Trying to insert text into a file ABOVE a certain line

问题

I have a text file, more of a users file for a program. Im trying to use PHP to insert new data before groups: in the file. The last user is above this line and i want to insert new users below the last user and above groups: in the file

Ive been tinkering and was trying some things, but i can only get it after that line.

heres what i have

$key = 'groups:';
$newline = 'blackberry';

//copy file to prevent double entry
$file = "data2.yml";
$newfile = "filetemp.txt";
copy($file, $newfile) or exit("failed to copy $file");

//load file into $lines array
 $fc = fopen ($file, "r");
 while (!feof ($fc))
 {
    $buffer = fgets($fc, 4096);
    $lines[] = $buffer;
 }

fclose ($fc);

//open same file and use "w" to clear file
$f=fopen($newfile,"w") or die("couldn't open $file");

/* uncomment to debug */
print_r($lines);
print "
\n";

//loop through array using foreach
foreach($lines as $line)
{
       fwrite($f,$line); //place $line back in file
    if (strstr($line,$key)){ //look for $key in each line
    fwrite($f,$newline."\n");
    } //place $line back in file
}
fclose($f);

copy($newfile, $file) or exit("failed to copy $newfile");
?>

Its a yml file, so i cant add an extra line to post after or it screws up and refuses to run.

thanks!

回答1:

your foreach code should be:

foreach($lines as $line)
{
    if (strstr($line,$key)){ //look for $key in each line
        fwrite($f,$newline."\n"); //insert data before line with key
    } 
    fwrite($f,$line); //place $line back in file
}

This way you will write the new data first then the original data.

来源：https://stackoverflow.com/questions/5106719/trying-to-insert-text-into-a-file-above-a-certain-line

标签

php

fopen

fwrite