在 vuejs 中求和来自 v-model 的可选值的问题

Question

in this function i want to show what left from amount

 remainingAmount: function() {
            return parseFloat(this.sumAmount) - (parseFloat(this.cash) + parseFloat(this.kNet) + parseFloat(this.kNetOnline));
        }

three parameter cash and knet and knet online are came from v-model, if one of them be null retuen result being NAN? how can i defined these v-model as optional in this function?

Answer 1

i can not find any optional function in js so i solved with conditions:

            var a = this.cash ?  parseFloat(this.cash) :0
            var b = this.kNetOnline ?  parseFloat(this.kNetOnline) :0
            var c = this.kNet ?  parseFloat(this.kNet) :0

but i think is not working for large scale data