Sample code for 30+ languages & platforms
PHP Extension

Unicode Escape

Demonstrates options for unicode escaping non-us-ascii chars and emojis.

Chilkat PHP Extension Downloads

PHP Extension
<?php

include("chilkat.php");

$success = false;

$sb = new CkStringBuilder();
$success = $sb->LoadFile('qa_data/txt/utf16_emojis_accented_jap.txt','utf-16');
if ($success == false) {
    print $sb->lastErrorText() . "\n";
    exit;
}

$original = $sb->getAsString();

// The above file contains the following text, which includes some emoji's,
// Japanese chars, and accented chars.

// 🧠
// 🔐
// ✅
// ⚠️
// ❌
// ✓
// 中
// é xyz à
// abc 私 は ん ghi

$crypt = new CkCrypt2();

// Charset is not used for unicode escaping.  Set it to "utf-8", but it means nothing.
$charsetNotUsed = 'utf-8';

// Indicate the desired format/style of Unicode escaping.
// Choose JSON-style (JavaScript-style) Unicode escape sequences by using "unicodeescape"
$encoding = 'unicodeescape';

$escaped = $crypt->encodeString($original,$charsetNotUsed,$encoding);
print $escaped . "\n";

// Output:
// \ud83e\udde0
// \ud83d\udd10
// \u2705
// \u26a0\ufe0f
// \u274c
// \u2713
// \u4e2d
// \u00e9 xyz \u00e0
// abc \u79c1 \u306f \u3093 ghi

// Revert back to the unescaped chars:
$unescaped = $crypt->decodeString($escaped,$charsetNotUsed,$encoding);
print $unescaped . "\n";

// -----------------------------------------------------------------------------------------
// Do the same, but use uppercase letters (A-F) in the hex values.
$encoding = 'unicodeescape-upper';
$escaped = $crypt->encodeString($original,$charsetNotUsed,$encoding);
print $escaped . "\n";

// Output:
// \uD83E\uDDE0
// \uD83D\uDD10
// \u2705
// \u26A0\uFE0F
// \u274C
// \u2713
// \u4E2D
// \u00E9 xyz \u00E0
// abc \u79C1 \u306F \u3093 ghi

// Revert back to the unescaped chars:
$unescaped = $crypt->decodeString($escaped,$charsetNotUsed,$encoding);
print $unescaped . "\n";

// -----------------------------------------------------------------------------------------
//  ECMAScript (JavaScript) “code point escape” syntax

$encoding = 'unicodeescape-curly';
$escaped = $crypt->encodeString($original,$charsetNotUsed,$encoding);
print $escaped . "\n";

// Output:
// \u{d83e}\u{dde0}
// \u{d83d}\u{dd10}
// \u{2705}
// \u{26a0}\u{fe0f}
// \u{274c}
// \u{2713}
// \u{4e2d}
// \u{00e9} xyz \u{00e0}
// abc \u{79c1} \u{306f} \u{3093} ghi

// Revert back to the unescaped chars:
$unescaped = $crypt->decodeString($escaped,$charsetNotUsed,$encoding);
print $unescaped . "\n";

// -----------------------------------------------------------------------------------------
// Do the same, but use uppercase letters (A-F) in the hex values.
$encoding = 'unicodeescape-curly-upper';
$escaped = $crypt->encodeString($original,$charsetNotUsed,$encoding);
print $escaped . "\n";

// Output:
// \u{D83E}\u{DDE0}
// \u{D83D}\u{DD10}
// \u{2705}
// \u{26A0}\u{FE0F}
// \u{274C}
// \u{2713}
// \u{4E2D}
// \u{00E9} xyz \u{00E0}
// abc \u{79C1} \u{306F} \u{3093} ghi

// Revert back to the unescaped chars:
$unescaped = $crypt->decodeString($escaped,$charsetNotUsed,$encoding);
print $unescaped . "\n";

// -----------------------------------------------------------------------------------------
// Unicode code point notation or U+ notation

$encoding = 'unicodeescape-plus';
$escaped = $crypt->encodeString($original,$charsetNotUsed,$encoding);
print $escaped . "\n";

// Output:
// u+1f9e0
// u+1f510
// u+2705
// u+26a0u+fe0f
// u+274c
// u+2713
// u+4e2d
// u+00e9 xyz u+00e0
// abc u+79c1 u+306f u+3093 ghi

// Chilkat cannot unescape the Unicode code point notation or U+ notation.
// For this style, Chilkat only goes in one direction, which is to escape.

// To emit uppercase hex, specify unicodeescape-plus-upper
$encoding = 'unicodeescape-plus-upper';
// ...
// ...

// -----------------------------------------------------------------------------------------
// HTML hexadecimal character reference

$encoding = 'unicodeescape-htmlhex';
$escaped = $crypt->encodeString($original,$charsetNotUsed,$encoding);
print $escaped . "\n";

// Output:
// &#x1f9e0;
// &#x1f510;
// &#x2705;
// &#x26a0;&#xfe0f;
// &#x274c;
// &#x2713;
// &#x4e2d;
// &#xe9; xyz &#xe0;
// abc &#x79c1; &#x306f; &#x3093; ghi

// Revert back to the unescaped chars:
$unescaped = $crypt->decodeString($escaped,$charsetNotUsed,$encoding);
print $unescaped . "\n";

// -----------------------------------------------------------------------------------------
// HTML decimal character reference

$encoding = 'unicodeescape-htmldec';
$escaped = $crypt->encodeString($original,$charsetNotUsed,$encoding);
print $escaped . "\n";

// Output:
// &#129504;
// &#128272;
// &#9989;
// &#9888;&#65039;
// &#10060;
// &#10003;
// &#20013;
// &#233; xyz &#224;
// abc &#31169; &#12399; &#12435; ghi

// Revert back to the unescaped chars:
$unescaped = $crypt->decodeString($escaped,$charsetNotUsed,$encoding);
print $unescaped . "\n";

// -----------------------------------------------------------------------------------------
// Hex in Angle Brackets

$encoding = 'unicodeescape-angle';
$escaped = $crypt->encodeString($original,$charsetNotUsed,$encoding);
print $escaped . "\n";

// Output:
// <1f9e0>
// <1f510>
// <2705>
// <26a0><fe0f>
// <274c>
// <2713>
// <4e2d>
// <e9> xyz <e0>
// abc <79c1> <306f> <3093> ghi

// Chilkat cannot unescape the angle bracket notation.
// For this style, Chilkat only goes in one direction, which is to escape.

?>