Php append to file if the string is unique [closed] - php

Question

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Closed 9 years ago.
Is it possible to check if the string that is being added to file is not already in the file and only then add it? Right now I am using
$myFile = "myFile.txt";
$fh = fopen($myFile, 'a') or die("can't open file");
$stringData = $var . "\n";
fwrite($fh, $stringData);
fclose($fh);
But I get many duplicates of $var values and wanted to get rid of them.
Thank you

Answer 1

use this
$file = file_get_contents("myFile.txt");
if(strpos($file, $var) === false) {
echo "String not found!";
$myFile = "myFile.txt";
$fh = fopen($myFile, 'a') or die("can't open file");
$stringData = $var . "\n";
fwrite($fh, $stringData);
fclose($fh);
}

Answer 2

$myFile = "myFile.txt";
$filecontent = file_get_contents($myFile);
if(strpos($filecontent, $var) === false){
$fh = fopen($myFile, 'a') or die("can't open file");
$stringData = $var . "\n";
fwrite($fh, $stringData);
fclose($fh);
}else{
//string found
}

Answer 3

Best way is use file_get_contents & perform operation only if $var is not in your file.
$myFile = "myFile.txt";
$file = file_get_contents($myFile);
if(strpos($file, $var) === FALSE)
{
$fh = fopen($myFile, 'a') or die("can't open file");
$stringData = $var . "\n";
fwrite($fh, $stringData);
fclose($fh);
}

Answer 4

Possible solution could be :
1. Fetch the contents using fread or file_get_contents
2. Compare the contents with the current contents in file
3. add it if it is not there.

Answer 5

function find_value($input) {
$handle = #fopen("list.txt", "r");
if ($handle) {
while (!feof($handle)) {
$entry_array = explode(":",fgets($handle));
if ($entry_array[0] == $input) {
return $entry_array[1];
}
}
fclose($handle);
}
return NULL;
}
You can do the it like this also
$content = file_get_contents("titel.txt");
$newvalue = "word-searching";
//Then use strpos to find the text exist or not

Answer 6

you could save all your added string in an array and the check with in_array if the current string has been added or not.
Second choice is to read the file each time you want to write and do a strstr on it.

Answer 7

I believe fgets is the answer here.
$handle = fopen($path, 'r+'); // open the file for r/w
while (!feof($handle)) { // while not end
$value = trim(fgets($handle)); // get the trimmed line
if ($value == $input) { // is it the value?
return; // if so, bail out
} //
} // otherwise continue
fwrite($handle, $input); // hasn't bailed, good to write
fclose($handle); // close the file
This answer is based solely on the fact that you have appended a newline ("\n") in your code, which is why fgets will work here. This may be preferable over pulling the whole file into memory with file_get_contents(), simply because the size of the file may be prohibitive of that.
Alternatively, if the values are not newline delimited, but are fixed length, you can always use the $length argument of fgets() to pull exactly $n characters out (or use fread() to pull exactly $n bytes out)