Filling and Submitting Forms in BAS

Form filling is the backbone of most BAS projects — registration, login, checkout, profile edits. The mechanics are simple, but doing it in a way that looks human and reliably succeeds takes a few deliberate habits.

The basic fill-and-submit flow

A form flow in BAS is a short sequence: find each field by selector, set its value, then trigger submission. Build it field by field, running after each step so you catch a bad selector immediately instead of debugging the whole form at once.

Type like a human, don’t paste

The fastest way to look like a bot is to fill every field instantly. Real users type. Use the typing action with a per-character delay so input arrives at a human pace, and add small random pauses between fields. On sensitive sites this difference alone decides whether a registration sticks.

Dropdowns, checkboxes and radios

These aren’t text fields, so they need their own handling:

• Dropdowns (<select>) — set the option by value or visible text rather than simulating clicks, which is more robust.
• Checkboxes and radios — check the current state first, then toggle only if needed. Blindly clicking can uncheck something already set.
• Custom JS widgets — fake dropdowns built from <div>s aren’t real form controls; you must click to open and click the option, with waits in between.

File uploads

File inputs can’t be “typed” into. BAS provides a dedicated way to attach a local file path to a file input. Point it at a file that exists on the running machine (or one your bot downloaded earlier), then continue the flow.

Submitting reliably

Prefer clicking the actual submit button over firing a form-submit event — many sites attach their logic to the button’s click handler, so a raw submit does nothing. Before clicking:

• Make sure every field finished filling (add a short wait).
• If the site validates inline, give it a moment to clear errors.

Verify the result, don’t assume

The most common silent failure is a bot that “submits” and moves on while the form actually rejected the input. After submitting, check for a success signal — a redirect, a confirmation message, or the absence of an error element. Treat a missing success signal as a failure and branch accordingly.

Forms often sit behind a captcha. That’s the next obstacle, and it has its own article in this guide.