Visual FoxPro Requires Chilkat v11.1.0+

Unicode Escape and Unescape Text in StringBuilder

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

LOCAL lnSuccess
LOCAL loSbOriginal
LOCAL loSb
LOCAL lcCharsetNotUsed
LOCAL lcEncoding

lnSuccess = 0

loSbOriginal = CreateObject('Chilkat.StringBuilder')
lnSuccess = loSbOriginal.LoadFile("qa_data/txt/utf16_emojis_accented_jap.txt","utf-16")
IF (lnSuccess = 0) THEN
    ? loSbOriginal.LastErrorText
    RELEASE loSbOriginal
    CANCEL
ENDIF

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

loSb = CreateObject('Chilkat.StringBuilder')
loSb.AppendSb(loSbOriginal)

*  Charset is not used for unicode escaping.  Set it to "utf-8", but it means nothing.
lcCharsetNotUsed = "utf-8"

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

loSb.Encode(lcEncoding,lcCharsetNotUsed)
? loSb.GetAsString()

*  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:
loSb.Decode(lcEncoding,lcCharsetNotUsed)
? loSb.GetAsString()

*  -----------------------------------------------------------------------------------------
*  Do the same, but use uppercase letters (A-F) in the hex values.
lcEncoding = "unicodeescape-upper"
loSb.Encode(lcEncoding,lcCharsetNotUsed)
? loSb.GetAsString()

*  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:
loSb.Decode(lcEncoding,lcCharsetNotUsed)
? loSb.GetAsString()

*  -----------------------------------------------------------------------------------------
*   ECMAScript (JavaScript) �code point escape� syntax

lcEncoding = "unicodeescape-curly"
loSb.Encode(lcEncoding,lcCharsetNotUsed)
? loSb.GetAsString()

*  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:
loSb.Decode(lcEncoding,lcCharsetNotUsed)
? loSb.GetAsString()

*  -----------------------------------------------------------------------------------------
*  Do the same, but use uppercase letters (A-F) in the hex values.
lcEncoding = "unicodeescape-curly-upper"
loSb.Encode(lcEncoding,lcCharsetNotUsed)
? loSb.GetAsString()

*  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:
loSb.Decode(lcEncoding,lcCharsetNotUsed)
? loSb.GetAsString()

*  -----------------------------------------------------------------------------------------
*  HTML hexadecimal character reference

lcEncoding = "unicodeescape-htmlhex"
loSb.Encode(lcEncoding,lcCharsetNotUsed)
? loSb.GetAsString()

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

*  Revert back to the unescaped chars:
loSb.Decode(lcEncoding,lcCharsetNotUsed)
? loSb.GetAsString()

*  -----------------------------------------------------------------------------------------
*  HTML decimal character reference

lcEncoding = "unicodeescape-htmldec"
loSb.Encode(lcEncoding,lcCharsetNotUsed)
? loSb.GetAsString()

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

*  Revert back to the unescaped chars:
loSb.Decode(lcEncoding,lcCharsetNotUsed)
? loSb.GetAsString()

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

lcEncoding = "unicodeescape-plus"
loSb.Encode(lcEncoding,lcCharsetNotUsed)
? loSb.GetAsString()

*  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
lcEncoding = "unicodeescape-plus-upper"
*  ...
*  ...

loSb.Clear()
loSb.AppendSb(loSbOriginal)

*  -----------------------------------------------------------------------------------------
*  Hex in Angle Brackets

lcEncoding = "unicodeescape-angle"
loSb.Encode(lcEncoding,lcCharsetNotUsed)
? loSb.GetAsString()

*  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.

loSb.Clear()
loSb.AppendSb(loSbOriginal)

RELEASE loSbOriginal
RELEASE loSb