(PowerBuilder) Punycode Encoding / Decoding

Punycode is an encoding standard for representing Unicode characters using only the 7bit us-ascii characters that are permitted in network host names. Punycode is used for internationalized domain names -- i.e. IDN or IDNA (Internationalizing Domain Names in Applications).

Punycode is defined in RFC 3492. Converting to/from punycode does not include the "xn--" prefix. The "xn--" prefix is to signify that punycode follows. For example, the string " café.com" is converted to "caf-dma.com" in punycode. The punycode domain name is "xn--caf-dma.com".

Converting an email address to punycode would be as follows. Suppose the email address is "coffee@café.com". The punycode representation is "coffee@xn--caf-dma.com". The RFC 3492 punycode representation of "café.com" is simply "caf-dma.com", but the punycode domain name is "xn--caf-dma.com".

The "xn--" is a constant. It is the same regardless of the domain. For example, the punycode URL representation of "mañana.com" is "xn--maana-pta.com".

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

integer li_rc
integer li_Success
oleobject loo_Sb


loo_Sb = create oleobject
// Use "Chilkat_9_5_0.StringBuilder" for versions of Chilkat < 10.0.0
li_rc = loo_Sb.ConnectToNewObject("Chilkat.StringBuilder")
if li_rc < 0 then
    destroy loo_Sb
    MessageBox("Error","Connecting to COM object failed")
    return
end if

// Load the string "café" from a utf-8 text file.
li_Success = loo_Sb.LoadFile("qa_data/txt/cafe.txt","utf-8")

loo_Sb.PunyEncode()
Write-Debug loo_Sb.GetAsString()

loo_Sb.PunyDecode()
Write-Debug loo_Sb.GetAsString()

// The output is:
// 
// caf-dma
// café


destroy loo_Sb