python基础知识之将item写入JSON文件：

pipelines.py

import json

class xxPipeline(object):
     def __init__(self):
         self.filename=open("xx.json","wb")
     def process_item(self, item, spider):
         jsontext=json.dumps(dict(item),ensure_ascii=False) + ",\n"
         self.filename.write(jsontext.encode("utf-8"))
         return item
     def close_spider(self,spider):
           self.filename.close()

注意：须将它的类添加到 settings.py文件ITEM_PIPELINES 配置

ITEM_PIPELINES = {"mySpider.pipelines.xxPipeline":300｝

也可通过命令scrapy crawl xx(爬虫名字) -o xx.json

scrapy crawl xx(爬虫名字) -o xx.csv

scrapy crawl xx(爬虫名字) -o xx.xml