vue 计算属性的复杂入门到入土computed计算

1.使用 for 循环

  
        {{totalPrcie}}
    
    
    

2. 使用for in

   // 2for in 用法
                totalPrcie() {
                    let total = 0;
                    for (let i in this.books) {
                        total += this.books[i].price
                    }
                    return total

                }

3. for  of

                // 3 for of 用法
                totalPrcie() {
                    let total = 0;
                    for (let i of this.books) {
                        total += i.price
                    }
                    return total

                }

4. forEach 

    // 4 forEach 用法
                totalPrcie() {
                    let total = 0;
                    this.books.forEach(item => {
                        total += item.price
                    });
                    return total
                }

5.map

   // 5 map
                totalPrcie() {
                    let total = 0;
                    this.books.map(item => {
                        total += item.price
                    })
                    return total
                }

6.filter

                //6 filter
                totalPrcie() {
                    let total = 0;
                    this.books.filter(item => {
                        total += item.price
                    })
                    return total
                }

7.reduce

     totalPrcie() {
                    return this.books.reduce(function(total, item) {
                        return total + item.price
                    }, 0)
                }

                // 箭头函数写法
                totalPrcie() {
                    return this.books.reduce((total, item) =>
                        total + item.price, 0)
                }
            },