如何使用Scrapy找出同名类的数量？

Question

如何使用Scrapy找出类名中带有“on”一词的类的数量

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Answer 1

• response.xpath('//*[has-class("on")]')提供选择器（所有具有“on”的类）
• len(response.xpath('//*[has-class("on")]'))给出了长度——在本例中是类的数量