如何在PHP中删除一定数量的字符后切断文本？

Question

我有两个字符串,我想限制为例如前25个字符.有没有办法在第25个字符后切断文本并在字符串末尾添加...？

所以'12345678901234567890abcdefg'会变成'12345678901234567890abcde ...'其中'fg'被切断.

Answer 1

我可以修改pallan的代码吗？

$truncated = (strlen($string) > 20) ? substr($string, 0, 20) . '...' : $string;

如果它更短,则不会添加'...'.

Answer 2

为了避免在单词中间切换,您可能想要尝试该wordwrap功能; 我认为,这样的事情可以做到:

$str = "this is a long string that should be cut in the middle of the first 'that'";
$wrapped = wordwrap($str, 25);
var_dump($wrapped);

$lines = explode("\n", $wrapped);
var_dump($lines);

$new_str = $lines[0] . '...';
var_dump($new_str);

$wrapped 将包含:

string 'this is a long string
that should be cut in the
middle of the first
'that'' (length=74)

该$lines阵列会像:

array
  0 => string 'this is a long string' (length=21)
  1 => string 'that should be cut in the' (length=25)
  2 => string 'middle of the first' (length=19)
  3 => string ''that'' (length=6)

最后,你的$new_string:

string 'this is a long string' (length=21)

使用substr,如下所示:

var_dump(substr($str, 0, 25) . '...');

你得到了:

string 'this is a long string tha...' (length=28)

哪个看起来不那么好:-(

还是,玩得开心!

Answer 3

真的很快,

$truncated = substr('12345678901234567890abcdefg', 0, 20) . '...'

Answer 4

这个很短,并考虑到字边界,它不使用循环,这使得它非常有效

function truncate($str, $chars, $end = '...') {
    if (strlen($str) <= $chars) return $str;
    $new = substr($str, 0, $chars + 1);
    return substr($new, 0, strrpos($new, ' ')) . $end;
}

用法:

truncate('My string', 5); //returns: My...

Answer 5

http://php.net/manual/en/function.mb-strimwidth.php (PHP 4 >= 4.0.6, PHP 5, PHP 7)

<?php
echo mb_strimwidth("Hello World", 0, 10, "...");
echo "<br />";
echo mb_strimwidth("Hello", 0, 10, "...");
?>

输出：

Hello W...
Hello