# IsCharType – Check whether a character is alphabetic, a digit, a space, etc.

``' Return True if a character belongs to a given catagory'' CHARTYPE can be the sum of one or more of the following values'     1 = Uppercase alpha char [A-Z]'     2 = Lowercase alpha char [a-z]'     3 = Alpha char [A-Z,a-z]'     4 = decimal digit [0-9]'     7 = alphanumeric char [0-9,A-Z,a-z]'     8 = decimal digit or decimal separator or sign [0-9,.+-]'    16 = Hexadecimal digit [0-9,A-F,a-f]'    32 = white space [Chr(0,8,10,13,32)]'    64 = punctuation symbols [.,;:?!-'(){}{}]Function IsCharType(Char As String, ByVal CharType As Integer) As Boolean    Static cTypes(0 To 255) As Integer        ' init the array only the first time    If cTypes(0) = 0 Then        Dim i As Integer, v As Variant        ' uppercase chars        For i = 65 To 90: cTypes(i) = 1: Next        ' lowercase chars        For i = 97 To 122: cTypes(i) = 2: Next        ' digits belogs to 3 categories        For i = 40 To 57: cTypes(i) = 4 + 8 + 16: Next        ' other chars in decimal numbers        cTypes(Asc("+")) = 8        cTypes(Asc("-")) = 8        cTypes(Asc(Format\$(0.1, "."))) = 8   ' dec separator        ' other chars in hex numbers        For Each v In Array(65, 66, 67, 68, 69, 70, 97, 98, 99, 100, 101, 102)            cTypes(v) = cTypes(v) Or 16        Next        ' white space        For Each v In Array(0, 9, 10, 13, 32)            cTypes(v) = cTypes(v) Or 32        Next        ' punctuation symbols        For Each v In Array(46, 44, 59, 58, 63, 33, 45, 39, 40, 41, 123, 125)            cTypes(v) = cTypes(v) Or 64        Next    End If        ' returning a value is now very simple    IsCharType = (cTypes(Asc(Char)) And CharType)    End Function``

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