Notes

<?php
// http://wallot/test/maj.php


// start with PHP: result always "ANSI" or "UTF-8"
// one step further on Java side: check byte order marks of utf-8 and utf-16 le/be
// put count in a variable before it enters the loop
//converting string to binary
function strToBin($input){
if (!is_string($input))
return false;
$value = unpack('H*', $input);
return base_convert($value[1], 16, 2);
}

//checkFileEncoding function checks the encoding of the file
//@params : $filename: the name or link to the file
// $limit: provide a number to limit the matches of Umlauts .. by default : 2
function checkFileEncoding($filename,$limit = 2){

echo "Checking encoding for file : ",realpath($filename),"<br>";
//getting the file
$file = fopen($filename,'rb');
// creating array to hold binary values of the imported file
$result = array();
//byteArray Array holds binary values of Ä,ä,Ü,ü,Ö,ö,ß
$byteArray = array(
"11000011 10000100",// Ä
"11000011 10100100",// ä
"11000011 10011100",// Ü
"11000011 10111100",// ü
"11000011 10010110",// Ö
"11000011 10110110",// ö
"11000011 10011111" // ß
);

//lcount{lines count} limited to 100 lines only
$lcount = 0;
while($line = fgets($file)){
$line = trim(preg_replace('/s+/', ' ', $line));
if(empty($line))
continue;
$lcount++;
if($lcount <= 100)
for($i=0;$i<strlen($line);$i++){
$result[] = strToBin($line[$i]);
}
}
echo "<br>- line count : {$lcount}";
//$match counts how much umlauts in the file
$match = 0;
//define compinter array holds two bytes in one string in the array separated with space
$combiner = array();
$resultCount = count($result);
//comparing two arrays $byteArray and $result
for($i =0;$i<$resultCount; ){
//all of the umlauts binarys and other symbols start with 11
if($result[$i] != 11000011){
$i++;
continue;
} else {
//combining 2 cells of the array $result to match UTF-8 binary table
$combiner[] = $result[$i] ." ". $result[$i+1];
$i = $i+2;
}

}
foreach($combiner as $cvalue){
foreach($byteArray as $covalue){
if($cvalue == $covalue)
++$match;
}
}

//print_r($combiner);
//echo '<br><pre>',print_r($compiner),'</pre>';
echo $match > 0 ? "<br>- Umlaut match : {$match}" : "<br>- Umlaut match : no match found!";
if($match >= $limit)
echo "<br>- Encoding type of the file is "UTF-8"<br><br><hr>";
else echo "<br>- Encoding type of the file is "ANSI"<br><br><hr>";

//close file read stream
fclose($file);
}
checkFileEncoding("germancharansi.txt");
checkFileEncoding("germancharutf8.txt");
checkFileEncoding("englishchar.txt");