Convert Hindi text to Escaped Unicode character with php - php

Question

I want to convert hindi / Devanagari text for example "आए थे पर्यटक, खुद ही बह ग" into Unicode escaped characters like "\u0906\u090f \u0925\u0947 \u092a\u0930\u094d\u092f\u091f\u0915, \u0916\u0941\u0926 \u0939\u0940 \u092c\u0939 \u0917".
I am developing a hindi website and i have seen most of sites are using Escaped Unicode sequence inside their meta tags and schema.org.
So i decided to give it a try.
i can see Hindi AKA Devanagari letters with their Escaped Unicode sequence at http://www.endmemo.com/unicode/devanagari.php
and i have also seen a tool which works the same https://www.mobilefish.com/services/unicode_escape_sequence_converter/unicode_escape_sequence_converter.php
but i cannot find any way to convert these Devanagari letters into Escaped Unicode sequence via php.
I have tried few things but nothing is working and i am not getting much help from google because all articles / forums are talking to decoding unicode escape sequence to unicode but none of them is taking about encoding..
header( 'Content-Type: text/html; charset=utf-8' );
function encode2($str) {
$str = mb_convert_encoding($str , 'UTF-32', 'UTF-8');
$t = unpack("N*", $str);
$t = array_map(function($n) { return "&#$n;"; }, $t);
return implode("", $t);
}
$message = "आए थे पर्यटक, खुद ही बह गए";
$message_convert = encode2($message);
echo $message_convert;
echo "fdfdfdfdfdfdfd<br/>";
echo mb_convert_encoding($message, "HTML-ENTITIES", "auto");
I want this "आए थे पर्यटक, खुद ही बह ग" to "\u0906\u090f \u0925\u0947 \u092a\u0930\u094d\u092f\u091f\u0915, \u0916\u0941\u0926 \u0939\u0940 \u092c\u0939 \u0917"
Please help!

Answer 1

as suggest by #paskl i tried:
$message = "आए थे पर्यटक, खुद ही बह गए";
$unicode = json_encode($message)
echo $unicode;
And i got ""\u0906\u090f \u0925\u0947 \u092a\u0930\u094d\u092f\u091f\u0915, \u0916\u0941\u0926 \u0939\u0940 \u092c\u0939 \u0917\u090f""
I hope it will help others who want to convert devanagari/hindi letters into Escaped Unicode sequence with php on their website.
Thanks to #paskl

Answer 2

Unless you're looking to transmit this data as JSON I wouldn't really recommend using json_encode() as it will wrap your output in literal double quotes that you'd need to strip back off. However there's not an easy way to encode unicode escapes in PHP in a way that is memory-efficient.
That said, here is the not-easy code:
// PHP < 7.2
// https://github.com/symfony/polyfill-mbstring/blob/master/Mbstring.php#L708-L730
if( ! function_exists("mb_ord") ) {
function mb_ord($s) {
if (1 === \strlen($s)) {
return \ord($s);
}
$code = ($s = unpack('C*', substr($s, 0, 4))) ? $s[1] : 0;
if (0xF0 <= $code) {
return (($code - 0xF0) << 18) + (($s[2] - 0x80) << 12) + (($s[3] - 0x80) << 6) + $s[4] - 0x80;
}
if (0xE0 <= $code) {
return (($code - 0xE0) << 12) + (($s[2] - 0x80) << 6) + $s[3] - 0x80;
}
if (0xC0 <= $code) {
return (($code - 0xC0) << 6) + $s[2] - 0x80;
}
return $code;
}
}
function ord2seqlen($ord) {
if($ord < 128){
return 1;
} else if($ord < 224) {
return 2;
} else if($ord < 240) {
return 3;
} else if($ord < 248) {
return 4;
} else {
throw new \Exception("No support for 5 or 6 byte sequences.");
}
}
function utf8_seq_iter($input) {
for($i=0,$c=strlen($input); $i<$c; ) {
$bytes = ord2seqlen(ord($input[$i]));
yield substr($input, $i, $bytes);
$i += $bytes;
}
}
function escape_codepoint($codepoint, $skip_low=true) {
$ord = mb_ord($codepoint);
if( $skip_low && $ord < 128 ) {
return $codepoint;
} else {
return sprintf("\\u%04x", $ord);
}
}
$input = "आए थे पर्यटक, खुद ही बह गए";
$output = '';
foreach( utf8_seq_iter($input) as $codepoint ) {
$output .= escape_codepoint($codepoint);
}
var_dump($output);
Output:
string(121) "\u0906\u090f \u0925\u0947 \u092a\u0930\u094d\u092f\u091f\u0915, \u0916\u0941\u0926 \u0939\u0940 \u092c\u0939 \u0917\u090f"
Edit: I've turned this into a small composer package available here:
https://packagist.org/packages/wrossmann/utf8_escape