Ruby on rails 如何在数组中显示类属性

我的haml文件中有这个代码

      = f.select :rate_type, options_for_select(@rate_type, @selected_rate_type), required: true, :style => 'width:125px'

但是我想

def new

    @payer_contract = PayerContract.new(
         id: '',
         description: '',
         type_code: {
             id: '',
             code_key: '',
             display: '',
             code_group: ''
    },
         base_contract_rate: '',
         phase_dates: [{
                           id: '',
                           rate_type: '',
                           institutional: '',
                           professional: ''
                       }],
         donor_claim_phase: '',
         stoploss_amount: '',
         stoploss_reimbursement_percentage: '',
         begin_date: '',
         end_date: '',
         timely_filing_days: '',
         payer: '',
         rate_type: ''
    )

选择阶段日期[费率类型]，而不仅仅是费率类型。我试过这么做

      = f.select :@phase_date.rate_type, options_for_select(@rate_type, @selected_rate_type), required: true, :style => 'width:125px'

但它不起作用。你知道这是什么语法吗？

这样做：

= f.select :rate_type, options_for_select(@rate_type, @selected_rate_type), { required: true }, { :style => 'width:125px' }

更多信息，请参阅