Documentation
Learn how to integrate Excel generation into your applications
Mitosis - Excel Templater
Presentation
Mitosis - Excel Templater is a templater engine to create Excel files, inspiring from {Mustache} syntax. It enables to generate complex formatted Excel files without code, just by feeding an Excel template and data to it. It is distributed as a REST API or a npm package for node or browser.
You can try it out through the Demo on the landing page!
How it works
Use Excel to create a template with the formatting and formulae you want and insert placeholders where your data must be mapped.
{tagName} is a simple placeholder. It will be replaced by the value mapping to tagName.
{=tagName} is a numeric placeholder. It will enforce the type of the value under tagName to be numeric.
{?tagName} is a conditional placeholder. It will display the line where it stands only if it is truthy. (Note that the placeholder gets removed, it is not replaced by its value.)
{#tagName} and {/tagName} are contextual and iterative placeholders. If the value under tagName is an object, the placeholders within the lines between both bounds will refer to the fields of this object. If it is an array of objects, the section will be repeated for each element.
Example
Excel Template:
Data:
Result:
The values inserted are formatted according to the format of the cell it belongs to. Values can be anything supported by ExcelJS CellValue type: strings, numbers, dates, or specific structures for formulae, links, styles, ...
Features
Separate Style from content
• Supports: nested iterations and conditionals, named tables, merged cells, images, multiple worksheets, conditional styles
• Updates references in formulae
• Runs on browser or node
• Supports ExcelJS CellValue to set style programmatically
Designed for TypeScript
• In-code types and documentation
• Provides utility to generate the type structure corresponding to the Excel template
• Possibility to integrate type generation in the build process: this ensures template and data are aligned!
Get started easily!
• Try it yourself with the Demo on the landing page.
• The Demo is open-source! You can look at the code to see how to integrate ExcelTemplater in a project.
Known Caveats
• Graphs and plots are sadly not supported because of a restriction from ExcelJS. They will just disappear in your generated file.
• There is currently no iteration over columns because it wasn't needed in my different use cases. Please ping me if you want this supported in the future! This could be my next feature!
• If you get errors when opening your generated Excel file, or a recovery message, try creating a new template file from scratch and copy the content of each worksheet from the original template to the new file.
• If you run into any other restriction or bug, please reach out by e-mail!
Contact
You can contact me at the e-mail below. We can schedule a videocall to discuss your specific needs.
I'm actively maintaining Mitosis - Excel Templater, so do not hesitate to send me your questions, requests or suggestions.
I'm an experienced Software Engineer, from France, and have worked at various companies including Amazon, Safran or my own startup. I am committed to delivering the best software for my customers.
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