def parse(self, response):
    self.data = {}
for form_input in response.css('form#aspnetForm input'):
    name = form_input.xpath('@name').extract()[0]
try:
    value = form_input.xpath('@value').extract()[0]
except IndexError:
    value = ''
self.data[name] = value
self.data['ctl00$MainContent$ScriptManager1'
    ] = """ctl00$MainContent$UpdatePanel1|ctl00$MainContent$agentList"""
self.data['__EVENTTARGET'] = 'ctl00$MainContent$List'
self.data['__EVENTARGUMENT'] = 'Page$1'
Сканирование страниц с данными PostBack javascript Python Scrapy