import '../css/detail.css';// 找到字符串中重复次数最多的字符
function findMax(str) {let maxChar = '';let maxValue = 1;if (!str.length) return;let arr = str.replace(/\s/g, '').split('');let obj = {};for (let i = 0; i < arr.length; i++) {if (!obj[arr[i]]) {obj[arr[i]] = 1;} else {obj[arr[i]]++;}}let keys = Object.keys(obj);for (let j = 0; j < keys.length; j++) {if (obj[keys[j]] > maxValue) {maxValue = obj[keys[j]];maxChar = keys[j];}}return {maxChar, maxValue}
}function findMax1() {let maxChar = '';let maxValue = 1;let h = {};if (!str.length) return;let arr = str.replace(/\s/g, '').split('');for (let i = 0; i < arr.length; i++) {let a = arr[i];h[a] === undefined ? h[a] = 1 : h[a]++;if (h[a] > maxValue) {maxChar = a;maxValue = h[a];}}return {maxChar, maxValue}
}function findMax2() {let maxChar = '';let maxValue = 1;if (!str.length) return;let arr = str.replace(/\s/g, '').split('');let obj = arr.reduce((acc, curVal) => {acc[curVal] ? acc[curVal]++ : acc[curVal] = 1;if (acc[curVal] > maxValue) {maxChar = curVal;maxValue = acc[curVal];}return acc;}, {}) return {maxChar, maxValue}
}
/* \d 任意一个数字，0~9 中的任意一个\w 任意一个字母或数字或下划线，也就是 A~Z,a~z,0~9,_ 中任意一个\s 包括空格、制表符、换页符等空白字符的其中任意一个
. 小数点可以匹配除了换行符（\n）以外的任意一个字符
*/
function findMax3(str) {let maxChar = '';let maxValue = 1;if (!str.length) return;let arr = str.replace(/\s/g, '').split('');let obj = {};str.replace(/\s/g, '').replace(/(\w)/g, (word, p) => {obj[p] ? obj[p]++ : obj[p] = 1;if (obj[p] > maxValue) {maxValue = obj[p];maxChar = p;}});return {maxChar, maxValue}}function findMax4(str) {let maxChar = '';let maxValue = 1;if (!str.length) return;let arr = str.replace(/\s/g, '').split('');Array.prototype.getMost = function() {let obj = this.reduce((acc, cur) => {acc[cur] ? acc[cur]++ : acc[cur] = 1;acc.max = acc[cur] > acc.max ? acc[cur] : acc.max;acc.key = acc[cur] > acc.max ? cur : acc.key;return acc;}, {});return obj;}// return arr.getMost();
}const str = 'this is a test 222222 ts project. skajdf; 222sldjfwel p'
const reducer = (accumulator, currentValue, b, c) => {let obj = {};obj[b] = currentValue;return obj;
}
const array1 = [1, 2, 3, 4];
// console.log(array1.reduce(reducer));console.log(findMax(str));
console.log('findMax1', findMax4(str));
/*** 输入一个整形数组，数组里有正数也有负数。数组中连续的一个或多个整数组成一个子数组，每个子数组都有一个和。 求所有子数组的和的最大值，要求时间复杂度为O(n)。*/
function findMaxSubArr(arr) {console.log(arr)let max = arr[0];let currSum = 0;for (let i = 0; i < arr.length; i++) {if (currSum < 0) {currSum = arr[i];} else {currSum += arr[i]; }if (currSum > max) {max = currSum;}}return max;
}// console.log('maxsubarr', findMaxSubArr([1, -2, 3, 10, -4, 7, 2, -5]));
// 输出结果
console.log('begin');
setTimeout(() => {console.log('settimeout 1')Promise.resolve().then( () => {console.log('promise 1')setTimeout(() => {console.log('settimeout 2');});}).then(() => {console.log('promise 2');})
}, 0);
console.log('end');
/*** 类数组转成数组*/
const nodes = document.querySelectorAll('div');
// nodes.map(item => {});// 1.for直接遍历// 2.这种方法是借用了数组原型中的slice方法，返回一个数组
Array.prototype.slice.call(nodes).map(item => {});
[].slice.call(nodes).map(item => {console.log()});// 3.Array.from() 方法从一个类似数组或可迭代对象中创建一个新的数组实例。
Array.from(nodes).map(item => {})// 4.同样是ES6中新增的内容，扩展运算符（…）也可以将某些数据结构转为数组
const nodeList = [...nodes];
function getlist(a,b,c,d) {// console.log(arguments);// console.log([...arguments][0])
}
getlist(11, 2, 3, 4);
// 使用reduce方法实现forEach、map、filter
const arr1 = [12, 21, 3];
const arr2 = arr1.map(function(item) {// console.log(this, item)return item*2
}, { msg: 'mapping' })
// console.log(arr1, arr2)
// github上的
Array.prototype.selfMap = function () {const ary = thisconst result = []const [ fn, thisArg ] = [].slice.call(arguments)if (typeof fn !== 'function') {throw new TypeError(fn + 'is not a function') }for (let i = 0; i < ary.length; i++) {result.push(fn.call(thisArg, ary[i], i, ary))}return result
}Array.prototype.reduceMap = function (fn, thisArg) {// return (list) => {// 不怎么愿意写下面这两个判断条件const list = thisif (typeof fn !== 'function') {throw new TypeError(fn + 'is not a function') }if (!Array.isArray(list)) {throw new TypeError('list must be a Array')}if (list.length === 0) return []return list.reduce((acc, value, index) => {return acc.concat([ fn.call(thisArg, value, index, list) ])}, [])// }
}
// mine
Array.prototype.imitateMap = function () {const list = this;const result = []const [fn, thisArg] = [].slice.call(arguments)if (typeof fn !== 'function') {throw new TypeError(fn + 'is not a function');}for (let i = 0; i < list.length; i++) {result.push(fn.call(thisArg, list[i], i, list));}return result;
}Array.prototype.imitateReduceMap = function () {const list = this;const result = []const [fn, thisArg] = [].slice.call(arguments)if (typeof fn !== 'function') {throw new TypeError(fn + 'is not a function');}if (!Array.isArray(list)) {throw new TypeError(list + 'is not a Array');}return list.reduce((acc, curValue, index) => {return acc.concat([fn.call(thisArg, curValue, index, list)]);}, [])
}
const imitateReduceMap1 = function (fn, thisArg) {return (list) => {const result = []if (typeof fn !== 'function') {throw new TypeError(fn + 'is not a function');}if (!Array.isArray(list)) {throw new TypeError(list + 'is not a Array');}return list.reduce((acc, curValue, index) => {return acc.concat([fn.call(thisArg, curValue, index, list)]);}, [])}
}console.log('imitateMap', arr1, arr1.imitateMap(function(item) {console.log('imitateMap this', this)return item + 1
}, { msg: 'mapping' }) )
console.log('imitateReduceMap', [ 1, 2, 3 ].imitateReduceMap(x => x + 1));
console.log('imitateReduceMap1', imitateReduceMap1(x => x + 1)([ 1, 2, 3 ]));
/*** 实现repeat方法*/
function repeat(func, times, wait) {return (str) => {let count = 0;const timer = setInterval(() => {if (count < times) {// func.call(this, str);count++;} else {clearInterval(timer);}}, wait);}
}const repeatFunc = repeat(alert, 3, 2000)repeatFunc('helloworld');
/*** 实现一个简单的双向绑定* 1.发布-订阅模式* 2.脏值检测* 3.数据劫持* Vue.js 采用的是 数据劫持+发布/订阅模式 的方式，通过 Object.defineProperty() 来劫持各个属性的 setter/getter， 在数据变动时发布消息给订阅者（Wacther）, 触发相应的监听回调*/
// 基于Object.defineProperty 实现数据劫持，利用了对Vue.js实现双向绑定的思想
const obj = {}
Object.defineProperty(obj, 'txt',{get:function(){return obj},set:function(newValue){document.getElementById('txt').value = newValuedocument.getElementById('show-txt').innerHTML = newValue}
})
document.addEventListener('keyup', function(e){obj.txt = e.target.value
})
