为什么我的比较数组不起作用？

Question

我正在构建一个游戏，我希望从提示中获取玩家的输入，并将其与他们已经使用的输入进行比较，如果他们两次选择相同的内容，则拒绝选择。 这是我的相关代码：

var playerChoiceRow = 0;
var playerChoiceColumn = 0;
var playerAttackArray = [];

function playerAttack(playerChoiceRow,playerChoiceColumn) {
for (var i=0; i<playerAttackArray.length; i++){
    if ([playerChoiceRow,playerChoiceColumn] === playerAttackArray[i]){
        alert("You have already attacked this space, please choose another.");
        playerChoiceRow = prompt("Please choose a number between 0 and 5.");
        playerChoiceColumn = prompt("Please choose a number between 0 and 5.");
    }
}
if (playerChoiceRow === undefined){
    alert("Please choose a number between 0 and 5!");
    playerChoiceRow = prompt("Please choose a number between 0 and 5.");
}
if (playerChoiceColumn === undefined){
    alert("Please choose a number between 0 and 5!");
    playerChoiceColumn = prompt("Please choose a number between 0 and 5.");
}
playerAttackArray.push([playerChoiceRow,playerChoiceColumn]);

while (playerCounter || computerCounter <=4){
    var playerChoiceRow = prompt("Please select row of attack. (0 though 5)")-'';
    var playerChoiceColumn = prompt("Please select column of attack. (0 though 5)")-'';
    playerAttack(playerChoiceRow,playerChoiceColumn);
    if (playerCounter == 5){
        alert("You have sunk all enemy boats!");
        break;
    }
}

Answer 1

在Javascript数组中，比较是关于身份而不是内容； 换句话说，当两个表达式为数组时，两个表达式之间的===仅当它们引用的是同一数组对象时才返回true，而不是两个包含相同事物的数组时才返回true。

您可以通过首先将两面都转换为字符串来解决此问题：

if (""+[playerChoiceRow,playerChoiceColumn] === ""+playerAttackArray[i]) ...