JS操作

数组

1.筛选两个数组间相同的数据

数组列表

let initList = [1, 2, 35, 15, 48, 68, 48, 52];
let list = [35, 68];
console.log(initList.filter((item) => list.some((val) => val == item)));

数组对象

let initList = [{id:2,name:"hello"},{id:12,name:"world"},{id:32,name:"ni"},{id:35,name:"hao"},{id:23,name:"世界"}];
let list = [2, 23];
console.log(initList.filter((item) => list.some((val) => val == item.id)));

2.筛选数组对象的属性是否含有某个值

let list = [{id:2,name:"hello"},{id:12,name:"world"},{id:32,name:"ni"},{id:35,name:"hao"},{id:23,name:"世界"}];
console.log(list.some(item=>{return item.id==32}));

3.保留数组对象中的个别属性并生成新数组

let list = [{id:2,name:"hello",age:12},{id:12,name:"world",age:12},{id:32,name:"ni",age:16},{id:35,name:"hao",age:24},{id:23,name:"世界",age:32}];
console.log("原数组",list);
//注意对象要用{}包含
console.log("新数组",list.map(({id,name})=>{return {id,name}}));

4.通过JSON转换数组对象为字符串

数组对象转字符串

let list = [{id:2,name:"hello",age:12},{id:12,name:"world",age:12},{id:32,name:"ni",age:16},{id:35,name:"hao",age:24},{id:23,name:"世界",age:32}];
console.log(JSON.stringify(list));

字符串转数组对象

//注意避免双引号和单引号问题
let str = '[{"id":2,"name":"hello","age":12},{"id":12,"name":"world","age":12},{"id":32,"name":"ni","age":16},{"id":35,"name":"hao","age":24},{"id":23,"name":"世界","age":32}]';
console.log(JSON.parse(str));

5.取出对象数组的某个属性并拼接成字符串

//注意避免双引号和单引号问题
let list = [{id:2,name:"hello",age:12},{id:12,name:"world",age:12},{id:32,name:"ni",age:16},{id:35,name:"hao",age:24},{id:23,name:"世界",age:32}];
let names=list.map(item=>{return item.name}).join(';');
console.log(names);

6.获取指定属性的数组下标

//注意避免双引号和单引号问题
let list = [{id:2,name:"hello",age:12},{id:12,name:"world",age:12},{id:32,name:"ni",age:16},{id:35,name:"hao",age:24},{id:23,name:"世界",age:32}];
let index=list.findIndex(item=>item.id==35);
console.log(index);

7.根据子数据id获取树结构数组对象的所有id并组成数组

1. 主要调用方法,摘自JS树形结构数据

/**
 * 显示层级数据
 * @param tree {Array} 树数据
 * @param func {Function} 回调函数
 * @param field {String} 字段名称
 * @param path {Array} 路径数据
 * @returns {*[]|[]|*}
 */
export function treeFindPath(tree, func, field = "", path = []) {
  if (!tree) return [];
  for (const data of tree) {
    field === "" ? path.push(data) : path.push(data[field]);
    if (func(data)) return path;
    if (data.children) {
      const findChildren = treeFindPath(
        data.children,
        func,
        field,
        path
      );
      if (findChildren.length) return findChildren;
    }
    path.pop();
  }
  return [];
}

2. 方法使用

let tree = [
  {
    id: 1,
    text: "一级",
    children: [
      {
        id: 2,
        text: "二级",
        children: [
          {
            id: 3,
            text: "三级一",
          },
          {
            id: 4,
            text: "三级二",
          },
          {
            id: 5,
            text: "三级三",
          },
        ],
      },
    ],
  },
];
console.log(treeFindPath(tree, (data) => data.id === 4, "id"));
console.log(treeFindPath(tree, (data) => data.id === 4, "text"));

字符串

1.字符替换

let str="'dfds'fe'32'eee'";
//替换第一个匹配字符
console.log(str.replace("'","-"))
//替换所有匹配字符
console.log(str.replaceAll("'","-"))