How do you select choices in a form using Python?

Answer 1

Here are some basic usage examples to get you going:

>>> import mechanize
>>> br = mechanize.Browser()
>>> br.open('http://www.w3schools.com/html/html_forms.asp')

Forms have a name attribute; sometimes it's empty though:

>>> [f.name for f in br.forms()]
['searchform', None, None, None, None, 'input0']

Forms have a sequence of controls; controls also have names:

>>> forms = [f for f in br.forms()]
>>> forms[1].controls[0].name
'firstname'
>>> [c.name for c in forms[3].controls]
['sex']

You can get a listing of items in a control:

>>> forms[3].controls[0].get_items()
[<Item name='male' id=None type='radio' name='sex' value='male'>, <Item name='female' id=None type='radio' name='sex' value='female'>]

For radio buttons, you have to make a single selection:

>>> forms[3]['sex'] = ['male']

But the selection has to be in a list:

>>> forms[3]['sex'] = 'male'
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Library/Python/2.6/site-packages/mechanize/_form.py", line 2782, in __setitem__
    control.value = value
  File "/Library/Python/2.6/site-packages/mechanize/_form.py", line 1977, in __setattr__
    self._set_value(value)
  File "/Library/Python/2.6/site-packages/mechanize/_form.py", line 1985, in _set_value
    raise TypeError("ListControl, must set a sequence")
TypeError: ListControl, must set a sequence

For check boxes you can make multiple selections:

>>> [(c.name, c.get_items()) for c in forms[4].controls]
[('vehicle', [<Item name='Bike' id=None type='checkbox' name='vehicle' value='Bike'>, <Item name='Car' id=None type='checkbox' name='vehicle' value='Car'>])]
>>> forms[4]['vehicle'] = ['Bike', 'Car']

You can find more info here (link stolen from Matt Hempel :).