I'm just wondering how I can read a text file in php, I'd like to have it display the last 200 entries (their each on a new line) from the text file.
Like
John White
Jane Does
John Does
Someones Name
and so on
Thanks!
Use fopen and fgets, or possibly just file.
There are several methods for reading text from files in PHP.
You could use fgets, fread, etc. Load the file into a dynamic array, then just output the last 200 elements of that array.
file will get the contents of a file and put it into an array. After that, it's like JYelton said, output the last 200 elements.
This outputs last 200 rows. Last row first:
$lines = file("filename.txt");
$top200 = array_slice(array_reverse($lines),0,200);
foreach($top200 as $line)
{
echo $line . "<br />";
}
<?php
$myfile = fopen("file_name.txt", "r") or die("Unable to open file!");
// Output one character until end-of-file
while(!feof($myfile)) {
echo fgetc($myfile);
}
fclose($myfile);
?>
You may use this
Related
I have a flat file, TestFile.txt, that contains about 200 lines. Each item is a separate row. I show a partial of the contents of the TestFile.txt file below. I have PHP code working that reads TestFile.txt exactly as I need. The PHP read code searches the TestFile.txt, locates the line I wish to read, and places the result into an html input box. It parses the text after the = in the line, and only displays the data found after the =. Just as I need. Now I need to change the data in the html input box, and write the change back to TestFile.txt, and only update the text after the =. I show the PHP read code below. I have not a clue how to do what I need. I am a little over a week studying PHP. Any help with writing is much appreciated.
Thanks,
Mitch
Partial TestFile.txt:
RXFrequency=432675000
TXFrequency=432675000
RXOffset=260
TXOffset=120
Network=mnet.hopto.org
Password=9Yg81prqL0363zt
Latitude=34.657783
Longitude=-3.784595
Port=62021
Part of the PHP:
<!DOCTYPE html>
<html>
<body>
<?php
// Place text to look for in string $Search_String.
// The $Search_String will remain hard coded in my production
// code. The users will not be able to select $Search_String.
$Search_String_1 = "RXOff";
// Identify Text File, open File and Read the File.
$MyFile = fopen("TestFile.txt", "r") or die("Unable to open file!");
$found= "False";
// Create the while loop. Test each line with the if statement,
// looking for $Search_String, and place the result into string $line.
// Next, echo string $line which containes the found line in the
// flat text file. It will return the entire line even from a
// partial $Search_String, which is what I want.
/*...*/
// Next, let us build the array.
$lines = [];
while ( $line = fgets( $MyFile ) ) {
if ( str_contains( $line, $Search_String_1 ) ) {
//here you are keeping track of each line matching the criteria.
$lines[] = $line;
// This explode function will split the string contained
// in the $line variable at the =. Text left of the = is
// placed into the $key variable. Text right of the = is
// placed into the $value variable.
[$key, $value] = explode("=", "$line");
// echo $key; // RXOffset;
// echo $value; // 260;
//echo $line;
//echo $Search_String_1;
}
}
?>
<?php foreach($lines as $line): ?>
<?php endforeach;
// Properly close the text file.
fclose($MyFile);
// Get string $value from the explode code above.
?>
<label>RXOffset: <input type="text" id="message" value="<?php echo $value;?>"/></label>
<?php
</body>
<html>
Hope this gives enough information. Feel free to comment questions.
Thanks,
Mitch
This is what appears on the browser when I execute this PHP:
RXOffset: 269
Label Data
My text file sample.txt. I want to exclude the first row from the text file and store the other rows into mysql database.
ID Name EMail
1 Siva xyz#gmail.com
2 vinoth xxx#gmail.com
3 ashwin yyy#gmail.com
Now I want to read this data from the text file except the first row(ID,name,email) and store into the MYsql db.Because already I have created a filed in database with the same name.
I have tried
$handle = #fopen($filename, "r"); //read line one by one
while (!feof($handle)) // Loop till end of file.
{
$buffer = fgets($handle, 4096); // Read a line.
}
print_r($buffer); // It shows all the text.
Please let me know how to do this?
Thanks.
Regards,
Siva R
It's easier if you use file() since it will get all rows in an array instead:
// Get all rows in an array (and tell file not to include the trailing new lines
$rows = file($filename, FILE_IGNORE_NEW_LINES);
// Remove the first element (first row) from the array
array_shift($rows);
// Now do what you want with the rest
foreach ($rows as $lineNumber => $row) {
// do something cool with the row data
}
If you want to get it all as a string again, without the first row, just implode it with a new line as glue:
// The rows still contain the line break, since we only trimmed the copy
$content = implode("\n", $rows);
Note: As #Don'tPanic pointed out in his comment, using file() is simple and easy but not advisable if the original file is large, since it will read the whole thing into memory as an array (and arrays take more memory than strings). He also correctly recommended the FILE_IGNORE_NEW_LINES-flag, just so you know :-)
You can just call fgets once before your while loop to get the header row out of the way.
$firstline = fgets($handle, 4096);
while (!feof($handle)) // Loop till end of file.
{ ...
This question already has answers here:
Need to write at beginning of file with PHP
(10 answers)
Closed 9 years ago.
Hi I want to append a row at the beginning of the file using php.
Lets say for example the file is containing the following contnet:
Hello Stack Overflow, you are really helping me a lot.
And now i Want to add a row on top of the repvious one like this:
www.stackoverflow.com
Hello Stack Overflow, you are really helping me a lot.
This is the code that I am having at the moment in a script.
$fp = fopen($file, 'a+') or die("can't open file");
$theOldData = fread($fp, filesize($file));
fclose($fp);
$fp = fopen($file, 'w+') or die("can't open file");
$toBeWriteToFile = $insertNewRow.$theOldData;
fwrite($fp, $toBeWriteToFile);
fclose($fp);
I want some optimal solution for it, as I am using it in a php script. Here are some solutions i found on here:
Need to write at beginning of file with PHP
which says the following to append at the beginning:
<?php
$file_data = "Stuff you want to add\n";
$file_data .= file_get_contents('database.txt');
file_put_contents('database.txt', $file_data);
?>
And other one here:
Using php, how to insert text without overwriting to the beginning of a text file
says the following:
$old_content = file_get_contents($file);
fwrite($file, $new_content."\n".$old_content);
So my final question is, which is the best method to use (I mean optimal) among all the above methods. Is there any better possibly than above?
Looking for your thoughts on this!!!.
function file_prepend ($string, $filename) {
$fileContent = file_get_contents ($filename);
file_put_contents ($filename, $string . "\n" . $fileContent);
}
usage :
file_prepend("couldn't connect to the database", 'database.logs');
My personal preference when writing to a file is to use file_put_contents
From the manual:
This function is identical to calling fopen(), fwrite() and fclose()
successively to write data to a file.
Because the function automatically handles those three functions for me I do not have to remember to close the resource after I'm done with it.
There is no really efficient way to write before the first line in a file. Both solutions mentioned in your questions create a new file from copying everything from the old one then write new data (and there is no much difference between the two methods).
If you are really after efficiency, ie avoiding the whole copy of the existing file, and you need to have the last inserted line being the first in the file, it all depends how you plan on using the file after it is created.
three files
Per you comment, you could create three files header, content and footer and output each of them in sequence ; that would avoid the copy even if header is created after content.
work reverse in one file
This method puts the file in memory (array).
Since you know you create the content before the header, always write lines in reverse order, footer, content, then header:
function write_reverse($lines, $file) { // $lines is an array
for($i=count($lines)-1 ; $i>=0 ; $i--) fwrite($file, $lines[$i]);
}
then you call write_reverse() first with footer, then content and finally header. Each time you want to add something at the beginning of the file, just write at the end...
Then to read the file for output
$lines = array();
while (($line = fgets($file)) !== false) $lines[] = $line;
// then print from last one
for ($i=count($lines)-1 ; $i>=0 ; $i--) echo $lines[$i];
Then there is another consideration: could you avoid using files at all - eg via PHP APC
You mean prepending. I suggest you read the line and replace it with next line without losing data.
<?php
$dataToBeAdded = "www.stackoverflow.com";
$file = "database.txt";
$handle = fopen($file, "r+");
$final_length = filesize($file) + strlen($dataToBeAdded );
$existingData = fread($handle, strlen($dataToBeAdded ));
rewind($handle);
$i = 1;
while (ftell($handle) < $final_length)
{
fwrite($handle, $dataToBeAdded );
$dataToBeAdded = $existingData ;
$existingData = fread($handle, strlen($dataToBeAdded ));
fseek($handle, $i * strlen($dataToBeAdded ));
$i++;
}
?>
I'm experimenting with fopen for the first time and was wondering if it was possible to search for a particular section within a file before adding or replacing that content with data?
Ideally, I'd like to:
Use fopen to get the file
Search for a comment called <!-- test -->
Replace that comment with new data.
This possible? (for the record - Appending data to the end of the file or adding new data to a specific line number would not work for what I'm working on as the file is constantly changing).
Thanks!
<?php
// make sure radio is set
if( isset($_POST['enableSocialIcons']) )
{
// Open file for read and string modification
$file = "/test";
$fh = fopen($file, 'r+');
$contents = fread($fh, filesize($file));
$new_contents = str_replace("hello world", "hello", $contents);
fclose($fh);
// Open file to write
$fh = fopen($file, 'r+');
fwrite($fh, $new_contents);
fclose($fh);
}
?>
From: http://www.php.net/manual/en/function.fopen.php#81325
EDIT: To see what exactly is getting sent by your form do this at the top of the PHP file you're posting to:
<?php
echo '<pre>';
print_r($_POST);
echo '</pre>';
exit;
?>
If you read the entire file in then use something str_replace to make the change, you should be able to get what you want.
suppose I do have a text file with these lines
name: Mathew
Age : 32
Country : USA
Location : California
bla bla bla....
What I want is I want a php code which can read this file and display result to a webpage.
Use this code (untested):
$fp = fopen('filename.php');
while (!eof($fp)) {
$line = fgets($fp);
// Add code to display the values how you want
echo $line."<br>";
}
fclose($fp);
That will loop through the file line by line. Each line will be assigned to the $line variable, and then you can manipulate and display the values how you would like.
file() function reads a file into an array where one element represents a string in the file
Display the actual text or remove the name:, etc?
Use the file() function (tutorial?) to read the file in and then echo out / process each line.