python - How to set an nonexistent field in Python ClientForm?

Question

I'm using mechanize (which uses clientform) for some web crawling in python and since it doesn't support JS, I want to set a value of an unexistent input in a form (the input is generated by JS). How can I do this?

The error is similar to the one you get if you try to execute

from mechanize import Browser
br = Browser()
page = br.open('http://google.com')
br.select_form(nr = 0)
br['unexistent'] = 'hello'

Answer 1

您需要先将控件添加到窗体，然后再添加fixup窗体。

br.form.new_control('text','unexistent',{'value':''})
br.form.fixup()
br['unexistent'] = 'hello'

这确实没有很好的记录，并且在下面的源代码中fixup()有评论：

This method should only be called once, after all controls have been
added to the form.

但是，它看起来并没有做任何太危险的事情。可能至少先添加控件，然后再弄乱表单中的任何其他内容。