php - 在第四个换行符后切断字符串

Question

我遇到了问题，我想在第四个换行符之后截断一个长字符串，并让它以“...”继续

<?php
$teststring = "asddsadsadsadsaa\n
               asddsadsadsadsaa\n
               asddsadsadsadsaa\n
               asddsadsadsadsaa\n
               asddsadsadsadsaa\n
               asddsadsadsadsaa\n";
?>

应该变成:

<?php
$teststring = "asddsadsadsadsaa\n
               asddsadsadsadsaa\n
               asddsadsadsadsaa\n
               asddsadsadsadsaa...";
?>

我知道如何在第一个 \n 之后断开字符串，但我不知道如何在第四个之后断开。

我希望你能帮助我。

Answer 1

你可以把绳子拆开，然后把你需要的所有部分都拿出来

$newStr = ""; // initialise the string
$arr = explode("\n", $teststring);
if(count($arr) > 4) { // you've got more than 4 line breaks
   $arr = array_splice($arr, 0, 4); // reduce the lines to four
   foreach($arr as $line) { $newStr .= $line; } // store them all in a string
   $newStr .= "...";
} else {
   $newStr = $teststring; // there was less or equal to four rows so to us it'all ok
}