每行的字符数和每个textarea限制的行数 [英] Characters per line and lines per textarea limit

问题描述

我正在尝试在php页面中创建一个多行textarea，我想验证如果用户不能每行插入超过50个字符，或超过50行。
想法是用户可以粘贴电子表格中的内容，但如果一行超过50个字符，其余行将被丢弃，而不会插入下一行。这就是为什么我要避免使用50个单独的文本框的想法。

I'm trying to create a multiline textarea in a php page, and I want to validate so that if the user can't insert more than 50 characters per line, or more than 50 lines. The idea is that the user can paste something from a spreadsheet, but if one line has more than 50 characters, the rest will be discarded, and not inserted in the next line. That's why I want to avoid the idea of having 50 individual textboxes.

如果可以在javascript（或php本身，但我没有）这样做是理想的在php中看到了类似的东西。

It would be ideal if this could be done in javascript (or php itself, but I didn't saw anything like it in php).

谢谢！

更新：感谢所有答案，但是只有在用户提交表单后才能工作，对吧？
例如，如果最大行数为3而不是50，并且用户插入100个连续字符，然后换行，则只剩下50个字符，将输入限制为2而不是3.
希望我很清楚...

UPDATE: Thanks for all that answers, but that would work only after the user submitted the form, right? For example, if the max lines is 3 instead of 50, and the user inserts 100 consecutive characters, and then a line break, it would only have 50 characters left, limiting the inputs to 2 instead of 3. Hope I was clear...

推荐答案

这是基于马修提供的代码，但这个更短并限制行数。

Here it is, based on the code provided by Matthew, but this is shorter and also limits the number of lines.

$lines = array_slice(explode("\n", $string), 0, 50); // max 50 lines

foreach ($lines as $key => $value)
{
    $lines[$key] = substr(trim($value), 0, 50); // max 50 chars
}

$string = implode("\n", $lines);

这篇关于每行的字符数和每个textarea限制的行数的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！