Android Code Snippet [B4X] Unescape Unicode

Unescapes characters encoded with the \uXXXX notion.

Example:

Log(UnescapeUnicode("this is a test \u2764\ufe0f\u2764\ufe0f\u2764\ufe0f1234!!!"))

Sub UnescapeUnicode(s As String) As String
    Dim sb As StringBuilder
    sb.Initialize
    Dim lastMatchEnd As Int = 0
    Dim m As Matcher = Regex.Matcher("\\u+([0-9A-Fa-f]{4})", s)
    Do While m.Find
        Dim currentStart As Int = m.GetStart(0)
        sb.Append(s.SubString2(lastMatchEnd, currentStart))
        sb.Append(Chr(Bit.ParseInt(m.Group(1), 16)))
        lastMatchEnd = m.GetEnd(0)
    Loop
    If lastMatchEnd < s.Length Then sb.Append(s.SubString(lastMatchEnd))
    Return sb.ToString
End Sub