forEach用例

forEach 用例

<button onclick="summyFunction()">点我</button>
<script>
var sum = 0;
var numbers = [65, 44, 12, 4];
var maskWidth = [{ value: 0 }, { value: 0 }, { value: 0 }, { value: 0 }, { value: 0 }, { value: 0 }];
var lineWidth = [{ value: 16 }, { value: 16 }, { value: 16 }, { value: 16 }, { value: 16 }, { value: 16 }];
​
function summyFunction() {
    var arr3=[]
    numbers.forEach((item,index)=>{
        sum+=item;                              // 求和
        const arr2 = numbers[index]             // 记录数组中的每个值
        arr3.push(numbers[index])               // 组成新数组 push
        console.log('arr2',arr2)
        console.log('arr3',arr3)
        const maskWidth = this.maskWidth[index]  // 记录数组中每个值
        const lineWidth = this.lineWidth[index]  // 记录数组中每个值
        console.log('maskWidth',maskWidth)
        console.log('lineWidth',lineWidth)
    })
    console.log('arr322222',arr3)
    demo.innerHTML = sum;
}
</script>