docs.sheetjs.com/docz/docs/07-csf/07-features/07-vba.md

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---
sidebar_position: 7
---
import current from '/version.js';
import Tabs from '@theme/Tabs';
import TabItem from '@theme/TabItem';
import CodeBlock from '@theme/CodeBlock';
# VBA and Macros
<details>
<summary><b>File Format Support</b> (click to show)</summary>
Note that XLSX does not support macros. The XLSM file format is nearly
identical to XLSX and supports macros.
| Formats | Basic | Storage Representation |
|:--------|:-----:|:-----------------------------------|
| XLSM | ✔ | `vbaProject.bin` file in container |
| XLSX | * | Not supported in format (use XLSM) |
| XLSB | ✔ | `vbaProject.bin` file in container |
| XLS | ✔ | Intercalated in CFB container |
Asterisks (*) mark features that are not supported by the file formats. There is
no way to embed VBA in the XLSX format.
</details>
VBA Macros are stored in a special data blob that is exposed in the `vbaraw`
property of the workbook object when the `bookVBA` option is `true`. They are
supported in `XLSM`, `XLSB`, and `BIFF8 XLS` formats. The supported format
writers automatically insert the data blobs if it is present in the workbook and
associate with the worksheet names.
:::note
The `vbaraw` property stores raw bytes. [SheetJS Pro](https://sheetjs.com/pro)
offers a special component for extracting macro text from the VBA blob, editing
the VBA project, and exporting new VBA blobs.
:::
## Demos
The export demos focus on [an example](pathname:///vba/SheetJSVBAFormula.xlsm)
that includes the following user-defined functions:
```vb
Function GetFormulaA1(Cell As Range) As String
GetFormulaA1 = Cell.Formula
End Function
Function GetFormulaRC(Cell As Range) As String
GetFormulaRC = Cell.Formula2R1C1
End Function
```
### Copying Macros
After downloading the sample file, the demo extracts the VBA blob and creates
a new workbook including the VBA blob. Click the button to create the file and
open in a spreadsheet editor that supports VBA:
<Tabs groupId="platform">
<TabItem value="browser" label="Web Browser">
```jsx live
function SheetJSVBAFormula() { return ( <button onClick={async () => {
/* Extract VBA Blob from test file */
const url = "/vba/SheetJSVBAFormula.xlsm";
const raw_data = await (await fetch(url)).arrayBuffer();
const blob = XLSX.read(raw_data, {bookVBA: true}).vbaraw;
/* generate worksheet and workbook */
const worksheet = XLSX.utils.aoa_to_sheet([
["Cell", "A1", "RC"],
[
{t:"n", f:"LEN(A1)"}, // A2
{t:"s", f:"GetFormulaA1(A2)"}, // B2
{t:"s", f:"GetFormulaRC(A2)"} // C2
]
]);
const workbook = XLSX.utils.book_new();
XLSX.utils.book_append_sheet(workbook, worksheet, "Sheet1");
/* add VBA blob to new workbook */
workbook.vbaraw = blob;
/* create an XLSM file and try to save to SheetJSVBANeu.xlsm */
XLSX.writeFile(workbook, "SheetJSVBANeu.xlsm", { bookVBA: true });
}}><b>Click to Generate file!</b></button> ); }
```
</TabItem>
<TabItem value="nodejs" label="NodeJS">
0) Install the dependencies:
<CodeBlock language="bash">{`\
npm init -y
npm i --save https://cdn.sheetjs.com/xlsx-${current}/xlsx-${current}.tgz`}
</CodeBlock>
1) Save the following script to `generate_file.js`:
```js title="generate_file.js"
const XLSX = require("xlsx");
(async() => {
/* Extract VBA Blob from test file */
const url = "https://docs.sheetjs.com/vba/SheetJSVBAFormula.xlsm";
const raw_data = await (await fetch(url)).arrayBuffer();
const blob = XLSX.read(raw_data, {bookVBA: true}).vbaraw;
/* generate worksheet and workbook */
const worksheet = XLSX.utils.aoa_to_sheet([
["Cell", "A1", "RC"],
[
{t:"n", f:"LEN(A1)"}, // A2
{t:"s", f:"GetFormulaA1(A2)"}, // B2
{t:"s", f:"GetFormulaRC(A2)"} // C2
]
]);
const workbook = XLSX.utils.book_new();
XLSX.utils.book_append_sheet(workbook, worksheet, "Sheet1");
/* add VBA blob to new workbook */
workbook.vbaraw = blob;
/* create an XLSM file and try to save to SheetJSVBANeu.xlsm */
XLSX.writeFile(workbook, "SheetJSVBANeu.xlsm", { bookVBA: true });
})();
```
2) Run the script:
```bash
node generate_file.js
```
This script will generate `SheetJSVBANeu.xlsm`.
</TabItem>
</Tabs>
### Extracting VBA Blobs
To obtain the blob, `bookVBA: 1` must be set in the `read` or `readFile` call.
The following example extracts the embedded VBA blob in a workbook:
<Tabs groupId="platform">
<TabItem value="browser" label="Web Browser">
```jsx live
function SheetJSExtractVBA(props) {
const [msg, setMsg] = React.useState("Select a macro-enabled file");
return ( <>
<b>{msg}</b><br/>
<input type="file" onChange={async(e) => {
/* parse workbook with bookVBA: true */
const wb = XLSX.read(await e.target.files[0].arrayBuffer(), {bookVBA: true});
/* get vba blob */
if(!wb.vbaraw) return setMsg("No VBA found!");
const blob = wb.vbaraw;
/* download to vbaProject.bin */
setMsg("Attempting to download vbaProject.bin");
const url = URL.createObjectURL(new Blob([blob]));
const a = document.createElement("a");
a.download = "vbaProject.bin"; a.href = url;
document.body.appendChild(a); a.click();
document.body.removeChild(a);
}}/>
</> );
}
```
</TabItem>
<TabItem value="nodejs" label="NodeJS">
0) Install the dependencies:
<CodeBlock language="bash">{`\
npm init -y
npm i --save https://cdn.sheetjs.com/xlsx-${current}/xlsx-${current}.tgz`}
</CodeBlock>
1) Save the following script to `extract_vba.js`:
```js title="extract_vba.js"
const fs = require("fs"), XLSX = require("xlsx");
const wb = XLSX.readFile(process.argv[2], { bookVBA: true });
if(!wb.vbaraw) throw new Error("Could not find VBA blob!");
fs.writeFileSync("vbaProject.bin", wb.vbaraw);
```
2) Run the script:
```bash
node extract_vba.js SheetJSMacroEnabled.xlsm
```
This script will generate `vbaProject.bin`. It can be added to a new workbook.
</TabItem>
</Tabs>
### Exporting Blobs
To ensure the writers export the VBA blob:
- The output format must support VBA (`xlsm` or `xlsb` or `xls` or `biff8`)
- The workbook object must have a valid `vbaraw` field
- The `write` or `writeFile` call must include the option `bookVBA: true`
This example uses [`vbaProject.bin`](pathname:///vba/vbaProject.bin) from the
[sample file](pathname:///vba/vbaProject.bin):
```jsx live
function SheetJSVBAPrepared() { return ( <button onClick={async () => {
/* Download prepared VBA blob */
const url = "/vba/vbaProject.bin";
const blob = new Uint8Array(await (await fetch(url)).arrayBuffer());
/* generate worksheet and workbook */
const worksheet = XLSX.utils.aoa_to_sheet([
["Cell", "A1", "RC"],
[
{t:"n", f:"LEN(A1)"}, // A2
{t:"s", f:"GetFormulaA1(A2)"}, // B2
{t:"s", f:"GetFormulaRC(A2)"} // C2
]
]);
const workbook = XLSX.utils.book_new();
XLSX.utils.book_append_sheet(workbook, worksheet, "Sheet1");
/* add VBA blob to new workbook */
workbook.vbaraw = blob;
/* create an XLSM file and try to save to SheetJSVBAPreparedNeu.xlsm */
XLSX.writeFile(workbook, "SheetJSVBAPreparedNeu.xlsm", { bookVBA: true });
}}><b>Click to Generate file!</b></button> ); }
```
## Details
### Code Names
Excel will use `ThisWorkbook` (or a translation like `DieseArbeitsmappe`) as the
default Code Name for the workbook. Each worksheet will be identified using the
default `Sheet#` naming pattern even if the worksheet names have changed.
A custom workbook code name will be stored in `wb.Workbook.WBProps.CodeName`.
For exports, assigning the property will override the default value.
Worksheet and Chartsheet code names are in the worksheet properties object at
`wb.Workbook.Sheets[i].CodeName`. Macrosheets and Dialogsheets are ignored.
The readers and writers preserve the code names, but they have to be manually
set when adding a VBA blob to a different workbook.
### Macrosheets
Older versions of Excel also supported a non-VBA "macrosheet" sheet type that
stored automation commands. These are exposed in objects with the `!type`
property set to `"macro"`.
Under the hood, Excel treats Macrosheets as normal worksheets with special
interpretation of the function expressions.
#### Detecting Macros in Workbooks
The `vbaraw` field will only be set if macros are present. Macrosheets will be
explicitly flagged. Combining the two checks yields a simple function:
```js
function wb_has_macro(wb/*:workbook*/)/*:boolean*/ {
if(!!wb.vbaraw) return true;
const sheets = wb.SheetNames.map((n) => wb.Sheets[n]);
return sheets.some((ws) => !!ws && ws['!type']=='macro');
}
```