"{"list":[{"date":"2023-02-01","click_count":0,"exposure_count":0,"income":0,"req_succ_count":1,"slot_id":4071202390577885,"ecpm":-nan,"exposure_rate":0.000000000,"click_rate":0.000000000,"slot_str":"4071202390577885","ad_slot":"SLOT_ID_WEAPP_TEMPLATE"},{"date":"2023-02-01","click_count":0,"exposure_count":1,"income":0,"req_succ_count":30,"slot_id":8040321819858439,"ecpm":0.000000000,"exposure_rate":0.033333333,"click_rate":0.000000000,"slot_str":"8040321819858439","ad_slot":"SLOT_ID_WEAPP_BANNER"}],
"summary":{"click_count":0,"exposure_count":1,"income":0,"req_succ_count":31,"ecpm":0.000000000,"exposure_rate":0.032258065,"click_rate":0.000000000},"total_num":2}"

你这个返回的数据有问题："ecpm":-nan 是什么鬼，你让我php怎么解析？直接报错NULL