嘗試將更改整體保存為包含自定義對象的數組中的數組

Question

我正在嘗試做出if聲明，如果陣列板與2之前的更改相同，它將通過說“不合法的非法比賽”來警告我。 但是每個數組在3圈后都會變得一樣（因為if(boardHistory.length >= 3){ ），但是它總是警告我，而我卻沒有理由警告我，因為它總是在變化並且永遠不會變成相同的值。

我怎么了

var turn;
var boardSize;
var board;
var boardHistory;
var changer;

function setup() {
    createCanvas(400, 400);
    boardSize = 8;
    turn = false;
    board = [];
    boardHistory = [];
    changer = 0;
    for (var y = 0; y < boardSize; y++) {
        for (var x = 0; x < boardSize; x++) {
            board.push(new Piece(x, y, 0));
        }
    }
    boardHistory.push(board);
}

function mouseClicked() {
    for (var y = 0; y < boardSize; y++) {
        for (var x = 0; x < boardSize; x++) {
            board[y * boardSize + x].colour = changer;
        }
    }
    var play = true;
    if (boardHistory.length >= 3) {
        if (board == boardHistory[(boardHistory.length - 3)]) {
            play = false;
        }
    }
    if (play) {
        turn = !turn;
        boardHistory.push(board);
        console.log("played");
    } else {
        console.log("undid illegal play, " + (boardHistory.length - 3));
        console.log(boardHistory[(boardHistory.length - 3)]);
    }
    console.log(board);

    changer++;
}

function Piece(x, y, colour) {
    this.x = x;
    this.y = y;
    this.colour = colour;
    this.arrayNum = this.y * boardSize + this.x;
}

 var turn; var boardSize; var board; var boardHistory; var changer; function setup() { createCanvas(400, 400); boardSize = 8; turn = false; board = []; boardHistory = []; changer = 0; for(var y = 0; y < boardSize; y++){ for(var x = 0; x < boardSize; x++){ board.push(new Piece(x,y,0)); } } boardHistory.push(board); } function mouseClicked(){ for(var y = 0; y < boardSize; y++){ for(var x = 0; x < boardSize; x++){ board[y*boardSize+x].colour = changer; } } var play = true; if(boardHistory.length >= 3){ if(board == boardHistory[(boardHistory.length-3)]){ play = false; } } if(play){ turn = !turn; boardHistory.push(board); console.log("played"); } else { console.log("undid illegal play, "); } changer++; } function Piece(x, y, colour) { this.x = x; this.y = y; this.colour = colour; this.arrayNum = this.y*boardSize+this.x; }

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Answer 1

我認為您面臨的問題在兩個不同的地方：

boardHistory.push(board);

和

if (board == boardHistory[(boardHistory.length - 3)])

即使您在函數中用鼠標單擊了board的值進行修改，該變量也包含對象的引用，而不是對象的副本。 因此，如果您在一個地方進行更改，則會在另一地方看到它。

我想舉一個例子會更清楚：

var board = [1,2,3]
var boardHist = []

boardHist[0] = board; //This is similar of what you are doing

console.log(board == boardHist[0]); //Obviously we are getting true

board[0] = 5; //Now we change the first value of board

console.log(board == boardHist[0]); //This is still true

console.log(boardHist[0]); //We will get [5,2,3]

嘗試將更改整體保存為包含自定義對象的數組中的數組

問題描述

1 個解決方案

解決方案1
1 已采納 2018-09-26 15:27:19

嘗試將更改整體保存為包含自定義對象的數組中的數組

問題描述

1 個解決方案

解決方案1 1 已采納 2018-09-26 15:27:19

解決方案1
1 已采納 2018-09-26 15:27:19