JavaScript 函數不傳遞變量

Question

我這里的游戲是猜謎游戲，計算猜的次數，不包括任何重復的猜測。

我試圖將變量嘗試從函數嘗試傳遞到函數嘗試，但它不起作用。 計數仍然為 0，但是當我通過 sameGuess.length 時它起作用了，這是為什么？

let random = Math.round(Math.random()*100);
let guess = false;
let sameGuess = []
let tries = sameGuess.length;


function game(){
    while (guess === false){
        let myGuess = prompt('Guess a number between 0-100:');
        numCheck(myGuess);
        if (myGuess == random){
            guess = true;
            repeats(myGuess, sameGuess);
            attempts(tries, sameGuess);    
        }else if (myGuess < random){
            repeats(myGuess, sameGuess);
            alert('Your number was too small, try again!');
            guess = false;    
        }else if (myGuess > random){
            repeats(myGuess, sameGuess);
            alert('Your answer was too big, try again!');
            guess = false;
        }
    }
}

function attempts(tries, sameGuess){
    if (sameGuess.length == 1){
        alert('Well done, you got it frist try!');
        document.write("<h1>GUESSING GAME</h1><p>Thank you for playing the Guessing Game <br> Created by Jonathan Fox</p>");
    }else if (sameGuess.length <= 15){
        alert('You took ' + sameGuess.length + ' tries');
        alert('Well done, you didn\'t take too many tries!');
        document.write("<h1>GUESSING GAME</h1><p>Thank you for playing the Guessing Game <br> Created by Jonathan Fox</p>");
    }else if (sameGuess.length >=16){
        alert('You took ' + sameGuess.length + ' tries');
        alert('You got it, but lets see less tries next time!'); 
        document.write("<h1>GUESSING GAME</h1><p>Thank you for playing the Guessing Game <br> Created by Jonathan Fox</p>");
    }
}

function repeats(myGuess, sameGuess){
    if ((sameGuess.indexOf(myGuess)) == -1){
        (sameGuess.push(myGuess));
    }else alert('You have already guessed that number! - Dont worry, i haven\'t counted it!');
}

function numCheck(myGuess){
    if (isNaN(myGuess)){
        alert('Enter a number, don\'t try and be sneaky!');
    }
}

game ();

Answer 1

當您訪問array.length ，該值被復制，這意味着即使在您向數組添加值后它也不會更新：

var array = [];
var length = array.length;
console.log(length); // 0

array.push('Some value');
console.log(length); // Still 0, since it was copied, it is _not_ a reference to the live value
console.log(array.length); // 1, this is a live reference to the length of the array

就目前而言，您的代碼運行良好，盡管看起來您可以像現在一樣刪除它的tries方面並直接使用sameGuess.length 。

有關通過引用傳遞或通過值傳遞的更多討論，請參閱此帖子。

Answer 2

你應該把trys = sameGuess.length; 在你的時間里！