historyReverser & array reverse
historyReverser & array reverse\
"use strict";
/**
*
* @author xgqfrms
* @license MIT
* @copyright xgqfrms
*
* @description historyReverser
* @augments Reverse 逆向 / Recursive 递归
* @example
* @link
*
*/
const historyReverser = (datas = [], text = ``, debug = false) => {
let result = {};
let newDatas = [];
let reverseDatas = [];
let length = datas.length;
if (length === 10) {
if(datas.includes(text)) {
// remove old & add new
let index = datas.indexOf(text);
datas.splice(index, 1);
datas.push(text);
} else {
// add new
datas.push(text);
datas.shift(0);
}
} else {
datas.push(text);
}
newDatas = datas;
datas.forEach(
(item, i) => {
let value = datas[length - i - 1];
reverseDatas.push(value);
}
);
result = {
newDatas,
reverseDatas,
};
return result;
};
export default historyReverser;
export {
historyReverser,
};
tesing
let datas = ["1", "2", "3", "4", "5", "6", "7", "8", "9", "10"]
let text = "5";
// let text = "15";
const historyReverser = (datas = [], text = ``, debug = false) => {
let result = {};
let newDatas = [];
let reverseDatas = [];
let length = datas.length;
if (length === 10) {
if(datas.includes(text)) {
// remove old & add new
let index = datas.indexOf(text);
datas.splice(index, 1);
datas.push(text);
} else {
// add new
datas.push(text);
datas.shift(0);
}
} else {
datas.push(text);
}
newDatas = datas;
datas.forEach(
(item, i) => {
let value = datas[length - i - 1];
reverseDatas.push(value);
}
);
result = {
newDatas,
reverseDatas,
};
return result;
};
let ReverseArray = historyReverser(datas, text);
console.log(`ReverseArray =`, ReverseArray);
MDN & Array
https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array
0.push
-
shift
-
unshift
-
slice
-
splice
-
includes
6.infdexOf
7.lastIndexOf
bug
"use strict";
/**
*
* @author xgqfrms
* @license MIT
* @copyright xgqfrms
*
* @description historyReverser
* @augments Reverse 逆向 / Recursive 递归
* @example
* @link
*
*/
const historyReverser = (datas = [], text = ``, debug = false) => {
if (text === null) {
text = `xyz`;
}
let result = {};
let newDatas = [];
let reverseDatas = [];
let length = datas.length;
if (length === 10) {
if(datas.includes(text)) {
// remove old & add new
let index = datas.indexOf(text);
datas.splice(index, 1);
datas.push(text);
} else {
// add new
datas.push(text);
datas.shift(0);
}
if(datas.includes(text)) {
// remove old & add new
let index = datas.indexOf(text);
datas.splice(index, 1);
datas.push(text);
} else {
// add new
datas.push(text);
datas.shift(0);
}
} else {
datas.push(text);
}
newDatas = datas;
// datas.forEach(
// (item, i) => {
// let value = datas[length - i - 1];
// console.log(`null value`, value);
// reverseDatas.push(value);
// }
// );
if (1 <= length) {
datas.forEach(
(item, i) => {
let value = datas[length - i - 1];
console.log(`null value`, value);
reverseDatas.push(value);
}
);
} else {
reverseDatas = datas;
}
result = {
newDatas,
reverseDatas,
};
return result;
};
export default historyReverser;
export {
historyReverser,
};
OK
unshfit
"use strict";
/**
*
* @author xgqfrms
* @license MIT
* @copyright xgqfrms
*
* @description historyReverser
* @augments Reverse 逆向 / Recursive 递归
* @example
* @link
*
*/
const historyReverser = (datas = [], text = ``, debug = false) => {
// console.log(`datas =`, datas);
// console.log(`text =`, text);
let result = {};
let newDatas = [];
let reverseDatas = [];
let length = datas.length;
// if(datas.indexOf(text) !== -1) {
if(datas.includes(text)) {
// remove old & add new
let index = datas.indexOf(text);
datas.splice(index, 1);
console.log(`datas =`, datas);
datas.unshift(text);
// datas.push(text);
} else {
// add new
if (length === 10) {
datas.splice(9, 1);
datas.unshift(text);
// datas.push(text);
// datas.shift(0);
} else {
// add new
datas.unshift(text);
// datas.push(text);
}
}
newDatas = datas;
reverseDatas = datas;
// let new_length = newDatas.length;
// if (1 <= new_length) {
// let temp = datas;
// reverseDatas = temp.reverse();
// // datas.forEach(
// // (item, i) => {
// // let value = datas[new_length - i - 1];
// // // console.log(`value`, value);
// // reverseDatas.push(value);
// // }
// // );
// } else {
// reverseDatas = datas;
// }
result = {
newDatas,
reverseDatas,
};
return result;
};
export default historyReverser;
export {
historyReverser,
};
本文首发于博客园,作者:xgqfrms,原文链接:https://www.cnblogs.com/xgqfrms/p/10881090.html
未经授权禁止转载,违者必究!