js判断任意数值接近数组中的某个值

可以是数组，也可以是数组对象，看需求定义

    let val = ''
     for (let i = 0; i < this.allData.length; i++) {
         if (this.days >= this.allData[i].num) {
             val = i
             break
         }
     }
    

如果数据不规则，则先将数组进行排序

let allData= [
    {name:'a',num:14},
    {name:'b',num:5},
    {name:'c',num:29},
    {name:'d',num:33},
    {name:'e',num:9},
]

console.log(allData);

let allData1 = allData.sort(function(a,b) {
    return a.num - b.num
})
console.log(allData1);