I'm making this program and I'm trying to find out how to write data to the beginning of a file rather than the end. "a"/append only writes to the end, how can I make it write to the beginning? Because "r+" does it but overwrites the previous data.
$datab = fopen('database.txt', "r+");
Here is my whole file:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<title>Facebook v0.1</title>
<style type="text/css">
#bod{
margin:0 auto;
width:800px;
border:solid 2px black;
}
</style>
</head>
<body>
<div id="bod">
<?php
$fname = $_REQUEST['fname'];
$lname = $_REQUEST['lname'];
$comment = $_REQUEST['comment'];
$datab = $_REQUEST['datab'];
$gfile = $_REQUEST['gfile'];
print <<<form
<table border="2" style="margin:0 auto;">
<td>
<form method="post" action="">
First Name :
<input type ="text"
name="fname"
value="">
<br>
Last Name :
<input type ="text"
name="lname"
value="">
<br>
Comment :
<input type ="text"
name="comment"
value="">
<br>
<input type ="submit" value="Submit">
</form>
</td>
</table>
form;
if((!empty($fname)) && (!empty($lname)) && (!empty($comment))){
$form = <<<come
<table border='2' width='300px' style="margin:0 auto;">
<tr>
<td>
<span style="color:blue; font-weight:bold;">
$fname $lname :
</span>
$comment
</td>
</tr>
</table>
come;
$datab = fopen('database.txt', "r+");
fputs($datab, $form);
fclose($datab);
}else if((empty($fname)) && (empty($lname)) && (empty($comment))){
print" please input data";
} // end table
$datab = fopen('database.txt', "r");
while (!feof($datab)){
$gfile = fgets($datab);
print "$gfile";
}// end of while
?>
</div>
</body>
</html>
The quick and dirty:
<?php
$file_data = "Stuff you want to add\n";
$file_data .= file_get_contents('database.txt');
file_put_contents('database.txt', $file_data);
?>
If you don't want to load the entire contents of the file into a variable, you can use PHP's Streams feature:
function prepend($string, $orig_filename) {
$context = stream_context_create();
$orig_file = fopen($orig_filename, 'r', 1, $context);
$temp_filename = tempnam(sys_get_temp_dir(), 'php_prepend_');
file_put_contents($temp_filename, $string);
file_put_contents($temp_filename, $orig_file, FILE_APPEND);
fclose($orig_file);
unlink($orig_filename);
rename($temp_filename, $orig_filename);
}
What this does is writes the string you want to prepend to a temporary file, then writes the contents of the original file to the end of the temporary file (using streams instead of copying the whole file into a variable), and finally removes the original file and renames the temporary file to replace it.
Note: This code was originally based on a now-defunct blog post by Chao Xu. The code has since diverged, but the original post can be viewed in the Wayback Machine.
I think what you can do is first read the content of the file and hold it in a temporary variable, now insert the new data to the beginning of the file before also appending the content of the temporary variable.
$file = file_get_contents($filename);
$content = 'Your Content' . $file;
file_put_contents($content);
Open a file in w+ mode not a+ mode.
Get the length of text to add ($chunkLength)
set a file cursor to the beginning of the file if needed
read $chunkLength bytes from the file
return the cursor to the $chunkLength * $i;
write $prepend
set $prepend a value from step 4
do these steps, while EOF
$handler = fopen('1.txt', 'w+');//1
rewind($handler);//3
$prepend = "I would like to add this text to the beginning of this file";
$chunkLength = strlen($prepend);//2
$i = 0;
do{
$readData = fread($handler, $chunkLength);//4
fseek($handler, $i * $chunkLength);//5
fwrite($handler, $prepend);//6
$prepend = $readData;//7
$i++;
}while ($readData);//8
fclose($handler);
You can use the following code to append text at the beginning and end of the file.
$myFile = "test.csv";<br>
$context = stream_context_create();<br>
$fp = fopen($myFile, 'r', 1, $context);<br>
$tmpname = md5("kumar");<br>
//this will append text at the beginning of the file<br><br>
file_put_contents($tmpname, "kumar");<br>
file_put_contents($tmpname, $fp, FILE_APPEND);<br>
fclose($fp);<br>
unlink($myFile);<br>
rename($tmpname, $myFile);<br><br>
//this will append text at the end of the file<br>
file_put_contents($myFile, "ajay", FILE_APPEND);
You can use fseek to change the pointer in the note.
It has to be noted that if you use fwrite it will erase the current content. So basically you have to read the whole file, use fseek, write your new content, write the old data of the file.
$file_data = file_get_contents('database.txt')
$fp = fopen('database.txt', 'a');
fseek($fp,0);
fwrite($fp, 'new content');
fwrite($fp, $file_data);
fclose($fp);
If your file is really huge and you don't want to use too much memory, you might want to have two file approach like
$fp_source = fopen('database.txt', 'r');
$fp_dest = fopen('database_temp.txt', 'w'); // better to generate a real temp filename
fwrite($fp_dest, 'new content');
while (!feof($fp_source)) {
$contents .= fread($fp_source, 8192);
fwrite($fp_dest, $contents);
}
fclose($fp_source);
fclose($fp_dest);
unlink('database.txt');
rename('database_temp.txt','database.txt');
The solution of Ben seems to be more straightforward in my honest opinion.
One last point: I don't know what you are stocking in database.txt but you might do the same more easily using a database server.
One line:
file_put_contents($file, $data."\r\n".file_get_contents($file));
Or:
file_put_contents($file, $data."\r\n --- SPLIT --- \r\n".file_get_contents($file));
This code remembers data from the beginning of the file to protect them from being overwritten. Next it rewrites the all the data existing in file chunk by chunk.
$data = "new stuff to insert at the beggining of the file";
$buffer_size = 10000;
$f = fopen("database.txt", "r+");
$old_data_size = strlen($data);
$old_data = fread($f, $old_data_size);
while($old_data_size > 0) {
fseek($f, SEEK_CUR, -$old_data_size);
fwrite($f, $data);
$data = $old_data;
$old_data = fread($f, $buffer_size);
$old_data_size = strlen($data);
}
fclose($f);
There is no way to write to the beginning of a file like you think. This is I guess due to reason how OS and HDD are seeing the file. It has got a fixed start and expanding end. If you want to add something in the middle or beggining it requires some sliding. If it is a small file just read it all and do your manipulation and write back. But if not, and if you are always adding to the beginning just reverse line order, consider the end as beginning...
file_get_contents() and file_put_contents() use more memory than using the fopen(), fwrite(), and fclose() functions:
$fh = fopen($filename, 'a') or die("can't open file");
fwrite($fh, $fileNewContent);
fclose($fh);
Related
This question already has answers here:
How to delete a line from the file with php?
(10 answers)
Closed last year.
i was wondering if it is posible to delete a single line in a txt file with php.
I am storing emailadresses in a flat txt file named databse-email.txt
I use this code for it:
<?php
if ($_SERVER['REQUEST_METHOD'] == 'POST') {
$email = $_POST['email-subscribe'] . ',' . "\n";
$store = file_put_contents('database-email.txt', $email, FILE_APPEND | LOCK_EX);
if($store === false) {
die('There was an error writing to this file');
}
else {
echo "$email successfully added!";
}
}
?>
Form:
<form action="" method="POST">
<input name="email-subscribe" type="text" />
<input type="submit" name="submit" value="Subscribe">
</form>
The content of the file looks like this:
janny#live.nl,
francis#live.nl,
harry#hotmail.com,
olga#live.nl,
annelore#mail.ru,
igor#gmx.de,
natasha#hotmail.com,
janny.verlinden#gmail.com,
All lines are , seperated
Lets say i want to delete only the emailadres: igor#gmx.de
How can i do that?
What i want to achieve is a unsubscribe form and delete a single line in the .txt file
You can use str_replace
$content = file_get_contents('database-email.txt');
$content = str_replace('igor#gmx.de,', '', $content);
file_put_contents('database-email.txt', $content);
Because of the way the filesystem works you can't do this in an intuitive way. You have to overwrite the file with all the lines except the one you want to delete, here's an example:
$emailToRemove = "igor#gmx.de";
$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
Here's a streaming alternative solution in the cases where the file does not fit in memory:
$emailToRemove = "igor#gmx.de";
$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
There is also a way to do this in-place to minimize extra disk needed but that is trickier.
You can do it programmatically which will just look over every line and if it not what you want to delete, it gets pushed to an array that will get written back to the file . Like below
$DELETE = "igor#gmx.de";
$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);
first read the file using fopen and fget , and make array to list the emails you want to remove , use in_array to check if value exists in array , and then after remove unwanted emails save the file using fwrite and you need to close the file after the read and the write operations using fclose
checkout this code
$data = "";
$emailsToRemove = ["igor#gmx.de" , "janny#live.nl"];
//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);
for delete special word and next delete blank line try this:
$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);
I want to write a script which reads data from a text file, lets me edit it and then allows me to save the contents to a text file.
I think I can load the file content in a text field to edit the file, though better suggestions are welcome . I want to load 10 lines at a time, edit them and then append them to a single output file
As of now I am just able to read data from the file.
<html>
<body>
<?php
$file = fopen("t.txt", "r");
$i = 0;
while (!feof($file)) {
$line_of_text = fgets($file);
$members = explode('\n', $line_of_text);
var_dump($members);
}
fclose($file);
?>
</body>
</html>
To read in 10 lines at a time, you do the following
$output = '';
$has_content = true;
while ($has_content) {
for ($i = 0; $i < 10; $i++) {
$line = fgets($file);
if (is_null($line)) {
$has_content = false;
break;
}
$processed_line = ...
$output .= $processed_line;
}
}
After closing the readable filehandle, you can write it back to the original file
$fh = fopen("t.txt", "w");
fwrite($fh, $output);
fclose($fh);
You can read entire file a single string using file_get_contents. Also, take a look on related question Read Data From Text File PHP.
So I'm working on a little php file that is supposed to alter a specific file for the user. It gets the contents of the file and puts them into a textarea within a form. How can I make it so any edits done within this textarea will be rewritten to the file on the server? And even better, would I be able to allow the user to only edit certain lines, and have only those lines be rewritten?
Here's my code so far:
<?php
$filename = "../tree_c/index.php";
//$fp = fopen ($filename, "w"); <- doesn't seem to work for it opens empty file.
$contents = file_get_contents($filename);
/*
if (isset($_POST['field'])) {
// something here to rewrite the file.
*/
?>
<form action="<?php echo $_SERVER['PHP_SELF']; ?>" method="POST">
<textarea name="field"><?php echo $contents ?></textarea>
<input type="submit" value="Save">
</form>
This should work fairly easily:
if (isset($_POST['field'])) {
file_put_contents($filename, $_POST['field']);
}
$datafile = "Files.txt";
$fp = fopen($datafile, "r");
$textdata= fgets($fp, 1024);
$text = '"'.$textdata.'"';
$this->set('text',$text);
if(!empty($this->data))
{
$datas = $this->data['data']['text']; //(your Textarea name)
$myFile = "Files.txt";
$fh = fopen($myFile, 'w') or die("can't open file");
fwrite($fh, $datas);
fclose($fh);
}
hope this ll help you....
My friend and I have a little spare time home page together. He's not a programmer, and in order for him to be able to change some text on the front page, I created a php-script that
1) Reads data from file "tester.txt" (this is the text that should go on the front page)
2) Prints this text to a textarea, where you can edit the text and submit it again
3) Writes the edited text to the same file, "tester.txt"
The two functions Read(); and Write(); look like this
function Read() {
$file = "tester.txt";
$fp = fopen($file, "r");
while(!feof($fp)) {
$data = fgets($fp, filesize($file));
echo "$data <br>";
}
fclose($fp);
}
function Write() {
$file = "tester.txt";
$fp = fopen($file, "w");
$data = $_POST["tekst"];
fwrite($fp, $data);
fclose($fp);
}
The only problem I have is that when the text is printed to a text area the line returns are written as <br> - and I don't really want it to do that, because when you edit some of the code and rewrites it, another layer of <br>'s appear. Here's a screenshot to illustrate:
Is there any workaround to this?
Thanks!
If you need the rest of the code, here it is:
<html>
<head>
<title>Updater</title>
</head>
<body>
<?php
function Read() {
$file = "tester.txt";
$fp = fopen($file, "r");
while(!feof($fp)) {
$data = fgets($fp, filesize($file));
echo "$data <br>";
}
fclose($fp);
}
function Write() {
$file = "tester.txt";
$fp = fopen($file, "w");
$data = $_POST["tekst"];
fwrite($fp, $data);
fclose($fp);
}
?>
<?php
if ($_POST["submit_check"]){
Write();
};
?>
<form action="<?php echo $_SERVER['PHP_SELF'] ?>" method="post">
<textarea width="400px" height="400px" name="tekst"><?php Read(); ?></textarea><br>
<input type="submit" name="submit" value="Update text">
<input type="hidden" name="submit_check" value="1">
</form>
<?php
if ($_POST["submit_check"]){
echo 'Text updated';
};
?>
</body>
</html>
This is simpler than you think. You shouldn't be outputting the <br> tags as the textarea already contains the entered newline characters (\r\n or \n). You don't have to read the file like that, if you read it this way, you never have to worry about the character contents.
Change:
$fp = fopen($file, "r");
while(!feof($fp)) {
$data = fgets($fp, filesize($file));
echo "$data <br>";
}
fclose($fp);
to:
echo file_get_contents( $file);
Problem solved.
This is happening because while writing the contents to the text area, you're putting a <br> at the end of each line. But in a textarea line breaks are noted by "\n". When you're saving your existing text, the next time the line breaks are replaced with more <br>.
While printing out the content on a public page, keep the . But in the editing page, remove the br.
Here's what I would have done with the PHP code:
<?php
define("FILE_NAME", "tester.txt");
function Read()
{
echo #file_get_contents(FILE_NAME);
}
;
function Write()
{
$data = $_POST["tekst"];
#file_put_contents(FILE_NAME, $data);
}
?>
<?php
if ($_POST["submit_check"])
{
Write();
}
?>
You use echo "$data <br>"; - just make that echo $data; ?
At a guess, this is hosted on a *nix machine, and he is using a Windows machine to do the editing?
If this is the case, changing your write function to this should solve the problem:
function Write(){
$file = "tester.txt";
$fp = fopen($file, "w");
$data = str_replace(array("\r\n","\r"),"\n",$_POST["tekst"]);
fwrite($fp, $data);
fclose($fp);
};
You don't need the <br>'s. Depending how your <textarea> is configured, by default lines are hard wrapped using \n's. These are preserved when you save the file, therefore you don't need to add your own line breaks.
Use regex to replace the break tag with a newline character
preg_replace('#<br\s*/?>#i', "\n", $data);
You can find a more detailed explanation answered here
I assume I'm using the fgets() wrong. I'm tring to open a PHP file and then try to match a line in that file with a variable I create. If the line does match then I want to write/insert PHP code to the file right below that line. Example:
function remove_admin(){
$findThis = '<tbody id="users" class="list:user user-list">';
$handle = #fopen("../../fns-control/users.php", "r"); // Open file form read.
if ($handle) {
while (!feof($handle)) // Loop til end of file.
{
$buffer = fgets($handle, 479); // Read a line.
if ($buffer == '<tbody id="users" class="list:user user-list">') // Check for string.
{
Now I want to write PHP code to the file, starting on line 480. How can I do that?
Useful information may be: IIS 6 and PHP 5.2.
Try this:
<?php
function remove_admin(){
$path = "../../fns-control/users.php";
$findThis = '<tbody id="users" class="list:user user-list">';
$phpCode = '<?php echo \'hello world\'; ?>';
#Import file to string
$f = file_get_contents($path);
#Add in the PHP code
$newfile = str_replace($findThis, $findThis . $phpCode, $f);
#Overwrite the existing file
$x = fopen($path, 'w');
fwrite($x, $newfile);
fclose($x);
}