php不破坏单词截取子字符串

/*

snippet(phrase,[max length],[phrase tail])

snippetgreedy(phrase,[max length before next space],[phrase tail])

*/

function snippet($text,$length=64,$tail="...") {

$text = trim($text);

$txtl = strlen($text);

if($txtl > $length) {

for($i=1;$text[$length-$i]!=" ";$i++) {

if($i == $length) {

return substr($text,0,$length) . $tail;

}

}

$text = substr($text,0,$length-$i+1) . $tail;

}

return $text;

}

// It behaves greedy, gets length characters ore goes for more

function snippetgreedy($text,$length=64,$tail="...") {

$text = trim($text);

if(strlen($text) > $length) {

for($i=0;$text[$length+$i]!=" ";$i++) {

if(!$text[$length+$i]) {

return $text;

}

}

$text = substr($text,0,$length+$i) . $tail;

}

return $text;

}

// The same as the snippet but removing latest low punctuation chars,

// if they exist (dots and commas). It performs a later suffixal trim of spaces

function snippetwop($text,$length=64,$tail="...") {

$text = trim($text);

$txtl = strlen($text);

if($txtl > $length) {

for($i=1;$text[$length-$i]!=" ";$i++) {

if($i == $length) {

return substr($text,0,$length) . $tail;

}

}

for(;$text[$length-$i]=="," || $text[$length-$i]=="." || $text[$length-$i]==" ";$i++) {;}

$text = substr($text,0,$length-$i+1) . $tail;

}

return $text;

}

/*

echo(snippet("this is not too long to run on the column on the left, perhaps, or perhaps yes, no idea") . "
");

echo(snippetwop("this is not too long to run on the column on the left, perhaps, or perhaps yes, no idea") . "
");

echo(snippetgreedy("this is not too long to run on the column on the left, perhaps, or perhaps yes, no idea"));

*/