试图用相应的索引中的另一个字符串的字符替换字符串的索引

Question

document.onkeyup = function(event){ 
    if(answer.indexOf(event.key) > -1){ 
    console.log(answer.indexOf(event.key)); 
    console.log(typeof event.key); 
    //cover[answer.indexOf(event.key)] = event.key; this doesnt work 
    //cover.replace(cover[answer.indexOf(event.key)],event.key); this doesnt 
    work 
    console.log(cover); 
    } 
} 

我有一个字符串，看起来像这样：“-------”代表相同的隐藏答案长度。当用户点击答案字符串中的一个键时，我希望该字符在相同索引处出现在隐藏字符串中。

Answer 1

var answer = 'correcthorsebatterystaple'; 
 
// generate an array of '-' the same length as the answer 
 
var cover = answer.split('').map(x => '-'); 
 
document.getElementById('c').innerText = cover.join(''); 
 

 
document.onkeyup = function(e) { 
 
    var key = e.key; 
 
    for (var i = 0; i < cover.length; i++) { 
 
    // for each instance of the pressed letter in the answer, replace the corresponding dash(es) in cover 
 
    if (answer[i] === key) cover[i] = key; 
 
    } 
 
    document.getElementById('c').innerText = cover.join(''); 
 
}

<span id="c" style="font-family:monospace"></span>