[SOLVED] Can you read individual bytes from a flat file?

[Meissa]

This is probably really stupid...  maybe I'm wording the question wrong in google

 

Example:

I have a flatfile that is 4 bytes long:  1234

 

I want to assign four different variables:

 

$a = flatfile(byte1)  (I want it to equal "1")

$b = flatfile(byte2)  (I want it to equal "2")

$c = flatfile(byte3)  (so forth, so on...)

$d = flatfile(byte4)

 

I can't figure out the syntax...  is there a way to do this, or is this really too simple to have ever been practical?

 

 

Meissa =/

[gazever]

I'm a complete newbie but this works

 

<?php
$data = '1234';

$a = $data[0];
$b = $data[1];
$c = $data[2];
$d = $data[3];

echo $a."<br>";
echo $b."<br>";
echo $c."<br>";
echo $d."<br>";

?>

 

outputs:-

1
2
3
4

 

 

Gaz

[Meissa]

Wow... I tried that earlier, but didn't have any luck...  maybe I missed something, I'll go back and try again...  Thanks

[boo_lolly]

to read a flat file one byte at a time...

<?php
        /*open file for reading*/
        $fp = fopen('your/directory/file.txt', 'r');

        /*while still reading the file*/
        while(!feof($fp)){
                $character = fgets($fp, 2);
                echo $character ."<br />\n";
        }
?>

 

your situation may call for this, but i wouldn't recommend assigning a new variable for every byte in your flat file. if i were you, i'd store them all into an array.

 

<?php
        /*set array*/
        $array = array();

        /*open file for reading*/
        $fp = fopen('your/directory/file.txt', 'r');

        /*while still reading the file*/
        while(!feof($fp)){
                $array[] = fgets($fp, 2);
        }

        print_r($array);
?>

 

 

[Meissa]

Here's what I'm trying to do.. sorry if I don't write this properly:

 

 

<?php

          /*My homemade counter*/

          $countertxt = "counter.txt";                         
          $fr = fopen($countertxt, 'r');
          $count = fread($fr, filesize($countertxt));       //reads the current value of the flat file
          $count = $count + 1;                             //increments the value by 1
          $fo = fopen($countertxt, 'w');                       
          fwrite($fo, $count);                             //writes the new value to the flat file
          echo $count;                                     //everything at this point works fine

          /*Here's where I'm running into trouble*/
         
          /*I want to make the page display a .GIF file according to the number that is stored in the flat file*/
          $a = $count[0];
          $b = $count[1];
          $c = $count[2];
          $d = $count[3];

          echo "<img src='$a.GIF'>";
          echo "<img src='$b.GIF'>";
          echo "<img src='$c.GIF'>";
          echo "<img src='$d.GIF'>";

?>

 

 

I'm unable to read the variable $count one byte at a time

 

However, if I were to assign the value like this:

 

$count = '1234';

 

It works properly... for some reason it won't treat $count like a variable with 4 numbers... probably because $count is associated with opening files... 

 

Any thoughts?

 

 

 

 

 

 

[gazever]

Try This,

 

Again I am a newbie, sure someone has a better way, but seems you need to convert it from a number to a string.

 

<?php

          /*My homemade counter*/

          $countertxt = "counter.txt";                         
          $fr = fopen($countertxt, 'r');
          $count = fread($fr, filesize($countertxt));       //reads the current value of the flat file
          $count = $count + 1;                             //increments the value by 1
          $fo = fopen($countertxt, 'w');                       
          fwrite($fo, $count);                             //writes the new value to the flat file
          echo $count;                                     //everything at this point works fine
	  
		$data = strval($count);   /// need to convert the number to a string to use the method below

          /*Here's where I'm running into trouble*/
         
          /*I want to make the page display a .GIF file according to the number that is stored in the flat file*/
          $a = $data[0];
          $b = $data[1];
          $c = $data[2];
          $d = $data[3];

          echo "<img src='$a.GIF'>";
          echo "<img src='$b.GIF'>";
          echo "<img src='$c.GIF'>";
          echo "<img src='$d.GIF'>";

?>

 

This works

 

Gaz

[Meissa]

Dude, you absolutely rock!!  Thanks a lot.

[boo_lolly]

i'm sorry i misunderstood the issue. try this:

<?php
        /*set array*/
        $array = array();

        /*open file for reading*/
        $fp = fopen('your/directory/file.txt', 'r');

        /*store each byte into an index in the array*/
        while(!feof($fp)){
                $array[] = fgets($fp, 2);
        }

        /*print each index in the array as an image name*/
        foreach($array as $img){
                echo "<img src=\"{$img}.GIF\"><br />\n";
        }
?>

[gazever]

Melissa, thanks

 

Newer code here

 

<?php

          /*My homemade counter*/

          $countertxt = "counter.txt";                         
          $fr = fopen($countertxt, 'r');
          $count = fread($fr, filesize($countertxt));       //reads the current value of the flat file
          $count = $count + 1;                             //increments the value by 1
          $fo = fopen($countertxt, 'w');                       
          fwrite($fo, $count);                             //writes the new value to the flat file
          echo $count;                                     //everything at this point works fine
	  
	  
	  if ($count < 10){                   //
	  $count = "0".$count;
	  }
	   if ($count < 100){
	  $count = "0".$count;            //code here added to add prevailing zeros before number reaches 1000, to 
	  }                                // display 0004, 0014, 0114 etc.
	   if ($count < 1000){
	  $count = "0".$count;
	  }                                //

		$data = strval($count);   /// need to convert the number to a string to use the method below

          /*Here's where I'm running into trouble*/
         

          /*I want to make the page display a .GIF file according to the number that is stored in the flat file*/
          $a = $data[0];
          $b = $data[1];
          $c = $data[2];
          $d = $data[3];

          echo "<img src='$a.GIF'>";
          echo "<img src='$b.GIF'>";
          echo "<img src='$c.GIF'>";
          echo "<img src='$d.GIF'>";

?>

 

Problem when display a count 0f 0014, etc, would display as 14-- as there the first two characters hope you understand what im on about.

 

Gaz