{
  appid: 'wxe43b****4db9e0d',
  cash_fee: '16900',
  mch_id: '153****671',
  nonce_str: 'ntFcYohOQlVjuNrj',
  out_refund_no_0: 'REFUND90210422022****495',
  out_refund_no_1: 'REFUND90210422022****495',
  out_refund_no_2: 'REFUND90210422022****495',
  out_refund_no_3: 'REFUND90210422021****495',
  out_refund_no_4: 'REFUND90210422021****495',
  out_refund_no_5: 'REFUND90210422022****495',
  out_refund_no_6: 'REFUND90210422022****495',
  out_trade_no: '90210****260236495',
  refund_account_0: 'REFUND_SOURCE_RECHARGE_FUNDS',
  refund_account_1: 'REFUND_SOURCE_RECHARGE_FUNDS',
  refund_account_2: 'REFUND_SOURCE_RECHARGE_FUNDS',
  refund_account_3: 'REFUND_SOURCE_RECHARGE_FUNDS',
  refund_account_4: 'REFUND_SOURCE_RECHARGE_FUNDS',
  refund_account_5: 'REFUND_SOURCE_RECHARGE_FUNDS',
  refund_account_6: 'REFUND_SOURCE_RECHARGE_FUNDS',
  refund_channel_0: 'ORIGINAL',
  refund_channel_1: 'ORIGINAL',
  refund_channel_2: 'ORIGINAL',
  refund_channel_3: 'ORIGINAL',
  refund_channel_4: 'ORIGINAL',
  refund_channel_5: 'ORIGINAL',
  refund_channel_6: 'ORIGINAL',
  refund_count: '7',
  refund_fee: '15400',
  refund_fee_0: '1950',
  refund_fee_1: '2950',
  refund_fee_2: '750',
  refund_fee_3: '1500',
  refund_fee_4: '3200',
  refund_fee_5: '3600',
  refund_fee_6: '1450',
  refund_id_0: '5030100792202105010843****244',
  refund_id_1: '5030100792202105020843****046',
  refund_id_2: '5030100792202105080862****822',
  refund_id_3: '5030100792202105080862****403',
  refund_id_4: '5030100792202105080862****727',
  refund_id_5: '5030100792202105080862****984',
  refund_id_6: '5030100792202105080862****520',
  refund_recv_accout_0: '招商银行信用卡7385',
  refund_recv_accout_1: '招商银行信用卡7385',
  refund_recv_accout_2: '招商银行信用卡7385',
  refund_recv_accout_3: '招商银行信用卡7385',
  refund_recv_accout_4: '招商银行信用卡7385',
  refund_recv_accout_5: '招商银行信用卡7385',
  refund_recv_accout_6: '招商银行信用卡7385',
  refund_status_0: 'SUCCESS',
  refund_status_1: 'SUCCESS',
  refund_status_2: 'SUCCESS',
  refund_status_3: 'SUCCESS',
  refund_status_4: 'SUCCESS',
  refund_status_5: 'SUCCESS',
  refund_status_6: 'SUCCESS',
  refund_success_time_0: '2021-05-01 19:56:06',
  refund_success_time_1: '2021-05-02 07:32:23',
  refund_success_time_2: '2021-05-08 11:06:56',
  refund_success_time_3: '2021-05-08 11:07:02',
  refund_success_time_4: '2021-05-08 11:06:49',
  refund_success_time_5: '2021-05-08 11:07:08',
  refund_success_time_6: '2021-05-08 11:00:17',
  result_code: 'SUCCESS',
  return_code: 'SUCCESS',
  return_msg: 'OK',
  sign: '81FEEA1494E023C5B462DA345D14F889',
  total_fee: '16900',
  transaction_id: '4200000****02104196998326642'
}

给你拉一个例子，这笔退款单发生了7次部分退款请求，总实收款额 cash_fee=16900，总退款额 refund_fee=15400，refund_count = 7，下标 $n 就是0,1,2,3,5,6，每次退单的商户退单号就是 out_refund_no_$n。