PHP Read File as an Array of Bytes

PHP read file as an array of bytes

I believe the code you are looking for is:

$byteArray = unpack("N*",file_get_contents($filename));

UPDATE: Working code supplied by OP

$filename = "myFile.sav"; 
$handle = fopen($filename, "rb"); 
$fsize = filesize($filename); 
$contents = fread($handle, $fsize); 
$byteArray = unpack("N*",$contents); 
print_r($byteArray); 
for($n = 0; $n < 16; $n++)
{ 
    echo $byteArray [$n].'<br/>'; 
}

how to convert the file content to byte array with php

PHP doesn't have a "byte array" data type. What it has is a string type, which is a byte array for all intents and purposes. To read the binary content of a file into a variable which is as close to a byte array as you'll ever get in PHP, do:

$content = file_get_contents($_FILES['my_file']['tmp_name']);

Yup, that's it. Nothing more to do.

I'm not particular familiar with the sqlsrv API, but perusing its documentation it appears that you can (need to?) set a flag this way to flag the data as being binary:

sqlsrv_query($conn, 'INSERT INTO files (file_data) VALUES (?)', array(
    array($content, SQLSRV_PARAM_IN, SQLSRV_PHPTYPE_STRING, SQLSRV_SQLTYPE_BINARY)
));

Get part of a file by byte number in php

Use fseek() and fread()

$fp = fopen('somefile.txt', 'r');

// move to the 7th byte
fseek($fp, 7);

$data = fread($fp, 8);   // read 8 bytes from byte 7

fclose($fp);

read single byte from PHP uploaded file

Thank you very much for the "ultimate goal" -- it will help us make sure that you don't do something silly by accident.

Encryption is a very complex topic. You should not write your own encryption routine. Use a complete, pre-built solution.

Mcrypt is PHP's best encryption extension. Mcrypt supports multiple common ciphers including AES ("Rijndael"). Encryption is pretty darn easy -- use "CBC" mode for your file.

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The Vigenère cipher is a 460-ish year old substitution cipher based on a simple lookup table.

This explains the whole one-character-at-a-time thing.

While you can read the whole file one byte at a time, you might find it more convenient to work with a string. You can read the entire file into a variable (through file_get_contents or whatever), and then use substr or the square bracket substring syntax to read the string one byte at a time. Remember, PHP strings are just simple lists of bytes.

Given $data is the complete data in the file, you can process every byte thusly:

$length = strlen($data);
for($i = 0; $i < $length; $i++) {
    $byte = $data[$i];
// Or
    $byte = substr($data, $i, 1);
// Process the byte here.
}

This is only practical for small files (smaller than a few megabytes), as it requires loading the whole file into memory.

I want to print out the acscii (HEX) code for this byte

You can get the decimal value using ord, then convert that to a hexadecimal string using dechex:

$hex_value = dechex(ord($byte));

Post-substitution, you can reverse it -- use hexdec to go from hex to decimal, then chr to go from decimal to byte:

$converted_byte = chr(hexdec($ciphered_hex));

PHP Read Byte Range from String or File

You should be able to do this with fseek and fread.

<?php
$byteOffset = 1024;
$readLength = 256;
$fileHandle = fopen('myfile', 'r');
fseek($fileHandle, $byteOffset);
$bytes = fread($fileHandle, $readLength);

how to covert xml file to byte array in php

A variation of this question has been answered before.
See the approved answer here:
String to byte array in php

For completeness, I'll put this in the context of your question:

$xmlStr = file_get_contents('sample.xml'); // read file to string
$byte_array = unpack('C*', $xmlStr); // convert string to byte array
var_dump($byte_array); // output your resulting byte array

See the PHP documentation for details on unpack: http://php.net/manual/en/function.unpack.php

Edit: I saw in a comment you mentioned this method didn't work. Attached are my results from a small test:

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