我的嵌套循环不起作用

Question

我正在尝试将输入的文本与预定义数组中的单词列表相匹配。但是，它没有 returning 任何东西，甚至 console.log 也没有 return 任何东西。我无法弄清楚为什么 out 循环没有启动。任何帮助将不胜感激。

var actions = ["north", "south", "east", "west", "up", "down", "get", "take", "pick up", "use", "drop", "open", "close"];
var inputTextBox = document.getElementById("inputTextBox");

inputTextBox.addEventListener("keypress", function(event) {
    var stringArray = [];
    var x = event.which || event.keyCode; 
    var inString = inputTextBox.value.toLowerCase();

    if (x === 13) {
        stringArray = inString.split(" ");
        console.log("stringArray is --- " + stringArray + " --- length is " + stringArray.length);
        for (var i = 0; i < stringArray; i++) {
            console.log("outer loop is " + stringArray[i]);
            for (var j = 0; j < actions.length; j++) {
                if (stringArray[i] === actions[j]) {
                    console.log(stringArray[i]);
                }
            }
        }
    }
}

<input id="inputTextBox" type="text" maxlength="200" placeholder="words here" autofocus></input>

Answer 1

您忘记使用 length 属性，因为 stringArray 是一个数组，您必须使用它的 length.

来迭代它

for (var i = 0; i < stringArray.length; i++) {
 ................................^^^^

"However, it's not returning anything, even the console.log doesn't return anything."

要查看更改，您必须按 enter。

var x = event.which || event.keyCode;

event.which 属性表示按下的特定键或按钮，13 是 enter 命令的键。

var actions = ["north", "south", "east", "west", "up", "down", "get", "take", "pick up", "use", "drop", "open", "close"];
var inputTextBox = document.getElementById("inputTextBox");

inputTextBox.addEventListener("keypress", function(event) {
 var stringArray = [];
 var x = event.which || event.keyCode; 
 var inString = inputTextBox.value.toLowerCase();
 

 if (x === 13) {
 stringArray = inString.split(" ");
 console.log("stringArray is --- " + stringArray + " --- length is " + stringArray.length);
  for (var i = 0; i < stringArray.length; i++) {
   console.log("outer loop is " + stringArray[i]);
   for (var j = 0; j < actions.length; j++) {
    if (stringArray[i] === actions[j]) {
     console.log(stringArray[i]);
    }
   }
  }
 }

});

<input id="inputTextBox" type="text" maxlength="200" placeholder="words here" autofocus></input>

Answer 2

在您的第一个 forloop 中，而不是 i < stringArray 试试这个我 < stringArray.length

for (var i = 0; i < stringArray.length; i++) {
        console.log("outer loop is " + stringArray[i]);
        for (var j = 0; j < actions.length; j++) {
            if (stringArray[i] === actions[j]) {
                console.log(stringArray[i]);
            }
        }
    }

我的嵌套循环不起作用

My nested loops not working

javascript

arrays

for-loop

nested-loops