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ctype<char> Class

The class is an explicit specialization of class template ctype\<CharType> to type char, describing an object that can serve as a locale facet to characterize various properties of a character of type char.

Syntax

template <>
class ctype<char>
: public ctype_base
{
public:
    typedef char _Elem;
    typedef _Elem char_type;
    bool is(
    mask _Maskval,
    _Elem _Ch) const;

    const _Elem* is(
    const _Elem* first,
    const _Elem* last,
    mask* dest) const;

    const _Elem* scan_is(
    mask _Maskval,
    const _Elem* first,
    const _Elem* last) const;

    const _Elem* scan_not(
    mask _Maskval,
    const _Elem* first,
    const _Elem* last) const;

    _Elem tolower(
    _Elem _Ch) const;

    const _Elem* tolower(
    _Elem* first,
    const _Elem* last) const;

    _Elem toupper(
    _Elem _Ch) const;

    const _Elem* toupper(
    _Elem* first,
    const _Elem* last) const;

    _Elem widen(
    char _Byte) const;

    const _Elem* widen(
    const char* first,
    const char* last,
    _Elem* dest) const;

    const _Elem* _Widen_s(
    const char* first,
    const char* last,
    _Elem* dest,
    size_t dest_size) const;

    _Elem narrow(
    _Elem _Ch,
    char _Dflt = '\0') const;

    const _Elem* narrow(
    const _Elem* first,
    const _Elem* last,
    char _Dflt,
    char* dest) const;

    const _Elem* _Narrow_s(
    const _Elem* first,
    const _Elem* last,
    char _Dflt,
    char* dest,
    size_t dest_size) const;

    static locale::id& id;
    explicit ctype(
    const mask* _Table = 0,
    bool _Deletetable = false,
    size_t _Refs = 0);

protected:
    virtual ~ctype();
//other protected members
};

Remarks

The explicit specialization differs from the class template in several ways:

  • An object of class ctype<char> stores a pointer to the first element of a ctype mask table, an array of UCHAR_MAX + 1 elements of type ctype_base::mask. It also stores a Boolean object that indicates whether the array should be deleted (using operator delete[]) when the ctype< Elem> object is destroyed.

  • Its sole public constructor lets you specify tab, the ctype mask table, and del, the Boolean object that is true if the array should be deleted when the ctype<char> object is destroyed, as well as the reference-count parameter refs.

  • The protected member function table returns the stored ctype mask table.

  • The static member object table_size specifies the minimum number of elements in a ctype mask table.

  • The protected static member function classic_table( returns the ctype mask table appropriate to the "C" locale.

  • There are no protected virtual member functions do_is, do_scan_is, or do_scan_not. The corresponding public member functions perform the equivalent operations themselves.

The member functions do_narrow and do_widen copy elements unaltered.

Requirements

Header: <locale>

Namespace: std

See also

facet Class
ctype_base Class
Thread Safety in the C++ Standard Library