If the loaded file is particularly large, such as hundreds of M, on G, then performance down, then PHP has no large file processing functions or classes? The answer is: yes.
PHP is really more and more "object-oriented", some of the original basis of the SPL methods are beginning to realize class.
Starting with the PHP 5.1.0, the SPL library adds Splfileobject and splfileinfo two standard file operation classes. Splfileinfo is implemented from the PHP 5.1.2.
In the literal sense, it can be seen that splfileobject is more powerful than splfileinfo.
Yes, Splfileinfo is used only to get some property information about a file, such as file size, file access time, file modification time, suffix name equivalence, and Splfileobject is inherited splfileinfo these features.
Copy Code code as follows:
/** returns the contents of the file from line x to row y (support php5, PHP4)
* @param string $filename filename
* Number of lines @param int $startLine start
* Number of lines @param int $endLine end
* @return String
*/
function Getfilelines ($filename, $startLine = 1, $endLine =50, $method = ' rb ') {
$content = Array ();
$count = $endLine-$startLine;
Determine the PHP version (because you want to use splfileobject,php>=5.1.0)
if (Version_compare (php_version, ' 5.1.0 ', ' >= ')) {
$fp = new Splfileobject ($filename, $method);
$FP->seek ($startLine-1);//go to Nth row, the Seek method parameter counts starting from 0
for ($i = 0; $i <= $count; + + $i) {
$content []= $fp->current ()//current () get the contents of the line
$FP->next ()//Next line
}
}else{//php<5.1
$fp = fopen ($filename, $method);
if (! $fp) return to ' Error:can not read file ';
For ($i =1 $i < $startLine + + $i) {//Skip front $startline Line
Fgets ($FP);
}
for ($i; $i <= $endLine; + + $i) {
$content []=fgets ($FP);//Read file line contents
}
Fclose ($FP);
}
Return Array_filter ($content); Array_filter filter: False,null, "
}
Ps: None of the above "read to the end of the judgment":! $fp->eof () or!feof ($FP), coupled with this judgment impact efficiency, you add a lot of tests and many many lines of running time to know, and there is absolutely no need to add.
You can see from the above function that the use of splfileobject is much faster than the fgets below, especially if the number of rows is very high, and to take the later content. Fgets to two cycles to be able to, and to cycle $endline times.
This method took a lot of effort, testing a lot of writing, is to get the most efficient method. Who feel that there is merit to improve the welcome enlighten.
Use to return 35270 rows-35280 lines of content:
Copy Code code as follows:
Echo ' <pre> ';
Var_dump (Getfilelines (' test.php ', 35270,35280));
Echo ' </pre> ';
