PHP HTML code string interception implementation code

And the data given is an HTML code string, such as this:

Zhang San Comments Li Si sharedan article with a long list of things< /a>

When intercepting, you need to intercept the content inside the div tag, and keep the HTML tag, but only process the text in it. For example, I may just intercept the word "李" in "李思", but if I put it on the front end like this, the a tag in front of "李思" will not be closed, so after intercepting, I need to ensure that the HTML syntax is correct.

This problem is really not easy to solve, it made me depressed for two days. Please note that this is just a string, but the content is HTML code and there is no DOM. It would be easier if it were processed on the front end. You can directly obtain the DOM, then process the nodes inside, and finally output things like innerHTML. It doesn't work now, I have to change my mind. The colleague’s idea is this:

Traverse each character of the string. Set a tag, and set it to 1 when it encounters the tag < at the beginning of the tag. The following characters will not be counted, and then start counting after encountering >. When processing the string inside the label, you must first determine whether the current character encoding may be Chinese. Generally speaking, the length of UTF-8 encoded Chinese characters in PHP is 3, so if you encounter a Chinese character encoding , I have to skip two uncounted ones... At this point, my head is starting to get big. Personally, I think this method is very unpleasant. First of all, this kind of exquisite logic is not easy to control, and the length of Chinese generated under UFT-8 encoding may be 3 or 4, so the rigor of the code is questionable.

My personal idea is to use Tidy (please see the PHP manual for specific usage). I studied Tidy yesterday and found that this thing is quite useful. First, convert this string into a Tidy object, like this:

$tidy = tidy_parse_string($str, array(), 'utf8′); // The last one is to set the encoding. Note that this is utf8, not utf- 8. There is no middle connection.

Then get the body in $tidy (because after conversion, $tidy will automatically add tags such as ):

$body = tidy_get_body($tidy);

You can use var_dump at this time If you look at the structure of some $body, you will find that it turns each tag into a corresponding object with corresponding attributes. For example, such as sdf, some attributes corresponding to such a statement are:

name=>”a”
value => “sdf"
child=> array{[0]=>A text node object, value is sdf}
attribute=array{"href"=>"#"}
… ..Other attributes

As you can see, we can actually process the value of the text node under the node corresponding to the a tag separately, so that it will not destroy any HTML integrity. Originally, I thought that after changing the value of the text node in the a label, the value of the a label would also change accordingly. In that case, it would be OK if I directly returned the value of the node corresponding to the a label. I didn't expect it to be like that. Alas, so I processed the text in it. Then you still have to spell out the new HTML yourself.

After knowing the structure of the Tidy object, everything is easy to handle. Just traverse all the nodes. For this requirement, it is to find the div tag and start processing the nodes inside. The code is as follows:

if(mb_strwidth($subchild->value, 'utf-8′) >= $len)
{
$subchild->value = mb_strimwidth($subchild->value, 0, $ len, '…', 'utf-8′);
$trimed_str .= $subchild->value;
break;
}
else
{
$trimed_str .= $subchild->value;
$len = $len - mb_strwidth($subchild->value, 'utf-8′);$subchild in
}

is a child node. Note that mb_strwidth is used here to obtain the string length. I strongly recommend this mb_strwidth, it is very useful, it will treat Chinese as two characters in length, which exactly meets the needs here! Moreover, mb_strimwidth is used when intercepting strings. This function will also treat Chinese as two characters in length. The functions starting with mb_ are really easy to use.

I won’t write out the specific code, because it is written based on a requirement and is not made into a universal form. One day I have time to make it universal and publish it.

In addition, it is a pity that FireFox does not support the text-overflow attribute, otherwise there would be no need to work so hard in the background to truncate it. If you have a better method, you can leave a message for discussion. For more related articles, please pay attention to the PHP Chinese website (www.php.cn)!