5.3 KiB
Processing JSON and JS Data
JSON and JS data tend to represent single worksheets. This section will use a few utility functions to generate workbooks:
Create a new Worksheet
var workbook = XLSX.utils.book_new();
The book_new
utility function creates an empty workbook with no worksheets.
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.
API
Create a worksheet from an array of arrays of JS values
var worksheet = XLSX.utils.aoa_to_sheet(aoa, opts);
The aoa_to_sheet
utility function walks an "array of arrays" in row-major
order, generating a worksheet object. The following snippet generates a sheet
with cell A1
set to the string A1
, cell B1
set to B2
, etc:
var worksheet = XLSX.utils.aoa_to_sheet([
["A1", "B1", "C1"],
["A2", "B2", "C2"],
["A3", "B3", "C3"]
])
"Array of Arrays Input" describes the function and the
optional opts
argument in more detail.
Create a worksheet from an array of JS objects
var worksheet = XLSX.utils.json_to_sheet(jsa, opts);
The json_to_sheet
utility function walks an array of JS objects in order,
generating a worksheet object. By default, it will generate a header row and
one row per object in the array. The optional opts
argument has settings to
control the column order and header output.
"Array of Objects Input" describes the function and
the optional opts
argument in more detail.
Examples
"Zen of SheetJS" contains a detailed example "Get Data from a JSON Endpoint and Generate a Workbook"
The database
demo includes examples of working with
databases and query results.
Processing HTML Tables
API
Create a worksheet by scraping an HTML TABLE in the page
var worksheet = XLSX.utils.table_to_sheet(dom_element, opts);
The table_to_sheet
utility function takes a DOM TABLE element and iterates
through the rows to generate a worksheet. The opts
argument is optional.
"HTML Table Input" describes the function in more detail.
Create a workbook by scraping an HTML TABLE in the page
var workbook = XLSX.utils.table_to_book(dom_element, opts);
The table_to_book
utility function follows the same logic as table_to_sheet
.
After generating a worksheet, it creates a blank workbook and appends the
spreadsheet.
The options argument supports the same options as table_to_sheet
, with the
addition of a sheet
property to control the worksheet name. If the property
is missing or no options are specified, the default name Sheet1
is used.
Examples
Here are a few common scenarios (click on each subtitle to see the code):
HTML TABLE element in a webpage (click to show)
<!-- include the standalone script and shim. this uses the UNPKG CDN -->
<script src="https://unpkg.com/xlsx/dist/shim.min.js"></script>
<script src="https://unpkg.com/xlsx/dist/xlsx.full.min.js"></script>
<!-- example table with id attribute -->
<table id="tableau">
<tr><td>Sheet</td><td>JS</td></tr>
<tr><td>12345</td><td>67</td></tr>
</table>
<!-- this block should appear after the table HTML and the standalone script -->
<script type="text/javascript">
var workbook = XLSX.utils.table_to_book(document.getElementById("tableau"));
/* DO SOMETHING WITH workbook HERE */
</script>
Multiple tables on a web page can be converted to individual worksheets:
/* create new workbook */
var workbook = XLSX.utils.book_new();
/* convert table "table1" to worksheet named "Sheet1" */
var sheet1 = XLSX.utils.table_to_sheet(document.getElementById("table1"));
XLSX.utils.book_append_sheet(workbook, sheet1, "Sheet1");
/* convert table "table2" to worksheet named "Sheet2" */
var sheet2 = XLSX.utils.table_to_sheet(document.getElementById("table2"));
XLSX.utils.book_append_sheet(workbook, sheet2, "Sheet2");
/* workbook now has 2 worksheets */
Alternatively, the HTML code can be extracted and parsed:
var htmlstr = document.getElementById("tableau").outerHTML;
var workbook = XLSX.read(htmlstr, {type:"string"});
Chrome/Chromium Extension (click to show)
The chrome
demo shows a complete example and details the
required permissions and other settings.
In an extension, it is recommended to generate the workbook in a content script and pass the object back to the extension:
/* in the worker script */
chrome.runtime.onMessage.addListener(function(msg, sender, cb) {
/* pass a message like { sheetjs: true } from the extension to scrape */
if(!msg || !msg.sheetjs) return;
/* create a new workbook */
var workbook = XLSX.utils.book_new();
/* loop through each table element */
var tables = document.getElementsByTagName("table")
for(var i = 0; i < tables.length; ++i) {
var worksheet = XLSX.utils.table_to_sheet(tables[i]);
XLSX.utils.book_append_sheet(workbook, worksheet, "Table" + i);
}
/* pass back to the extension */
return cb(workbook);
});