The PHP's file_get_contents() function can read a entire HTML page into a string.And we can use this function to get a page from internet and to display only the specified area we want,for example :
if a file http://any_page.html has following design elements
and if we want to display only <div class='main'>some content</div> part in our webpage then we need to find out position of string <div class='main'> as the start point and position of string <div class='extra'> as a end point.To do that we need 3 more functions of PHP that are strpos() strlen() and substr().
substr() : Returns the position of the first occurrence of matched string.
(note: there is a difference between strpos() and strrpos() )
strpos() : Returns the portion of string with "strat point" and "length" as parameters.
strlen() : Returns the length of the given string.
now with the knowledge of this functions you can use some function like this
you can't do something like
You can also use this alternative function if you want it's short in code.
if a file http://any_page.html has following design elements
<html>
<body>
<div class='main'>
some content
</div>
<div class='extra'>
some unneeded content
</div>
</body>
</html>
and if we want to display only <div class='main'>some content</div> part in our webpage then we need to find out position of string <div class='main'> as the start point and position of string <div class='extra'> as a end point.To do that we need 3 more functions of PHP that are strpos() strlen() and substr().
substr() : Returns the position of the first occurrence of matched string.
(note: there is a difference between strpos() and strrpos() )
strpos() : Returns the portion of string with "strat point" and "length" as parameters.
strlen() : Returns the length of the given string.
now with the knowledge of this functions you can use some function like this
<?phpNow if you put this function in a separate php file and use it via include() or require() the following function can be used any where in any page like
function get_selected_area($strat_string,$end_string,$page_address)
{
$whole_html = file_get_contents($page_address);
$strat_point = strpos($whole_html,$strat_string) ;
$end_point = strpos($whole_html,$end_string);
$length_of_needed_string = ($end_point - $strat_point) - 1; //because we don't want "<" in the end
$needed_part_of_html = substr($whole_html,$strat_point,$length_of_needed_string);
return $needed_part_of_html;
}
?>
<?phpNOTE: The string chosen for strat and end must satisfy the HTML standards,for example :
echo get_selected_area("<div class='main'>","<div class='extra'>","http://any_page.html");
?>
you can't do something like
<?phpas a HTML page may have several </div> even before the <div class='main'> and this will surely give you some hard time.
echo get_selected_area("<div class='main'>","</div>","http://any_page.html");
?>
You can also use this alternative function if you want it's short in code.
<?php
function get_selected_area($strat_string,$end_string,$page_address)
{
$whole_html = file_get_contents($page_address);
$strat_point = strpos($whole_html,$strat_string) ;
$end_point = strpos($whole_html,$end_string); for($i=$strat_point;$i < $end_point;$i++) $needed_part_of_html = $whole_html[$i];
return $needed_part_of_html;
}
?>
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