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	| title | pagination_prev | pagination_next | sidebar_custom_props | ||
|---|---|---|---|---|---|
| Clipboard Data | demos/data/index | demos/cloud/index | 
 | 
Spreadsheet software like Excel typically support copying and pasting cells and data. This is implemented through the Clipboard ("Pasteboard" in MacOS).
When copying a selection of cells, Excel for Windows stores a screenshot of the selected cells as an image. It also creates and stores a number of strings and files for the various formats, including TSV, CSV, HTML, RTF, SYLK, DIF, XLSB, XLS (both '97-2004 and '95), and SpreadsheetML 2003.
Not all Clipboard APIs offer access to all clipboard types.
:::note Tested Deployments
Each browser demo was tested in the following environments:
| Browser | Date | Notes | 
|---|---|---|
| Chrome 126 | 2024-06-30 | |
| Safari 17.3 | 2024-06-30 | text/rtfnot supported | 
:::
Browser Reading (paste)
Clipboard data can be read from a paste event.
The event clipboardData property has a getData method which returns a string
compatible with the "string" type in the SheetJS read method1.
The following example reads from the HTML clipboard and generates a XLSX file
using the SheetJS writeFile method2:
document.onpaste = function(e) {
  /* get HTML */
  var str = e.clipboardData.getData('text/html');
  /* parse */
  var wb = XLSX.read(str, {type: "string"});
  /* DO SOMETHING WITH wb HERE */
};
getData accepts one argument: the desired MIME type. Tested browsers support:
| MIME type | Data format | 
|---|---|
| text/plain | TSV (tab separated values) | 
| text/html | HTML | 
| text/rtf | RTF (rich text format) | 
Live Demo
Open a file in Excel, copy some cells, then come back to this window. Click on "RESULT" below and paste (Control+V for Windows, Command+V for Mac).
function ClipboardRead() {
  const [csvs, setCSVs] = React.useState([ "", "", "" ]);
  /* Set up paste handler */
  const paste = React.useCallback((e) => {
    /* this demo will read 3 different clipboard data types */
    var mime_arr = [ 'text/plain', 'text/html', 'text/rtf' ];
    /* get clipboard data for each type */
    var data_arr = mime_arr.map(mime => e.clipboardData.getData(mime));
    /* parse each data string into a workbook */
    var wb_arr = data_arr.map(str => XLSX.read(str, {type: "string"}));
    /* get first worksheet from each workbook */
    var ws_arr = wb_arr.map(wb => wb.Sheets[wb.SheetNames[0]]);
    /* generate CSV for each "first worksheet" */
    var result = ws_arr.map(ws => XLSX.utils.sheet_to_csv(ws));
    setCSVs(result);
  }, []);
  return ( <>
      {csvs[0] && (<pre><b>Data from clipboard TSV  (text/plain)</b><br/>{csvs[0]}</pre>)}
      {csvs[1] && (<pre><b>Data from clipboard HTML (text/html)</b><br/>{csvs[1]}</pre>)}
      {csvs[2] && (<pre><b>Data from clipboard RTF  (text/rtf)</b><br/>{csvs[2]}</pre>)}
      {csvs.every(x => !x) && <b onPaste={paste}>Copy data in Excel, click here, and paste (Control+V)</b>}
  </> );
}
Reading Files
Modern browsers support reading files that users have copied into the clipboard.
:::caution pass
Due to browser API limitations, the system file browser should be used to select and copy spreadsheets into the clipboard.
:::
The event clipboardData.files property, if it is set, is a list of files.
function ClipboardReadFiles() {
  const [data, setData] = React.useState([]);
  /* Set up paste handler */
  const paste = React.useCallback(async(e)=>{
    const result = [];
    /* loop over files */
    const files = e.clipboardData.files || [];
    for(let i = 0; i < files.length; ++i) {
      const file = files.item(i);
      /* filter MIME type for spreadsheets */
      if(!file.type.match(/excel|sheet|csv/)) continue;
      /* read data */
      const wb = XLSX.read(await file.arrayBuffer());
      /* capture sheet names */
      result.push([file.name, wb.SheetNames]);
    }
    setData(result);
  }, []);
  return ( <>
    {data.map((f,idx) => (<pre key={idx}>
      <b>Sheet Names from {f[0]}</b><br/>{f[1].join("\n")}
    </pre>))}
    {!data.length && (<b onPaste={paste}>Copy files, click here, and paste (Control+V)</b>)}
  </> );
}
Browser Writing (copy)
Clipboard data can be written from a copy event.
The event clipboardData property has a setData method which accepts a string
that can be generated using type: "string" in the SheetJS write method3.
The following example generates an HTML string from the first sheet of a SheetJS workbook object and loads the string into the HTML clipboard:
document.oncopy = function(e) {
  /* get HTML of first worksheet in workbook */
  var str = XLSX.write(wb, {type: "string", bookType: "html"});
  /* set HTML clipboard data */
  e.clipboardData.setData('text/html', str);
  /* prevent the browser from copying the normal data */
  e.preventDefault();
};
setData accepts two arguments: MIME type and new data.
The following table lists the supported MIME types and the bookType4 value
that must be passed to the SheetJS write method:
| MIME type | Data format | bookType | 
|---|---|---|
| text/plain | TSV (tab separated values) | txt | 
| text/html | HTML | html | 
Browsers do not currently support assigning to the text/rtf clipboard type.
Live Demo
This demo creates a simple workbook from the following HTML table:
| SheetJS | Clipboard | Demo | 
| bookType | RTF | |
| source | HTML Table | 
Create a new file in Excel then come back to this window. Select the text below and copy (Control+C for Windows, Command+C for Mac). Go back to the Excel file, select cell A1, and paste.
function ClipboardWrite() {
  /* Set up copy handler */
  const copy = React.useCallback((e) => {
    /* generate workbook from table */
    var wb = XLSX.utils.table_to_book(document.getElementById("srcdata"));
    /* get HTML of first worksheet in workbook */
    var str = XLSX.write(wb, {type: "string", bookType: "html"});
    /* set HTML clipboard data */
    e.clipboardData.setData('text/html', str);
    /* prevent the browser from copying the normal data */
    e.preventDefault();
  }, []);
  return (
    <b onCopy={copy}>Select this text, copy (Control+C), and paste in Excel</b>
  );
}
Electron
Electron Clipboard API supports HTML and RTF clipboards.
There are special methods for specific clipboard types:
| File Type | Read Clipboard Data | Write Clipboard Data | 
|---|---|---|
| TSV | clipboard.readText | clipboard.writeText | 
| HTML | clipboard.readHTML | clipboard.writeHTML | 
| RTF | clipboard.readRTF | clipboard.writeRTF | 
Each method operates on JS strings.
clipboard.write can assign to multiple clipboard types:
const { clipboard } = require('electron');
const XLSX = require('xlsx');
function copy_first_sheet_to_clipboard(workbook) {
  clipboard.write({
    text: XLSX.write(wb, {type: "string", bookType: "txt"}),
    rtf:  XLSX.write(wb, {type: "string", bookType: "rtf"}),
    html: XLSX.write(wb, {type: "string", bookType: "html"})
  });
}
- 
See "Supported Output Formats" in "Writing Files" for details on bookType↩︎