Passare dati a un template

Static HTML is fine, but real pages show different data per user. You make pages dynamic by passing data from your view into the template.

Add keyword arguments to render_template. Each name you pass becomes a variable you can use inside the HTML file.

Inside the template, print a value with double curly braces. Flask swaps the expression for its result when the page renders.

Those {{ }} markers mean output this value here. Anything inside is evaluated and its result is written into the page.

You can pass as many keyword arguments as you need. Each one is independent and available throughout the template.

Values are not limited to text. You can hand a template a list or any Python object and work with it in the markup.

Use a dot to reach attributes, just like in Python. Templates read object properties the same intuitive way you do in code.

For a dictionary, use either the dot or bracket form. Jinja2 tries attribute access first, then falls back to a key lookup.

If a variable is undefined, Jinja2 renders nothing instead of crashing. That keeps a small typo from breaking the whole page.

Transform a value on the fly with a filter, written after a pipe. Filters format text without cluttering your Python view.

Do heavy work in Python and pass ready values in. Templates should display data, not compute it, which keeps pages simple.

How do you output a variable named title inside a Jinja2 template?

You now pass data through keyword arguments and print it with double curly braces, even reaching attributes and applying filters. Great progress! 🚀