Shortening a String

ganeshcp

Hi,
I want to shorten a string to a given length, after a whitespace....
I found this fuction to do so

function shorten ($var, $len = 120)
{
       if (empty ($var)) {
               return "";
       }
       if (strlen ($var) < $len) {
               return $var;
       }

   if (preg_match ("/(.{1,$len})\s/", $var, $match)) {
           return $match [1] . "...";
   }
   else {
           return substr ($var, 0, $len) . "...";
   }
}

But it doesn't seem to work correctly. NO matter what the value of $len is it always cuts the string to a fixed length.

I'm working with articles/interviews which i want to put in separate pages, so my $len is like 7000 ...

laserlight

What do you mean by "shorten to a string to a given length at a whitespace"?

ganeshcp

Sorry let me explain...

If there's a long text:
He sees to it that his artistes are themselves most of the time. I am grateful to him for teaching me the art of being myself while performing. His style is very different and in a subtle way he taps your potential.

Now if I want to shorten it to X lenght it wud become:

He sees to it that his artistes are themselves most of the...

If I just use substr function it might become:

He sees to it that his artistes are themselves most of t...

which looks odd.. So I want to shorten the string at a white space....

leatherback

Hi,

How about this:

Use substr to get the minium desired length. and again to get the remainder of the string. (I was actually trying to find a split function.. Doesn't that exist?)

Then use explode() by " " to split the remainder into pieces.

Then:

$ouput = $firstpart.$explodedtext[0];

rpanning

I've wipped up this function for ya, give it a try. The function takes two artuments, the string to be shortend and the length to be shortened to. Right below the function is an example which will reproduce what you wanted in your second post. If you have any questions on how it works just let me know. 🙂

//////////////////  Use My Second Function Or Weeds  ///////////////////
//////  It'll work better but I'll leave this one up for keep sake  //////

function str_shorten($str, $len, $end='...')
{
    if ($len < strlen($str)) {
        for ($i=$len; $i>0; $i--) {
            if (ctype_space($str{$i}))
                break;
        }
        $short = substr($str, 0, $i) . $end;
    } else
        $short = $str;
    return($short);
}
$article = 'He sees to it that his artistes are themselves most of the time. 
I am grateful to him for teaching me the art of being myself while performing. 
His style is very different and in a subtle way he taps your potential.';
// Print out an example of the str_cut function and then just substr the article (to show the diff).
print(str_shorten($article, 56) . "<br>\n" . substr($article, 0, 56));

Edit: I changed a few things in the function, just to clean it up. The name is now str_shorten instead of str_cut (sounds nicer). The length is now required (no default). And there is an added optional argument to change the ending string ('...' is the default). Finaly, the loop goes backwards to find a space so your max length is truely a max number.

leatherback

Hi Rpannin,

Great solution!

Just a quick question.. is ctype_space() a PhP included function? I cannot find it in the PhP manual..
Or is it a function your wrote for yourself?

Tha.

rpanning

LOL, actualy I found it in the manual while looking for a char to ascii function. I didn't know it existed...but, here it is. 😃

Weedpacket

Sorry, I was just wondering why the loop.

function str_cut($str, $len=50)
{	if(strlen($str)<=$len) return $str; // Waste of time continuing

// We need to check to see if we ended on the end of a word. If we did, we
// won't need to do any more truncation.
// For that we need to see what the _next_
// character after the end was
$trailing_char=$str{$len};

// Initial guess at shorter string.
$str = substr($str,0,$len);

if($trailing_char==' ') // We ended on the end of the word
	return $str;
if($str{$len-1}==' ') // We ended after a space
	return rtrim($str);


$last_space=strrpos($str, ' ');
if($last_space===false) // No spaces in the string!
	return $str; // Can't do better than this

// Lop off broken last word
$str=substr($str,0,$last_space);
return rtrim($str);
}

Of course, the drawback is that that only matches spaces: other forms of whitespace, or punctuation marks, therefore count as "word" characters.

rpanning

First note the changes to my first post. I made a few changes to the function, see the edit msg.

Hi Weedpacket, if your going to go with that route why do the first couple of if statements?

string str_shorten ( string text, int max_length[, string ending])

Function operation: If the string is already shorter than what is to be cut, just return the string. Else, cut the string to the max length. Next, check to see if the cut string ended or ends with a space, return cut str if so. Else, try and find the last space. If found, shorten the cut string to the space. Else, just return the cut string (user is expecting the string be shorter than the max length).

function str_shorten($str, $len, $end='...')
{
    if ($len < strlen($str)) {
        $cut = substr($str, 0, $len);
        if ($str{$len} == ' ')
            $short = $cut . $end;
        elseif ($str{$len-1} == ' ')
            $short = rtrim($cut) . $end;
        elseif (($space = strrpos($cut, ' ')) !== false)
            $short = substr($cut, 0, $space) . $end;
        else
            $short = $cut . $end;
    } else
        $short = $str;
    return($short);
}

rpanning

Ok, I looked at your code again and see why you use if($trailing_char==' ') return $str. I've added that to my function above which is basicly the same as yours. But, why the if($str{$len-1}==' ') return rtrim($str);? That will be taken care of in the strrpos($str, ' ') will it not?

Weedpacket

Yep, but it's faster.

    if($str{$len-1}==' ') // We ended after a space
        return rtrim($str);

When we pick the initial place for the cut, we have to look on both sides to see whether or not there are spaces there. If there's a space on either side then our cut is in a good place, because it's on a word boundary. Otherwise, the cut was in the middle of the word and we have to lop off that broken word.

We don't need to do any further searching to decide this, because we already which characters to look at. Taking the time out to look at one character of a string is offset by the fact we don't then need to use strrpos something like 20-25% of the time (in English).

rpanning

Ok, now I see. Again, I've made that change in my function above. Now it's almost exacly your function (🙂) with one diff. rtrim at the end, what is that for? The space should have been taken off with the substr.

ganeshcp ya getting any of this? lol I havn't seen you online or posting for a while. Weed and my functions are basicly the same so you can use either one to get the same effect.

Weedpacket

Originally posted by rpanning
Ok, now I see. Again, I've made that change in my function above. Now it's almost exacly your function (🙂) with one diff. rtrim at the end, what is that for? The space should have been taken off with the substr.

You're right; that probably is unnecessary - it went in originally but doesn't really need to stay; only if there were ever multiple consecutive spaces would it make a difference.

ganeshcp

rpanning thanks a lot for the function!! Sorry for the late reply...I was juz trying to use the same function along with a position variable so that when users click on "...read more" they can see the next page of the article! Sounds tough...if I get stuck I knw where to go hehe 🙂
G

Shrike

Hmm this all seems very complicated for what must be a simple task.

$string = "a string much longer than this one";
$stringparts = preg_split("/^.{50}.*?\\b/", $string);
echo substr($string, 0, strlen($string)-strlen($stringparts[1]));

Untested, but maybe you get the idea 🙂

Weedpacket

Originally posted by Shrike
Hmm this all seems very complicated for what must be a simple task.
$string = "a string much longer than this one";
$stringparts = preg_split("/^.{50}.*?\\b/", $string);
echo substr($string, 0, strlen($string)-strlen($stringparts[1]));
Untested, but maybe you get the idea 🙂 [/B]

Looks expensive; and doesn't shorten the string if it breaks a word, but lengthens it instead.

Shrike

My regexp isn't up to much but I'm pretty sure it can be done with a backreference somehow 🙂

Weedpacket

I still think my two substrs, one strlen, and a strrpos (in the worst case) beats your two strlens, one substr, and a preg_split (in every case) 🙂

Shrike

I just like short code...doesn't everyone have ultrasparcs to run their servers on?