php中常用字符串处理代码片段整理

$text = strip_tags($input, "");

function GetBetween($content,$start,$end){
$r = explode($start, $content);
if (isset($r[1])){
$r = explode($end, $r[1]);
return $r[0];
}
return '';
}

$url = "Jean-Baptiste Jung (https://www.jb51.net)";
$url = preg_replace("#http://([A-z0-9./-]+)#", '<a href="http://www.catswhocode.com/blog/$1" style="font-size: 12px; vertical-align: baseline; background-color: transparent; margin: 0px; padding: 0px; color: #3777af; text-decoration: none; font-weight: bold">$0</a>', $url);

function split_to_chunks($to,$text){
$total_length = (140 - strlen($to));
$text_arr = explode(" ",$text);
$i=0;
$message[0]="";
foreach ($text_arr as $word){
if ( strlen($message[$i] . $word . ' ') <= $total_length ){
if ($text_arr[count($text_arr)-1] == $word){
$message[$i] .= $word;
} else {
$message[$i] .= $word . ' ';
}
} else {
$i++;
if ($text_arr[count($text_arr)-1] == $word){
$message[$i] = $word;
} else {
$message[$i] = $word . ' ';
}
}
}
return $message;
}

$string = preg_replace('/\b(https?|ftp|file):\/\/[-A-Z0-9+&@#\/%?=~_|$!:,.;]*[A-Z0-9+&@#\/%=~_|$]/i', '', $string);

function slug($str){
$str = strtolower(trim($str));
$str = preg_replace('/[^a-z0-9-]/', '-', $str);
$str = preg_replace('/-+/', "-", $str);
return $str;
}

$fh = fopen("contacts.csv", "r");
while($line = fgetcsv($fh, 1000, ",")) {
echo "Contact: {$line[1]}";
}

function contains($str, $content, $ignorecase=true){
if ($ignorecase){
$str = strtolower($str);
$content = strtolower($content);
}
return strpos($content,$str) ? true : false;
}

function String_Begins_With($needle, $haystack {
return (substr($haystack, 0, strlen($needle))==$needle);
}

function extract_emails($str){
// This regular expression extracts all emails from a string:
$regexp = '/([a-z0-9_\.\-])+\@(([a-z0-9\-])+\.)+([a-z0-9]{2,4})+/i';
preg_match_all($regexp, $str, $m);

return isset($m[0]) ? $m[0] : array();
}

$test_string = 'This is a test string...

test1@example.org

Test different formats:
test2@example.org;
<a href="test3@example.org">foobar</a>
<test4@example.org>

strange formats:
test5@example.org
test6[at]example.org
test7@example.net.org.com
test8@ example.org
test9@!foo!.org

foobar
';

print_r(extract_emails($test_string));