after first table

    /* second table */
    XLSX.utils.sheet_add_aoa(ws, [[headers[1]]], {origin: -1});
    XLSX.utils.sheet_add_dom(ws, document.getElementById('table2'), {origin: -1});
    create_gap_rows(ws, 2); // two rows gap after second table

    /* third table */
    XLSX.utils.sheet_add_aoa(ws, [[headers[2]]], {origin: -1});
    XLSX.utils.sheet_add_dom(ws, document.getElementById('table3'), {origin: -1});

    /* create workbook and export */
    const wb = XLSX.utils.book_new();
    XLSX.utils.book_append_sheet(wb, ws, "Export");
    XLSX.writeFile(wb, "SheetJSMultiTablexport.xlsx");
  });

  return (
    <>
      <button onClick={xport}><b>Export XLSX!</b></button><br/><br/>
      <b>{headers[0]}</b><br/>
      <table id="table1">
        <tr><td>A2</td><td>B2</td></tr>
        <tr><td>A3</td><td>B3</td></tr>
      </table>
      <b>{headers[1]}</b><br/>
      <table id="table2">
        <tr><td>A6</td><td>B6</td><td>C6</td></tr>
        <tr><td>A7</td><td>B7</td><td>C7</td></tr>
      </table>
      <br/>
      <b>{headers[2]}</b><br/>
      <table id="table3">
        <tr><td>A11</td><td>B11</td></tr>
        <tr><td>A12</td><td>B12</td></tr>
      </table>
    </>
  );
}

Delimiter-Separated Output

var csv = XLSX.utils.sheet_to_csv(ws, opts);

As an alternative to the writeFile CSV type, XLSX.utils.sheet_to_csv also produces CSV output. The function takes an options argument:

Option Name	Default	Description
FS	","	"Field Separator" delimiter between fields
RS	"\n"	"Record Separator" delimiter between rows
dateNF	FMT 14	Use specified date format in string output
strip	false	Remove trailing field separators in each record **
blankrows	true	Include blank lines in the CSV output
skipHidden	false	Skips hidden rows/columns in the CSV output
forceQuotes	false	Force quotes around fields

• strip will remove trailing commas from each line under default FS/RS
• blankrows must be set to false to skip blank lines.
• Fields containing the record or field separator will automatically be wrapped in double quotes; forceQuotes forces all cells to be wrapped in quotes.
• XLSX.write with csv type will always prepend the UTF-8 byte-order mark for Excel compatibility. sheet_to_csv returns a JS string and omits the mark. Using XLSX.write with type string will also skip the mark.

Starting from the example worksheet:

function SheetJSCSVTest() {
  var ws = XLSX.utils.aoa_to_sheet([
    ["S", "h", "e", "e", "t", "J", "S"],
    [  1,   2,    ,    ,   5,   6,   7],
    [  2,   3,    ,    ,   6,   7,   8],
    [  3,   4,    ,    ,   7,   8,   9],
    [  4,   5,   6,   7,   8,   9,   0]
  ]);
  return ( <pre>
    <b>Worksheet (as HTML)</b>
    <div dangerouslySetInnerHTML={{__html: XLSX.utils.sheet_to_html(ws)}}/>
    <b>XLSX.utils.sheet_to_csv(ws)</b><br/>
    {XLSX.utils.sheet_to_csv(ws)}<br/><br/>
    <b>XLSX.utils.sheet_to_csv(ws, {'{'} FS: "\t" {'}'})</b><br/>
    {XLSX.utils.sheet_to_csv(ws, { FS: "\t" })}<br/><br/>
    <b>XLSX.utils.sheet_to_csv(ws, {'{'} FS: ":", RS: "|" {'}'})</b><br/>
    {XLSX.utils.sheet_to_csv(ws, { FS: ":", RS: "|" })}<br/>
  </pre> );
}

UTF-16 Text Output

var txt = XLSX.utils.sheet_to_txt(ws, opts);

The txt output type uses the tab character as the field separator. If the codepage library is available (included in full distribution but not core), the output will be encoded in CP1200 and the BOM will be prepended.

XLSX.utils.sheet_to_txt takes the same arguments as sheet_to_csv.

HTML Output

var html = XLSX.utils.sheet_to_html(ws, opts);

As an alternative to the writeFile HTML type, XLSX.utils.sheet_to_html also produces HTML output. The function takes an options argument:

Option Name	Default	Description
id		Specify the id attribute for the TABLE element
editable	false	If true, set contenteditable="true" for every TD
header		Override header (default html body)
footer		Override footer (default /body /html)

Starting from the example worksheet:

function SheetJSHTML() {
  var ws = XLSX.utils.aoa_to_sheet([
    ["S", "h", "e", "e", "t", "J", "S"],
    [  1,   2,    ,    ,   5,   6,   7],
    [  2,   3,    ,    ,   6,   7,   8],
    [  3,   4,    ,    ,   7,   8,   9],
    [  4,   5,   6,   7,   8,   9,   0]
  ]);
  return ( <pre>
    <b>XLSX.utils.sheet_to_html(ws)</b>
    <div dangerouslySetInnerHTML={{__html: XLSX.utils.sheet_to_html(ws)}}/>
  </pre> );
}

Array Output

var arr = XLSX.utils.sheet_to_json(ws, opts);

var aoa = XLSX.utils.sheet_to_json(ws, {header: 1, ...other_opts});

XLSX.utils.sheet_to_json generates different types of JS objects. The function takes an options argument:

Option Name	Default	Description
raw	true	Use raw values (true) or formatted strings (false)
range	from WS	Override Range (see table below)
header		Control output format (see table below)
dateNF	FMT 14	Use specified date format in string output
defval		Use specified value in place of null or undefined
blankrows	**	Include blank lines in the output **

• raw only affects cells which have a format code (.z) field or a formatted text (.w) field.
• If header is specified, the first row is considered a data row; if header is not specified, the first row is the header row and not considered data.
• When header is not specified, the conversion will automatically disambiguate header entries by affixing _ and a count starting at 1. For example, if three columns have header foo the output fields are foo, foo_1, foo_2
• null values are returned when raw is true but are skipped when false.
• If defval is not specified, null and undefined values are skipped normally. If specified, all null and undefined points will be filled with defval
• When header is 1, the default is to generate blank rows. blankrows must be set to false to skip blank rows.
• When header is not 1, the default is to skip blank rows. blankrows must be true to generate blank rows

range is expected to be one of:

range	Description
(number)	Use worksheet range but set starting row to the value
(string)	Use specified range (A1-style bounded range string)
(default)	Use worksheet range (ws['!ref'])

header is expected to be one of:

header	Description
1	Generate an array of arrays ("2D Array")
"A"	Row object keys are literal column labels
array of strings	Use specified strings as keys in row objects
(default)	Read and disambiguate first row as keys

• If header is not 1, the row object will contain the non-enumerable property __rowNum__ that represents the row of the sheet corresponding to the entry.
• If header is an array, the keys will not be disambiguated. This can lead to unexpected results if the array values are not unique!

For the example worksheet:

function SheetJSToJSON() {
  /* original data */
  var ws = XLSX.utils.aoa_to_sheet([
    ["S", "h", "e", "e", "t", "J", "S"],
    [  1,   2,    ,    ,   5,   6,   7],
    [  2,   3,    ,    ,   6,   7,   8],
    [  3,   4,    ,    ,   7,   8,   9],
    [  4,   5,   6,   7,   8,   9,   0]
  ]);

  /* display JS objects with some whitespace */
  const aoo = o => o.map(r => "  " + JSON.stringify(r).replace(/,"/g, ', "').replace(/:/g, ": ").replace(/"([A-Za-z_]\w*)":/g, '$1:')).join("\n");
  const aoa = o => o.map(r => "  " + JSON.stringify(r).replace(/,/g, ', ').replace(/null/g, "")).join("\n");

  return ( <pre>
    <b>Worksheet (as HTML)</b>
    <div dangerouslySetInnerHTML={{__html: XLSX.utils.sheet_to_html(ws)}}/>
    <b>XLSX.utils.sheet_to_json(ws, {'{'} header: 1 {'}'}) [array of arrays]</b><br/>
    [<br/>{aoa(XLSX.utils.sheet_to_json(ws, { header: 1 }))}<br/>]<br/><br/>
    <b>XLSX.utils.sheet_to_json(ws) [objects with header disambiguation]</b><br/>
    [<br/>{aoo(XLSX.utils.sheet_to_json(ws))}<br/>]<br/><br/>
    <b>XLSX.utils.sheet_to_json(ws, {'{'} header: "A" {'}'}) [column names as keys]</b><br/>
    [<br/>{aoo(XLSX.utils.sheet_to_json(ws, { header: "A" }))}<br/>]<br/><br/>
    <b>XLSX.utils.sheet_to_json(ws, {'{'} header: ["A","E","I","O","U","6","9"] {'}'})</b><br/>
    [<br/>{aoo(XLSX.utils.sheet_to_json(ws, { header: ["A","E","I","O","U","6","9"] }))}<br/>]<br/>
  </pre> );
}

Formulae Output

var fmla_arr = XLSX.utils.sheet_to_formulae(ws);

XLSX.utils.sheet_to_formulae generates an array of commands that represent how a person would enter data into an application.

Cells without formulae are written as A1-cell-address=value:

A1=1                   // A1 is the numeric value 1
B1=TRUE                // B1 is the logical value TRUE

String literals are prefixed with a ' in accordance with Excel:

A5='A4+A3              // A5 is the string "A4+A3"

Cells with formulae are written as A1-cell-address=formula:

A5=A4+A3               // A5 is a cell with formula =A4+A3

Array formulae are written as A1-range=formula. They do not include the displayed curly braces:

A4:B4=A2:B2*A3:B3      // A4:B4 array formula {=A2:B2*A3:B3}

Single-cell array formulae are written with single-cell ranges:

C4:C4=SUM(A2:A3*B2:B3) // C4 array formula {=SUM(A2:A3*B2:B3)}

function SheetJSToJSON() {
  var ws = XLSX.utils.aoa_to_sheet([
    ["A", "B", "C"],
    [1, 2, { t: "n", f: "SUM(A2:B2)" }],
    [3, 4, { t: "n", f: "A3+B3" }]
  ]);
  XLSX.utils.sheet_set_array_formula(ws, "A4:B4", "A2:B2*A3:B3");
  XLSX.utils.sheet_set_array_formula(ws, "C4", "SUM(A2:A3*B2:B3)");

  var __html = `\
<i>Values</i>
[
  ["A", "B", "C"],
  [1,  2],
  [3,  4]
]
<i>Formulae</i>
C2     =SUM(A2:B2)
C3     =A3+B3
<i>Array Formulae</i>
A4:B4  {=A2:B2*A3:B3}
C4     {=SUM(A2:A3*B2:B3)}

`;

  return ( <pre>
    <b>Original worksheet</b>
    <div dangerouslySetInnerHTML={{__html}}/>
    <b>XLSX.utils.sheet_to_formulae(ws).join("\n")</b><br/>
    <br/>{XLSX.utils.sheet_to_formulae(ws).join("\n")}
  </pre> );
}