C#

Unicode Escape

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

bool success = false;

Chilkat.StringBuilder sb = new Chilkat.StringBuilder();
success = sb.LoadFile("qa_data/txt/utf16_emojis_accented_jap.txt","utf-16");
if (success == false) {
    Debug.WriteLine(sb.LastErrorText);
    return;
}

string 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

Chilkat.Crypt2 crypt = new Chilkat.Crypt2();

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

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

string escaped = crypt.EncodeString(original,charsetNotUsed,encoding);
Debug.WriteLine(escaped);

//  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:
string unescaped = crypt.DecodeString(escaped,charsetNotUsed,encoding);
Debug.WriteLine(unescaped);

//  -----------------------------------------------------------------------------------------
//  Do the same, but use uppercase letters (A-F) in the hex values.
encoding = "unicodeescape-upper";
escaped = crypt.EncodeString(original,charsetNotUsed,encoding);
Debug.WriteLine(escaped);

//  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);
Debug.WriteLine(unescaped);

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

encoding = "unicodeescape-curly";
escaped = crypt.EncodeString(original,charsetNotUsed,encoding);
Debug.WriteLine(escaped);

//  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);
Debug.WriteLine(unescaped);

//  -----------------------------------------------------------------------------------------
//  Do the same, but use uppercase letters (A-F) in the hex values.
encoding = "unicodeescape-curly-upper";
escaped = crypt.EncodeString(original,charsetNotUsed,encoding);
Debug.WriteLine(escaped);

//  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);
Debug.WriteLine(unescaped);

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

encoding = "unicodeescape-plus";
escaped = crypt.EncodeString(original,charsetNotUsed,encoding);
Debug.WriteLine(escaped);

//  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);
Debug.WriteLine(escaped);

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

//  Revert back to the unescaped chars:
unescaped = crypt.DecodeString(escaped,charsetNotUsed,encoding);
Debug.WriteLine(unescaped);

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

encoding = "unicodeescape-htmldec";
escaped = crypt.EncodeString(original,charsetNotUsed,encoding);
Debug.WriteLine(escaped);

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

//  Revert back to the unescaped chars:
unescaped = crypt.DecodeString(escaped,charsetNotUsed,encoding);
Debug.WriteLine(unescaped);

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

encoding = "unicodeescape-angle";
escaped = crypt.EncodeString(original,charsetNotUsed,encoding);
Debug.WriteLine(escaped);

//  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.