Php delete specific line from text file

A user selects a number "$Num = $_POST['Number']" from a drop down to delete a line from a text file. Ex.

Cat
Dog
Mouse

Lets say they chose line 3. How do I delete the line in the file so it just prints:

Cat
Dog

using only the number they chose and not the actual words in the line?

asked May 8, 2017 at 23:31

Cvm192Cvm192

231 silver badge4 bronze badges

1

Use this:

$row_number = 0;    // Number of the line we are deleting
$file_out = file("file.txt"); // Read the whole file into an array

//Delete the recorded line
unset($file_out[$row_number]);

//Recorded in a file
file_put_contents("file.txt", implode("", $file_out));

answered May 8, 2017 at 23:44

5

Table of contents
• How to delete a line from the file with php?
• How to delete a single line in a txt file with php [duplicate]
• How to delete a specific line from a file starting a string in php
• yjajkiew / php-delete-line-in-file Public
• PHP delete or replace a line from a text file
• How to delete a file using PHP ?
• How to delete text from file using preg_replace() function in PHP ?
• C Program to Delete a Specific Line From a Text File
• Using php delete line from txt file.

How to delete a line from the file with php?

$contents = file_get_contents($dir);
$contents = str_replace($line, '', $contents);
file_put_contents($dir, $contents);

 $DELETE = "the_line_you_want_to_delete";

 $data = file("./foo.txt");

 $out = array();

 foreach($data as $line) {
     if(trim($line) != $DELETE) {
         $out[] = $line;
     }
 }

 $fp = fopen("./foo.txt", "w+");
 flock($fp, LOCK_EX);
 foreach($out as $line) {
     fwrite($fp, $line);
 }
 flock($fp, LOCK_UN);
 fclose($fp);  

function remove_line($file, $remove) {
    $lines = file($file, FILE_IGNORE_NEW_LINES);
    foreach($lines as $key => $line) {
        if($line === $remove) unset($lines[$key]);
    }
    $data = implode(PHP_EOL, $lines);
    file_put_contents($file, $data);
}

$contents = file_get_contents($dir);
$new_contents = "";
if (strpos($contents, $id) !== false) { // if file contains ID
    $contents_array = explode(PHP_EOL, $contents);
    foreach ($contents_array as &$record) {    // for each line
        if (strpos($record, $id) !== false) { // if we have found the correct line
            continue; // we've found the line to delete - so don't add it to the new contents.
        } else {
            $new_contents .= $record . "\r"; // not the correct line, so we keep it
        }
    }
    file_put_contents($dir, $new_contents); // save the records to the file
    echo json_encode("Successfully updated record!");
}
else {
    echo json_encode("failed - user ID ". $id ." doesn't exist!");
}

$line=explode("\r\n",$text);
unset($line[0]);
$text=implode("\r\n",$line);

/**
 * Removes the first found line inside the given file.
 *
 * @param string $line The line content to be searched.
 * @param string $filePath Path of the file to be edited.
 * @param bool $removeOnlyFirstMatch Whether to remove only the first match or
 * the whole matches.
 * @return bool If any matches found (and removed) or not.
 *
 * @throw \RuntimeException If the file is empty.
 * @throw \RuntimeException When the file cannot be updated.
 */
function removeLineFromFile(
    string $line,
    string $filePath,
    bool $removeOnlyFirstMatch = true
): bool {
    // You can wrap it inside a try-catch block
    $file = new \SplFileObject($filePath, "r");

    // Checks whether the file size is not zero
    $fileSize = $file->getSize();
    if ($fileSize !== 0) {
        // Read the whole file 
        $fileContent = $file->fread($fileSize);
    } else {
        // File is empty
        throw new \RuntimeException("File '$filePath' is empty");
    }

    // Free file resources
    $file = null;

    // Divide file content into its lines
    $fileLineByLine = explode(PHP_EOL, $fileContent);

    $found = false;
    foreach ($fileLineByLine as $lineNumber => $thisLine) {
        if ($thisLine === $line) {
            $found = true;
            unset($fileLineByLine[$lineNumber]);

            if ($removeOnlyFirstMatch) {
                break;
            }
        }
    }

    // We don't need to update file either if the line not found
    if (!$found) {
        return false;
    }

    // Join lines together
    $newFileContent = implode(PHP_EOL, $fileLineByLine);

    // Finally, update the file
    $file = new \SplFileObject($filePath, "w");
    if ($file->fwrite($newFileContent) !== strlen($newFileContent)) {
        throw new \RuntimeException("Could not update the file '$filePath'");
    }

    return true;
}

// $dir is your filename, as you mentioned
removeLineFromFile($line, $dir);

$fileLineByLine[$lineNumber] = "";
// Or even
$fileLineByLine[$lineNumber] = null;

unset($fileLineByLine[$key]);

$file = fopen("path/to/file", "a+");
// remove 2nd and 3rd lines (line numbers are one-based)
fremove_line($file, 2, 3);
fclose($file);

/**
 * Remove the lines with the given `$line_number` from the `$file`.
 * 
 * Example:
 * ```php
 * $file = fopen("path/to/file", "a+");
 * // remove lines 1 and 2
 * fremove_line($file, 1, 2);
 * fclose($file);
 * ```
 * 
 * @param resource $file The file resource opened by `fopen()`
 * @param int ...$line_number The one-based line number(s) to remove, if the
 *     line does not exist, it is ignored
 * 
 * @return boolean True on success, false on failure
 */
function fremove_line($file, int ...$line_number): bool{
    // set the pointer to the start of the file
    if(!rewind($file)){
        return false;
    }

    // get the stat for the full size to truncate the file later on
    $stat = fstat($file);
    if(!$stat){
        return false;
    }

    $current_line = 1; // change to 0 for zero-based $line_number
    $byte_offset = 0;
    while(($line = fgets($file)) !== false){
        // the bytes of the lines ("number of ASCII chars")
        $line_bytes = strlen($line);

        if($byte_offset > 0){
            // move lines upwards
            // go back the `$byte_offset`
            fseek($file, -1 * ($byte_offset + $line_bytes), SEEK_CUR);
            // move the line upwards, until the `$byte_offset` is reached
            if(!fwrite($file, $line)){
                return false;
            }
            // set the file pointer to the current line again, `fwrite()` added `$line_bytes`
            // already
            fseek($file, $byte_offset, SEEK_CUR);
        }

        if(in_array($current_line, $line_number)){
            // the `$current_line` should be removed so save to skip the number of bytes 
            $byte_offset += $line_bytes;
        }

        // keep track of the current line
        $current_line++;
    }

    // remove the end of the file
    return ftruncate($file, $stat["size"] - $byte_offset);
}

file_put_contents($filename, str_replace($line . "\r\n", "", file_get_contents($filename)));

How to delete a single line in a txt file with php [duplicate]

[email protected],
[email protected],
[email protected],
[email protected],
[email protected],
[email protected],
[email protected],
[email protected],

$content = file_get_contents('database-email.txt');
$content = str_replace('[email protected],', '', $content);
file_put_contents('database-email.txt', $content);

 $emailToRemove = "[email protected]";
 $contents = file('database-email.txt'); //Read all lines
 $contents = array_filter($contents, function ($email) use ($emailToRemove) {
      return trim($email, " \n\r,") != $emailToRemove;
 }); // Filter out the matching email
 file_put_contents('database-email.txt', implode("\n", $contents)); // Write back

$emailToRemove = "[email protected]";
$fh = fopen('database-email.txt', "r"); //Current file
$fout = fopen('database-email.txt.new', "w"); //New temporary file
while (($line = fgets($fh)) !== null) {
      if (trim($line," \n\r,") != $emailToRemove) {
         fwrite($fout, $line, strlen($line)); //Write to new file if needed
      } 
}
fclose($fh);
fclose($fout);

unlink('database-email.txt');  //Delete old file 
rename('database-email.txt.new', 'database-email.txt'); //New file is old file

 $DELETE = "[email protected]";

 $data = file("database-email.txt");

 $out = array();

 foreach($data as $line) {
     if(trim($line) != $DELETE) {
         $out[] = $line;
     }
 }

 $fp = fopen("database-email.txt", "w+");
 flock($fp, LOCK_EX);
 foreach($out as $line) {
     fwrite($fp, $line);
 }
 flock($fp, LOCK_UN);
 fclose($fp); 

$data = "";
$emailsToRemove = ["[email protected]" , "[email protected]"];

//open to read
$f = fopen('databse-email.txt','r');
while ($line = fgets($f)) {
    $emailWithComma = $line . ",";

    //check if email marked to remove
    if(in_array($emailWithComma , $emailsToRemove))
        continue;

    $data = $data . $line;
}

fclose($f);


//open to write
$f = fopen('databse-email.txt','w');
fwrite($f, $data);
fclose($fh);

$file = "file_name.txt";
$search_for = "example_for_remove";
$file_data = file_get_contents($file);
$pattern = "/$search_for/mi";
$file_data_after_remove_word = preg_replace($pattern, '', $file_data);
$file_data_after_remove_blank_line = preg_replace("/(^[\r\n]*|[\r\n]+)[\s\t]*[\r\n]+/", "\n", $file_data_after_remove_word);
file_put_contents($file,$file_data_after_remove_blank_line);

How to delete a specific line from a file starting a string in php

abc samle sample
this abc sample
xyz test sample sample

abc samle sample
xyz test sample sample

 $line) {

        //removing the line
        if(stristr($line,$term)!== false){unset($arr[$key]);break;}
    }

    //reindexing array
    $arr = array_values($arr);

    //writing to file
    file_put_contents($f, implode($arr));
?>

yjajkiew / php-delete-line-in-file Public

       DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
               Version 1, August 2012

          Yann Jajkiewicz <[email protected]>

Everyone is permitted to copy and distribute verbatim or modified
copies of this program.

        DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
 TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION

0. You just DO WHAT THE FUCK YOU WANT TO.

PHP delete or replace a line from a text file

while(!feof($file))
  {

$data=fgets($file)."
";

$data1="++ gateway1";

if($data==$data1)
{
echo "found";
}

}

How to delete a file using PHP ?

unlink( $filename, $context );

gfg.txt has been deleted

Warning: unlink() expects parameter 1 to be a valid path, resource
given in C:\xampp\htdocs\server.php on line 12
Resource id #3 cannot be deleted due to an error

How to delete text from file using preg_replace() function in PHP ?

preg_replace( $pattern,  $replacement, $subject);

mango
apple
papaya
guava
apple
grapes
mango
apple

File contents before using preg_replace() function
mango apple papaya guava apple grapes mango apple

File contents after using preg_replace() function

File contents before using preg_replace() function
mango apple papaya guava apple grapes mango apple

File contents after using preg_replace() function
mngo pple ppy guv pple grpes mngo pple

File contents before using preg_replace() function
mango apple papaya guava apple grapes mango apple

File contents after using preg_replace() function
mango papaya guava grapes mango

C Program to Delete a Specific Line From a Text File

#include 
      int main() {
        FILE *fp1, *fp2;
        //consider 40 character string to store filename
        char filename[40];
        char c;
        int del_line, temp = 1;
        //asks user for file name
        printf("Enter file name: ");
        //receives file name from user and stores in 'filename'
        scanf("%s", filename);
        //open file in read mode
        fp1 = fopen(filename, "r");
        c = getc(fp1);
        //until the last character of file is obtained
        while (c != EOF)
        {
          printf("%c", c);
          //print current character and read next character
          c = getc(fp1);
        }
        //rewind
        rewind(fp1);
        printf(" \n Enter line number of the line to be deleted:");
        //accept number from user.
        scanf("%d", &del_line);
        //open new file in write mode
        fp2 = fopen("copy.c", "w");
        c = getc(fp1);
        while (c != EOF) {
          c = getc(fp1);
          if (c == '\n')
          temp++;
          //except the line to be deleted
          if (temp != del_line)
          {
            //copy all lines in file copy.c
            putc(c, fp2);
          }
        }
        //close both the files.
        fclose(fp1);
        fclose(fp2);
        //remove original file
        remove(filename);
        //rename the file copy.c to original name
        rename("copy.c", filename);
        printf("\n The contents of file after being modified are as  follows:\n");
        fp1 = fopen(filename, "r");
        c = getc(fp1);
        while (c != EOF) {
            printf("%c", c);
            c = getc(fp1);
        }
        fclose(fp1);
        return 0;
      }

Using php delete line from txt file.

";
 
		$myFile = 'filterlist.txt';
		//echo $myFile."

";
		
		file_put_contents($myFile, $newWord . PHP_EOL, FILE_APPEND) or die("can't open file");
		
		/*$fh = fopen($myFile, 'a') or die("can't open file");
		
		$stringData = $newWord;
		fwrite($fh, $stringData);*/
		
		//fclose($fh);
		echo "New Word Successfully added to Bad Word Filter List.";
		echo "";
 
	}
	else 
{
		
	echo "Bad Word Filter
";
 
	echo "
";
	
	
	echo "
Add New Word to Filtered List:
";
	echo "
";
	echo "
";
echo "
";
$myFile = "filterlist.txt";
$fh = fopen($myFile, 'r');
$theData = implode(', ', file($myFile));
 
 
$lines = file('filterlist.txt');
echo "
Current List:  

";
// Loop through our array, show HTML source as HTML source; and line numbers too.
 
foreach ($lines as $line_num => $line) 
{
	echo "Word #{$line_num} : " . htmlspecialchars($line) . "
\n";
}
 
// Another example, let's get a web page into a string.  See also file_get_contents().
$html = implode('', file('filterlist.txt'));
 
//$theData = implode(",", fread($fh, filesize($myFile)));
fclose($fh);
 
echo "
Current List:  ".$theData;		
}
 
?>

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