Php detection data encoding type

Php detection file encoding type define (UTF32_BIG_ENDIAN_BOM & nbsp;, chr (0x00 ). chr (0x00 ). chr (0xFE ). chr (0xFF); define (UTF32_LITTLE_ENDIAN_BOM, chr (0xFF ). chr (0xFE ). chr (0x00) php detects file encoding types
Define ('utf32 _ BIG_ENDIAN_BOM ', chr (0x00). chr (0x00). chr (0xFE). chr (0xFF ));
Define ('utf32 _ LITTLE_ENDIAN_BOM ', chr (0xFF). chr (0xFE). chr (0x00). chr (0x00 ));
Define ('utf16 _ BIG_ENDIAN_BOM ', chr (0xFE). chr (0xFF ));
Define ('utf16 _ LITTLE_ENDIAN_BOM ', chr (0xFF). chr (0xFE ));
Define ('utf8 _ BOM ', chr (0xEF). chr (0xBB). chr (0xBF ));

Function detect_utf_encoding ($ text ){
$ First2 = substr ($ text, 0, 2 );
$ First3 = substr ($ text, 0, 3 );
$ First4 = substr ($ text, 0, 3 );

If ($ first3 = UTF8_BOM) return 'utf-8 ';
Elseif ($ first4 = UTF32_BIG_ENDIAN_BOM) return 'utf-32BE ';
Elseif ($ first4 = UTF32_LITTLE_ENDIAN_BOM) return 'utf-32le ';
Elseif ($ first2 = UTF16_BIG_ENDIAN_BOM) return 'utf-16BE ';
Elseif ($ first2 = UTF16_LITTLE_ENDIAN_BOM) return 'utf-16le ';
}

Function getFileEncoding ($ str ){
$ Encoding = mb_detect_encoding ($ str );
If (empty ($ encoding )){
$ Encoding = detect_utf_encoding ($ str );
}
Return $ encoding;
}
$ File = 'text1.txt ';
Echo getFileEncoding (file_get_contents ($ file); // output ASCII
Echo '';

$ File = 'text2.txt ';
Echo getFileEncoding (file_get_contents ($ file); // output UTF-8
Echo '';
$ File = 'text3.txt ';
Echo getFileEncoding (file_get_contents ($ file); // output UTF-16LE
Echo '';