69 lines
1.7 KiB
Markdown
69 lines
1.7 KiB
Markdown
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# Knockout
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The `xlsx.core.min.js` and `xlsx.full.min.js` scripts are designed to be dropped
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into web pages with script tags:
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```html
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<script src="xlsx.full.min.js"></script>
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```
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Strictly speaking, there should be no need for a Knockout demo! You can proceed
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as you would with any other browser-friendly library.
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## Array of Arrays
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A common data table is often stored as an array of arrays:
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```js
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var aoa = [ [1,2], [3,4] ];
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```
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This neatly maps to a table with `data-bind="foreach: ..."`:
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```html
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<table data-bind="foreach: aoa">
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<tr data-bind="foreach: $data">
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<td><span data-bind="text: $data"></span></td>
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</tr>
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</table>
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```
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The `sheet_to_json` utility function can generate array of arrays for model use:
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```js
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/* starting from a `wb` workbook object, pull first worksheet */
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var ws = wb.Sheets[wb.SheetNames[0]];
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/* convert the worksheet to an array of arrays */
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var aoa = XLSX.utils.sheet_to_json(ws, {header:1});
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/* update model */
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model.aoa(aoa);
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```
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## Demo
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The easiest observable representation is an `observableArray`:
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```js
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var ViewModel = function() { this.aoa = ko.observableArray([[1,2],[3,4]]); };
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var model = new ViewModel();
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ko.applyBindings(model);
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```
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Unfortunately the nested `"foreach: $data"` binding is read-only. A two-way
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binding is possible using the `$parent` and `$index` binding context properties:
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```html
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<table data-bind="foreach: aoa">
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<tr data-bind="foreach: $data">
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<td><input data-bind="value: $parent[$index()]" /></td>
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</tr>
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</table>
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```
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The demo shows reading worksheets into a view model and writing models to XLSX.
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[](https://github.com/SheetJS/js-xlsx)
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