如何在同一网页上有多个字符计数，而每个字符计数不会相互影响

How to have multiple character counts on the same web page without each character count affecting each other?

本文关键字：字符 影响 网页      更新时间：2023-09-26

如何让字符数影响同一网页上的不同文本区域字段，而不影响其他字符数。我有一个id为#description和另一个id是#another-description 的文本区域字段

HTML

<li><textarea name="description" id="description"></textarea>
<div><span class="character-count"></span></div></li>
<li><textarea name="another_description" id="another-description"></textarea>
<div><span class="character-count"></span></div></li>

Jquery

$(document).ready(function() {  
    var max = 4000;
    $('.character-count').text('4000 characters left');
    $('#description')
    .keydown(function(event){
        if (event.keyCode != 8 && event.keyCode != 46 && $(this).val().length >= max) {
            event.preventDefault();
        }
    })
    .keyup(function(){
        var $this = $(this),
            val = $this.val().slice(0, max),
            val_length = val.length,
            left = max - val_length;
        $('.character-count').text(left + ' characters left');
        $this.val(val);
    });
});

您可以创建一个函数，将每个变量保持在闭包中：

function countCharacters( input, output, max ) {
    var $input = $(input);
    var $output = $(output);
    $output.text(max + ' characters left');
    $input
        .keydown(function(event) {
            if (event.keyCode != 8 &&
                event.keyCode != 46 &&
                $input.val().length >= max)
                event.preventDefault();
        })
        .keyup(function() {
            var val = $input.val().slice(0, max);
            var left = max - val.length;
            $input.val(val);
            $output.text(left + ' characters left');
        });
}
countCharacters('#description', '.character-count', 4000);
countCharacters('#another_description', '.character-count-2', 3000);

编辑：要专门处理相同的类，请使用同级选择器：

countCharacters('#description', '#description + div .character-count', 4000);
countCharacters('#another_description', '#another_description + div .character-count', 3000);

只需像一样向跨度添加id

<li><textarea name="description" id="description"></textarea>
<div><span class="character-count" id="count1"></span></div></li>
<li><textarea name="another_description" id="another-description"></textarea>
<div><span class="character-count" id="count2"></span></div></li>

如果只想影响描述的计数标签，请使用id count1

 $('#count1').text(left + ' characters left');

请尝试下面的代码，您的代码非常好。我已经创建了一个函数，使用它可以应用于任意多个文本字段。请参考jsfiddle-https://jsfiddle.net/sashant9/8feprLfa/

HTML-->

<span id="character-count-1" ></span>
<textarea id="description_1"></textarea>
</br></br>
<span id="character-count-2" ></span>
<textarea id="description_2"></textarea>

jQuery-->

    var max = 4000;
    var textbox_selector_1 = '#description_1';
    var textbox_selector_2 = '#description_2';
    var count_indicator_1 = '#character-count-1';
    var count_indicator_2 = '#character-count-2';
    textbox_character_count(count_indicator_1, textbox_selector_1);
    textbox_character_count(count_indicator_2, textbox_selector_2);

function textbox_character_count(count_indicator_1, textbox_selector_1){
    $(count_indicator_1).text('4000 characters left');
       $(textbox_selector_1)
    .keydown(function(event){
        if (event.keyCode != 8 && event.keyCode != 46 && $(this).val().length >= max) {
            event.preventDefault();
        }
    })
    .keyup(function(){
        var $this = $(this),
            val = $this.val().slice(0, max),
            val_length = val.length,
            left = max - val_length;
        $(count_indicator_1).text(left + ' characters left');
        $this.val(val);
    });
}
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