在某个索引（或索引）处插入值 javascript

Question

我在完成一项任务时遇到了障碍。如何将值插入给定的索引或索引？

例如，我正在开发一个刽子手游戏。如果单词是“harry”，并且玩家猜到了字母“r”，我如何将我的下划线数组转换为“_ _ r r _”？

我下面的内容从一个单独的 js 文件中获取一个单词，创建一个下划线数组（返回单词的每个字母一个），然后，当用户猜测一个字母时，它会找到一个或多个下划线的索引该字母的出现次数。

**我已经更新了下面的代码。最后的 for 循环是我的下划线数组（wordToGuess[]）和用户输入的拼接。这可以满足我的需要，但它也将最后猜到的字母放在前面。例如，如果单词是“bold”并且用户猜到的最后一个字母是“l”，那么 wordToGuess 数组将是 lbold。这里有人知道这是为什么吗？我敢肯定，我忽略了一些简单的事情，但它让我发疯了。

Javascript

var word;

$(document).ready(function () {
    SetGameBoard();
});

//When guess button is clicked
$('#BtnGuess').click(function () {
    CheckGuess();
});

function GetPhrase() {
    word = ReturnWord();
    alert(word);
}

function SetGameBoard() {
    GetPhrase();
    wordToGuess = new Array(word.length);

     // Place underscore for each letter in the answer word in the DivWord div
    for (var i = 0; i < word.length; i++){
       wordToGuess[i] = "_ ";
     }
    $('#DivWord').html(wordToGuess);
}


function CheckGuess() {
    var pos = 0;
    var posArray = [];
    var guessLetter = $('#tbGuessLetter').val();

    while ((pos = word.indexOf(guessLetter, pos)) > -1) {
        posArray.push(++pos);
    }

    if (posArray.length == 0) {
        alert(guessLetter + " is not in the word.");
    }

    //Splice in correct letters. Not working 100%
    for(i=0; i < wordToGuess.length; i++){
        wordToGuess.splice(posArray[i], 1, guessLetter);
        }
        $('#DivWord').html(wordToGuess);

    alert(posArray);

    alert(guessLetter);
}

Answer 1

试试这样的：

var word=["_","_","
_"];
word[1]="r";

现在你的数组变成了 ,1,

Answer 2

要就地修改数组，您需要Array.prototype.splice()

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/splice

来自文档：

var myFish = ['angel', 'clown', 'mandarin', 'surgeon'];

// removes 0 elements from index 2, and inserts 'drum'
var removed = myFish.splice(2, 0, 'drum');
// myFish is ['angel', 'clown', 'drum', 'mandarin', 'surgeon']
// removed is [], no elements removed

// removes 1 element from index 3
removed = myFish.splice(3, 1);
// myFish is ['angel', 'clown', 'drum', 'surgeon']
// removed is ['mandarin']

// removes 1 element from index 2, and inserts 'trumpet'
removed = myFish.splice(2, 1, 'trumpet');
// myFish is ['angel', 'clown', 'trumpet', 'surgeon']
// removed is ['drum']

// removes 2 elements from index 0, and inserts 'parrot', 'anemone' and 'blue'
removed = myFish.splice(0, 2, 'parrot', 'anemone', 'blue');
// myFish is ['parrot', 'anemone', 'blue', 'trumpet', 'surgeon']
// removed is ['angel', 'clown']

// removes 2 elements from index 3
removed = myFish.splice(3, Number.MAX_VALUE);
// myFish is ['parrot', 'anemone', 'blue']
// removed is ['trumpet', 'surgeon']

看起来您想要的行为在第三个示例中，他们将“鼓”替换为“小号”。

Answer 3

编辑、更新

试试

var word = "word" // `word` : input `String`
    , _word = word.split("")
    , mask = word.replace(/./g, "_")
    , _mask = mask.split("")
    , temp = ""
    , guess = function (letter) {
         _mask[
             $.inArray(
                 letter
                 , _word
                 , temp.match(letter) !== null 
                   ? temp.lastIndexOf(letter) + 1 
                   : 0
             )
         ] = letter;
         temp = _mask.join("");
         return temp.indexOf("_") !== -1 ? temp : word
     };

 $("input").on("input", function (e) {
     $("#results").text(guess(e.target.value));
     e.target.value = "";
 });

var word = "word" // `word` : `String`
    , _word = word.split("")
    , mask = word.replace(/./g, "_")
    , _mask = mask.split("")
    , temp = ""
    , guess = function (letter) {
         _mask[
             $.inArray(
                 letter
                 , _word
                 , temp.match(letter) !== null 
                   ? temp.lastIndexOf(letter) + 1 
                   : 0
             )
         ] = letter;
         temp = _mask.join("");
         return temp.indexOf("_") !== -1 ? temp : word + " !"
     };

 $("input").on("input", function (e) {
     $("#results").text(guess(e.target.value));
     e.target.value = "";
 })

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<input type="text" />
<div id="results"></div>

Answer 4

做一些类似的事情

string replaceAt = function(str, index, character) {
    return str.substr(0, index) + character + str.substr(index+character.length);
}

hangmanString = replaceAt(hangmanString, 3, 'r');

无耻地盗取here.