File Handling using PHP - php

Question

Can anyone tell the method to modify/delete the contents of a text file using PHP

Answer 1

Using file_put_contents:
file_put_contents($filename, 'file_content');
If you want to append to the file instead of replacing it's contents use:
file_put_contents($filename, 'append_this', FILE_APPEND);
(file_out_contents is the simpler alternative to using the whole fopen complex.)

Answer 2

By using fopen:
if (is_writable($filename)) {
if (!$handle = fopen($filename, 'w')) {
echo "Cannot open file ($filename)";
exit;
}
if (fwrite($handle, $somecontent) === FALSE) {
echo "Cannot write to file ($filename)";
exit;
}
echo "Success, wrote to file ($filename)";
fclose($handle);
}
Write "" to a file to delete its contents.
To delete contents line by line use:
$arr = file($fileName);
unset($arr[3]); // 3 is an arbitrary line
then write the file contents. Or are you referring to memory mapped files?

Answer 3

There are number of ways to read files. Large files can be handled very fast using
$fd = fopen ("log.txt", "r"); // you can use w/a switches to write append text
while (!feof ($fd))
{
$buffer = fgets($fd, 4096);
$lines[] = $buffer;
}
fclose ($fd);
you can also use file_get_contents() to read files. its short way of achieving same thing.
to modify or append file you can use
$filePointer = fopen("log.txt", "a");
fputs($filePointer, "Text HERE TO WRITE");
fclose($filePointer);
YOU CAN ALSO LOAD THE FILE INTO ARRAY AND THEN PERFORM SEARCH OPERATION TO DELETE THE SPECIFIC ELEMENTS OF THE ARRAY.
$lines = file('FILE WITH COMPLETE PATH.'); // SINGLE SLASH SHOULD BE DOUBLE SLASH IN THE PATH SOMTHING LIKE C://PATH//TO//FILE.TXT
Above code will load the file in $lines array.