Question

我在这里的游戏是一个猜谜游戏，它计算猜谜次数，并且不包含任何重复的猜想。

我正在尝试将变量try从函数try传递给函数try，但是它将不起作用。计数保持为0，但是当我通过sameGuess.length时，它为什么起作用？

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

当您访问array.length时，该值将被复制，这意味着即使您将一个值添加到数组中，该值也不会更新：

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，您的代码可以正常工作，尽管您可以像现在一样删除它的tries方面并直接使用sameGuess.length。

有关Pass by Reference or Pass by Value的更多讨论，请参见此帖子。

Answer 2

您应该尝试输入= sameGuess.length;一会儿！

JavaScript函数未传递变量

2 个答案: