js-wrench/dist/modules/deepCopy.js

JS函数库

import isArray from './isArray';
import isDate from './isDate';
import isRegExp from './isRegExp';
/**
 * @description 对象深拷贝
 * 来源Vuex https://github.com/vuejs/vuex/blob/dev/src/util.js 解决了循环引用问题
 * 对其深度拷贝进行二次优化, 添加Date其他类型的判断 {time:new Date(), regexp:/\w+/}
 * @param {*} obj 要进行拷贝的源数据
 * @param {Array<any>} [cache=[]] 利用数组存储已经拷贝过的数据, 每次拷贝会从cache中查询有没有拷贝过
 * @return {*}  {*} 返回拷贝的数据
 * @example deepCopy({age:12, time:new Date(), regexp:/\w+/, fn:function(){}}, [])
 */
const deepCopy = (obj, cache = []) => {
    if (obj === null || typeof obj !== 'object')
        return obj;
    let hit = cache.filter(function (c) {
        return c.original === obj;
    })[0];
    if (hit)
        return hit.copy;
    let copy;
    //添加Date和RegExp类型
    if (isDate(obj))
        copy = new Date(obj);
    else if (isRegExp(obj))
        copy = new RegExp(obj);
    else if (isArray(obj))
        copy = [];
    else
        copy = {};
    cache.push({
        original: obj,
        copy,
    });
    Object.keys(obj).forEach((key) => {
        copy[key] = deepCopy(obj[key], cache);
    });
    return copy;
};
export default deepCopy;