Close open HTML tags in a string

Question 1

Situation is a string that results in something like this:

<p>This is some text and here is a <strong>bold text then the post stop here....</p>

Because the function returns a teaser (summary) of the text, it stops after certain words. Where in this case the tag strong is not closed. But the whole string is wrapped in a paragraph.

Is it possible to convert the above result/output to the following:

<p>This is some text and here is a <strong>bold text then the post stop here....</strong></p>

I do not know where to begin. The problem is that.. I found a function on the web which does it regex, but it puts the closing tag after the string.. therefore it won't validate because I want all open/close tags within the paragraph tags. The function I found does this which is wrong also:

<p>This is some text and here is a <strong>bold text then the post stop here....</p></strong>

I want to know that the tag can be strong, italic, anything. That's why I cannot append the function and close it manually in the function. Any pattern that can do it for me?

Question 2

Here is a function i've used before, which works pretty well:

function closetags($html) {
    preg_match_all('#<(?!meta|img|br|hr|inputb)b([a-z]+)(?: .*)?(?<![/|/ ])>#iU', $html, $result);
    $openedtags = $result[1];
    preg_match_all('#</([a-z]+)>#iU', $html, $result);
    $closedtags = $result[1];
    $len_opened = count($openedtags);
    if (count($closedtags) == $len_opened) {
        return $html;
    }
    $openedtags = array_reverse($openedtags);
    for ($i=0; $i < $len_opened; $i++) {
        if (!in_array($openedtags[$i], $closedtags)) {
            $html .= '</'.$openedtags[$i].'>';
        } else {
            unset($closedtags[array_search($openedtags[$i], $closedtags)]);
        }
    }
    return $html;
}

Personally though, I would not do it using regexp but a library such as Tidy. This would be something like the following:

$str = '<p>This is some text and here is a <strong>bold text then the post stop here....</p>';
$tidy = new Tidy();
$clean = $tidy->repairString($str, array(
    'output-xml' => true,
    'input-xml' => true
));
echo $clean;

Question 3

You can break each data by - and build the array in as much as needed. Notice the use of & in the code as using reference to result array.

Example:

$str = "15-02-01-0000,15-02-02-0000,15-02-03-0000,15-02-04-0000,15-02-05-0000,15-02-10-0000,15-02-10-9100,15-02-10-9101,15-15-81-0000,15-15-81-0024";
$arr = explode(",", $str);
$res = [];
foreach($arr as $e) { // for each line in your data
    $a = explode("-", $e); //break to prefix
    $current = &$res; 
    while(count($a) > 1) { // create the array to that specific place if needed
        $key = array_shift($a); // take the first key
        if (!isset($current[$key])) // if the path not exist yet create empty array 
            $current[$key] = array();
        $current = &$current[$key];
    }
    $current[] = $e; // found the right path so add the element
}

The full result will be in $res.

Question 4

correct me if i'm wrong, but i don't think you can do this with a simple regexp. in a full regexp implementation you could use something like this :

$parts = preg_split("/(?<!<[^>]*)./", $input);

but php does not allow non-fixed-length lookbehind, so that won't work. apparently the only 2 that do are jgsoft and the .net regexp. Useful Page

my method of dealing with this would be :

function splitStringUp($input, $maxlen) {
    $parts = explode(".", $input);
    $i = 0;
    while ($i < count($parts)) {
        if (preg_match("/<[^>]*$/", $parts[$i])) {
            array_splice($parts, $i, 2, $parts[$i] . "." . $parts[$i+1]);
        } else {
            if ($i < (count($parts) - 1) && strlen($parts[$i] . "." . $parts[$i+1]) < $maxlen) {
                array_splice($parts, $i, 2, $parts[$i] . "." . $parts[$i+1]);
            } else {
                $i++;
            }
        }
    }
    return $parts;
}

you didn't mention what you want to happen when an individual sentence is >8000 chars long, so this just leaves them intact.

sample output :

splitStringUp("this is a sentence. this is another sentence. this is an html <a href="a.b.c">tag. and the closing tag</a>. hooray", 8000);
array(1) {
  [0]=> string(114) "this is a sentence. this is another sentence. this is an html <a href="a.b.c">tag. and the closing tag</a>. hooray"
}

splitStringUp("this is a sentence. this is another sentence. this is an html <a href="a.b.c">tag. and the closing tag</a>. hooray", 80);
array(2) {
  [0]=> string(81) "this is a sentence. this is another sentence. this is an html <a href="a.b.c">tag"
  [1]=> string(32) " and the closing tag</a>. hooray"
}

splitStringUp("this is a sentence. this is another sentence. this is an html <a href="a.b.c">tag. and the closing tag</a>. hooray", 40);
array(4) {
  [0]=> string(18) "this is a sentence"
  [1]=> string(25) " this is another sentence"
  [2]=> string(36) " this is an html <a href="a.b.c">tag"
  [3]=> string(32) " and the closing tag</a>. hooray"
}

splitStringUp("this is a sentence. this is another sentence. this is an html <a href="a.b.c">tag. and the closing tag</a>. hooray", 0);
array(5) {
  [0]=> string(18) "this is a sentence"
  [1]=> string(25) " this is another sentence"
  [2]=> string(36) " this is an html <a href="a.b.c">tag"
  [3]=> string(24) " and the closing tag</a>"
  [4]=> string(7) " hooray"
}

Question 5

There is a UDF that will do that described here:

User Defined Function to Strip HTML

CREATE FUNCTION [dbo].[udf_StripHTML] (@HTMLText VARCHAR(MAX))
RETURNS VARCHAR(MAX) AS
BEGIN
    DECLARE @Start INT
    DECLARE @End INT
    DECLARE @Length INT
    SET @Start = CHARINDEX('<',@HTMLText)
    SET @End = CHARINDEX('>',@HTMLText,CHARINDEX('<',@HTMLText))
    SET @Length = (@End - @Start) + 1
    WHILE @Start > 0 AND @End > 0 AND @Length > 0
    BEGIN
        SET @HTMLText = STUFF(@HTMLText,@Start,@Length,'')
        SET @Start = CHARINDEX('<',@HTMLText)
        SET @End = CHARINDEX('>',@HTMLText,CHARINDEX('<',@HTMLText))
        SET @Length = (@End - @Start) + 1
    END
    RETURN LTRIM(RTRIM(@HTMLText))
END
GO

Edit: note this is for SQL Server 2005, but if you change the keyword MAX to something like 4000, it will work in SQL Server 2000 as well.

Question 6

You can use a simple regex like this:

public static string StripHTML(string input)
{
   return Regex.Replace(input, "<.*?>", String.Empty);
}

Be aware that this solution has its own flaw. See Remove HTML tags in String for more information (especially the comments of @mehaase)

Another solution would be to use the HTML Agility Pack.
You can find an example using the library here: HTML agility pack - removing unwanted tags without removing content?

Close open HTML tags in a string

Answers

php,regex,string