Question

＆＃13;

<!--- for loop that i have tried --->
<script >
var something = $('textarea[id^="alllthedesc"]');
  $(something).each(function () {
    var innervalue = $(this).val();
    if (innervalue.length > 0) {
        return innervalue
    };
  });
  console.log(innervalue); <
</script>

＆＃13;

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css"> //textarea
<!--- textarea --->

<div class="container">
    <textarea name="alllthedesc1" id="alllthedesc1">
        this is some text for the first one </textarea>
    <textarea name="alllthedesc2" id="alllthedes2">
        this is some text for number 2 </textarea>
    <textarea name="alllthedesc3" id="alllthedesc3">
        this is some text for the number 3 </textarea>
</div>

＆＃13;

我有以下文本区域结构，必须将其放入一个数组中，然后用于警报，即警报将通过循环并显示满足某个条件的每条文本消息。我尝试了一个for循环，但for循环没有返回我想要的值。以下是我的尝试

<!--- bootstrap --->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css"> //textarea
<!--- textarea --->

<div class="container">
    <textarea name="alllthedesc1" id="alllthedesc1">
        this is some text for the first one </textarea>
    <textarea name="alllthedesc2" id="alllthedes2">
        this is some text for number 2 </textarea>
    <textarea name="alllthedesc3" id="alllthedesc3">
        this is some text for the number 3 </textarea>
</div>


<!--- for loop that i have tried --->
<script >
var something = $('textarea[id^="alllthedesc"]');
  $(something).each(function () {
    var innervalue = $(this).val();
    if (innervalue.length > 0) {
        return innervalue
    };
  });
  console.log(innervalue); <
</script>    
<!--- Jquery --->
<script src = "https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js" > </script>

Answer 1

只需使用map()方法而不是each()方法，这样就可以从迭代中返回值。

var something =  $('textarea[id^="alllthedesc"]');

//you need to use map() instead of each() method because each() does not return any value

var innervalue = something.map(function() { 
    if ($(this).val().length > 0){return $(this).val()};
}); // in innervalue you will get all the values

Answer 2

您已声明变量＆＃39; var innervalue＆＃39;在循环内部并在循环外使用它。如果要在外部使用它，请在循环外声明变量，如下所示。

 var innervalue;
    $(something).each(function() { 
    innervalue= $(this).val();
    console.log(innervalue);
    if (innervalue.length > 0){return innervalue};

    });
    console.log(innervalue);

从for循环中返回一个数组对象并将其实现为一个新循环

2 个答案: