我正在学习过滤 javascript 中的嵌套 arrays ，我相信这个例子可以帮助我更好地理解它。下面是对象。
const game = () => {
return {
player1: {
username: 'ABC',
playingAs: 'X'
},
player2: {
username: 'XYZ',
playingAs: '0'
},
board:
[
['✓', null, 'X'],
['X', '✓', null],
['✓', null, 'X']
]
}
};我的代码在下面
const {player1: {username: PlayerA, playingAs:PlayerAMark}, player2: {username: PlayerB, playingAs:PlayerBMark}} = game();
const {board: board} = game();
//is there any efficient way to do it without a loop using a filter?
for (const item in board) {
//One approach which comes to my mind is to loop. but that is what I don't think would be a learning curve for me.
}我正在尝试这样的事情
const array = board;
for (const item in board) {
console.log(array.filter(innerArray => innerArray[item] !== 'X'));
}我专注于实施一些可以帮助我返回的有效方法
Player1 marked 'X' at 3,1,3 and
Player 2 marked '0' at location at 0,2,1我只坚持过滤这个板多维数组。
感谢您在这方面的帮助。
回答1
您也可以使用 reduce 功能。我们可以使用以下代码获得所需的输出：
function printForPlayer(player, board) {
var indexes = board.reduce((acc,row)=>[...row.reduce((acc2,item,index) => item==player.playingAs ? [...acc2,index+1] : acc2, []),...acc], [])
console.log(`${player.username} marked ${player.playingAs} at ${indexes.join(',')}`)
}
printForPlayer(game().player1, game().board);
printForPlayer(game().player2, game().board);这有点复杂，但它可以在没有循环的情况下工作
回答2
一种方法是遍历每一行以创建一个数组，其中包含玩家拥有自己符号的所有位置。
使用https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/Reduce，我们可以https://stackoverflow.com/a/20798754/5625547，然后在循环之后，使用https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/join
const data = {player1: {username: 'ABC', playingAs: 'X'}, player2: {username: 'XYZ', playingAs: '0'}, board: [['0', null, 'X'], ['X', '0', null], ['0', null, 'X'] ] };
const logPlayer = (player) => {
const ox = data[player].playingAs;
let indexes = [];
for (let row in data.board) {
const ii = data.board[row].reduce((prev, cur, i) => (cur === ox) ? [ ...prev, i ] : prev,[]);
if (ii.length > 0) ii.map(i => indexes.push(`${+row + 1}-${i + 1}`));
}
console.log(`${player} has placed an '${ox}' on the following places (row-column)`, indexes.join(", "));
}
logPlayer('player1');
logPlayer('player2');player1 has placed an 'X' on the following places (row-column) 1-3, 2-1, 3-3
player2 has placed an '0' on the following places (row-column) 1-1, 2-2, 3-1回答3
所以这是我的解决方案，它对我有用。
首先，null 总是呈现为 0。所以我必须更新我的数组，如下所述
board:
[
['✓', null, 'X'],
['X', '✓', null],
['✓', null, 'X']
]其次，在更新数组中的板 value 后，以下解决方案对我有用。
const {
player1: {username: PlayerA, playingAs:PlayerAMark},
player2: {username: PlayerB, playingAs:PlayerBMark},
board: GameBoard
} = game();
let array = GameBoard.entries();
let tick = [];
let cross = [];
for (const [index,element] of array) {
tick.push(element.indexOf(PlayerBMark)+ 1);
cross.push(element.indexOf(PlayerAMark)+ 1);
}
console.log('Player ', PlayerA, ' Clicked ', PlayerAMark ,' at '+ cross);
console.log('Player ',PlayerB, ' Clicked ', PlayerBMark ,' at '+ tick);这是结果。
Player ABC Clicked X at 3,1,3
Player XYZ Clicked ✓ at 1,2,1感谢大家的帮助。但是，我仍然在寻找我们如何提高其性能并避免循环？
再次感谢。