javascript - 多个文本区域的字数限制

Question

我正在创建一个包含四个文本区域表单的网站。每个表格都有字数限制。

• textarea1:250 字限制
• textarea2:500 字限制
• textarea3:500 字限制
• textarea4:250 字限制

我尝试使用在尝试解决此问题时发现的现有示例，但似乎没有任何效果。

   <script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.6.4/jquery.min.js"></script>
<script>
var maxwords = 250;
//
function check_length(obj, cnt, rem)
{
    var ary = obj.value.split(" "); // doubled spaces will throw this off
    var len = ary.length;
    cnt.innerHTML = len;
    rem.innerHTML = maxwords - len;
    if (len > maxwords) {
        alert("Message in '" + obj.name + "' limited to " + maxwords + " words.");
        ary = ary.slice(0,maxwords-1);
        obj.value = ary.join(" "); // truncate additional words
        cnt.innerHTML = maxwords;
        rem.innerHTML = 0;
        return false;
    }
    return true;
} 

</script>

HTML

   <textarea name="Message 1" onkeypress="
 return check_length(this,
 document.getElementById('count1'),
 document.getElementById('remaining1'));"></textarea>
Word count: <span id="count1">0</span> &nbsp;
Words remaining: <span id="remaining1">250</span>

<textarea name="Message 2" onkeypress="
 return check_length(this,
 document.getElementById('count2'),
 document.getElementById('remaining2'));"></textarea>
Word count: <span id="count2">0</span> &nbsp;
Words remaining: <span id="remaining2">500</span>

有谁知道这个问题的解决方案吗？

提前致谢，汤姆

Answer 1

向您的函数添加一个额外的参数，并将每次函数调用的 maxWords 发送给它:

function check_length(obj, cnt, rem, maxwords)
{
//... rest of the function would stay the same

当你调用它时，包括最大字数

<textarea name="Message 2" onkeypress="
 return check_length(this,
 document.getElementById('count2'),
 document.getElementById('remaining2'), 250);"></textarea>
Word count: <span id="count2">0</span> &nbsp;
Words remaining: <span id="remaining2">500</span>

删除剩余的单词，

function check_length(obj, cnt, maxwords)
{
    var ary = obj.value.split(" "); // doubled spaces will throw this off
    var len = ary.length;
    cnt.innerHTML = len;

    if (len > maxwords) {
        alert("Message in '" + obj.name + "' limited to " + maxwords + " words.");
        ary = ary.slice(0,maxwords-1);
        obj.value = ary.join(" "); // truncate additional words
        cnt.innerHTML = maxwords;
        return false;
    }
    return true;
} 

在您的 HTML 中，

<textarea name="Message 1" onkeypress="
return check_length(this,
document.getElementById('count1'),250);"></textarea>
Word count: <span id="count1">0</span> &nbsp;