wxstring.tex

很牛的GUI源码wxWidgets-2.8.0.zip 可在多种平台下运行.

    //
  size_t find_last_not_of(const char* s, size_t nStart = npos) const;
    //
  size_t find_last_not_of(char ch, size_t nStart = npos) const;

    // All compare functions return a negative, zero or positive value
    // if the [sub]string is less, equal or greater than the compare() argument.

    // just like strcmp()
  int compare(const wxString& str) const;
    // comparison with a substring
  int compare(size_t nStart, size_t nLen, const wxString& str) const;
    // comparison of 2 substrings
  int compare(size_t nStart, size_t nLen,
              const wxString& str, size_t nStart2, size_t nLen2) const;
    // just like strcmp()
  int compare(const char* sz) const;
    // substring comparison with first nCount characters of sz
  int compare(size_t nStart, size_t nLen,
              const char* sz, size_t nCount = npos) const;

  // substring extraction
  wxString substr(size_t nStart = 0, size_t nLen = npos) const;
\end{verbatim}

%%%%% MEMBERS HERE %%%%%
\helponly{\insertatlevel{2}{

\wxheading{Members}

}}


\membersection{wxString::wxString}\label{wxstringconstruct}

\func{}{wxString}{\void}

Default constructor. Initializes the string to {\tt ""} (empty string).

\func{}{wxString}{\param{const wxString\&}{ x}}

Copy constructor.

\func{}{wxString}{\param{wxChar}{ ch}, \param{size\_t}{ n = 1}}

Constructs a string of {\it n} copies of character {\it ch}.

\func{}{wxString}{\param{const wxChar*}{ psz}, \param{size\_t}{ nLength = wxSTRING\_MAXLEN}}

Takes first {\it nLength} characters from the C string {\it psz}.
The default value of {\tt wxSTRING\_MAXLEN} means to take all the string.

Note that this constructor may be used even if {\it psz} points to a buffer
with binary data (i.e. containing {\tt NUL} characters) as long as you provide
the correct value for {\it nLength}. However, the default form of it works
only with strings without intermediate {\tt NUL}s because it uses 
{\tt strlen()} to calculate the effective length and it would not give correct
results otherwise.

\func{}{wxString}{\param{const unsigned char*}{ psz}, \param{size\_t}{ nLength = wxSTRING\_MAXLEN}}

For compilers using unsigned char: takes first {\it nLength} characters from the C string {\it psz}.
The default value of {\tt wxSTRING\_MAXLEN} means take all the string.
For ANSI builds only (note the use of {\tt char} instead of {\tt wxChar}).

\wxheading{Constructors with conversion}

The following constructors allow you to construct wxString from a wide string
in ANSI build or from a C string in Unicode build.

\func{}{wxString}{\param{const wchar\_t*}{ psz}, \param{wxMBConv\&}{ conv}, \param{size\_t}{ nLength = wxSTRING\_MAXLEN}}

Initializes the string from first \arg{nLength} characters of wide string. 
The default value of {\tt wxSTRING\_MAXLEN} means take all the string.
In ANSI build, \arg{conv}'s 
\helpref{WC2MB}{wxmbconvwc2mb} method is called to
convert \arg{psz} to wide string. It is ignored in Unicode build.

\func{}{wxString}{\param{const char*}{ psz}, \param{wxMBConv\&}{ conv}, \param{size\_t}{ nLength = wxSTRING\_MAXLEN}}

Initializes the string from first \arg{nLength} characters of C string.
The default value of {\tt wxSTRING\_MAXLEN} means take all the string.
In Unicode build, \arg{conv}'s 
\helpref{MB2WC}{wxmbconvmb2wc} method is called to
convert \arg{psz} to wide string. It is ignored in ANSI build.

\wxheading{See also}

\helpref{wxMBConv classes}{mbconvclasses}, \helpref{mb\_str}{wxstringmbstr},
\helpref{wc\_str}{wxstringwcstr}


\membersection{wxString::\destruct{wxString}}\label{wxstringdestruct}

\func{}{\destruct{wxString}}{\void}

String destructor. Note that this is not virtual, so wxString must not be inherited from.


\membersection{wxString::Alloc}\label{wxstringalloc}

\func{void}{Alloc}{\param{size\_t}{ nLen}}

Preallocate enough space for wxString to store {\it nLen} characters. This function
may be used to increase speed when the string is constructed by repeated
concatenation as in

\begin{verbatim}

// delete all vowels from the string
wxString DeleteAllVowels(const wxString& original)
{
    wxString result;

    size_t len = original.length();

    result.Alloc(len);

    for ( size_t n = 0; n < len; n++ )
    {
        if ( strchr("aeuio", tolower(original[n])) == NULL )
            result += original[n];
    }

    return result;
}

\end{verbatim}

because it will avoid the need to reallocate string memory many times (in case
of long strings). Note that it does not set the maximal length of a string - it
will still expand if more than {\it nLen} characters are stored in it. Also, it
does not truncate the existing string (use 
\helpref{Truncate()}{wxstringtruncate} for this) even if its current length is
greater than {\it nLen}


\membersection{wxString::Append}\label{wxstringappend}

\func{wxString\&}{Append}{\param{const wxChar*}{ psz}}

Concatenates {\it psz} to this string, returning a reference to it.

\func{wxString\&}{Append}{\param{wxChar}{ ch}, \param{int}{ count = 1}}

Concatenates character {\it ch} to this string, {\it count} times, returning a reference
to it.


\membersection{wxString::AfterFirst}\label{wxstringafterfirst}

\constfunc{wxString}{AfterFirst}{\param{wxChar}{ ch}}

Gets all the characters after the first occurrence of {\it ch}.
Returns the empty string if {\it ch} is not found.


\membersection{wxString::AfterLast}\label{wxstringafterlast}

\constfunc{wxString}{AfterLast}{\param{wxChar}{ ch}}

Gets all the characters after the last occurrence of {\it ch}.
Returns the whole string if {\it ch} is not found.


\membersection{wxString::BeforeFirst}\label{wxstringbeforefirst}

\constfunc{wxString}{BeforeFirst}{\param{wxChar}{ ch}}

Gets all characters before the first occurrence of {\it ch}.
Returns the whole string if {\it ch} is not found.


\membersection{wxString::BeforeLast}\label{wxstringbeforelast}

\constfunc{wxString}{BeforeLast}{\param{wxChar}{ ch}}

Gets all characters before the last occurrence of {\it ch}.
Returns the empty string if {\it ch} is not found.


\membersection{wxString::c\_str}\label{wxstringcstr}

\constfunc{const wxChar *}{c\_str}{\void}

Returns a pointer to the string data ({\tt const char*} in ANSI build,
{\tt const wchar\_t*} in Unicode build).

\wxheading{See also}

\helpref{mb\_str}{wxstringmbstr}, \helpref{wc\_str}{wxstringwcstr},
\helpref{fn\_str}{wxstringfnstr}


\membersection{wxString::Clear}\label{wxstringclear}

\func{void}{Clear}{\void}

Empties the string and frees memory occupied by it.

See also: \helpref{Empty}{wxstringempty}


\membersection{wxString::Cmp}\label{wxstringcmp}

\constfunc{int}{Cmp}{\param{const wxString\&}{ s}}

\constfunc{int}{Cmp}{\param{const wxChar*}{ psz}}

Case-sensitive comparison.

Returns a positive value if the string is greater than the argument, zero if
it is equal to it or a negative value if it is less than the argument (same semantics
as the standard {\it strcmp()} function).

See also \helpref{CmpNoCase}{wxstringcmpnocase}, \helpref{IsSameAs}{wxstringissameas}.


\membersection{wxString::CmpNoCase}\label{wxstringcmpnocase}

\constfunc{int}{CmpNoCase}{\param{const wxString\&}{ s}}

\constfunc{int}{CmpNoCase}{\param{const wxChar*}{ psz}}

Case-insensitive comparison.

Returns a positive value if the string is greater than the argument, zero if
it is equal to it or a negative value if it is less than the argument (same semantics
as the standard {\it strcmp()} function).

See also \helpref{Cmp}{wxstringcmp}, \helpref{IsSameAs}{wxstringissameas}.


\membersection{wxString::CompareTo}\label{wxstringcompareto}

\begin{verbatim}
enum wxString::caseCompare {exact, ignoreCase};
\end{verbatim}

\constfunc{int}{CompareTo}{\param{const wxChar*}{ psz}, \param{caseCompare}{ cmp = exact}}

Case-sensitive comparison. Returns 0 if equal, 1 if greater or -1 if less.

This is a wxWidgets 1.xx compatibility function; use \helpref{Cmp}{wxstringcmp} instead.


\membersection{wxString::Contains}\label{wxstringcontains}

\constfunc{bool}{Contains}{\param{const wxString\&}{ str}}

Returns \true if target appears anywhere in wxString; else \false.

This is a wxWidgets 1.xx compatibility function; you should not use it in new code.


\membersection{wxString::Empty}\label{wxstringempty}

\func{void}{Empty}{\void}

Makes the string empty, but doesn't free memory occupied by the string.

See also: \helpref{Clear()}{wxstringclear}.


\membersection{wxString::Find}\label{wxstringfind}

\constfunc{int}{Find}{\param{wxChar}{ ch}, \param{bool}{ fromEnd = false}}

Searches for the given character. Returns the starting index, or {\tt wxNOT\_FOUND} if not found.

\constfunc{int}{Find}{\param{const wxChar*}{ sz}}

Searches for the given string. Returns the starting index, or {\tt wxNOT\_FOUND} if not found.


\membersection{wxString::First}\label{wxstringfirst}

\func{int}{First}{\param{wxChar}{ c}}

\constfunc{int}{First}{\param{const wxChar*}{ psz}}

\constfunc{int}{First}{\param{const wxString\&}{ str}}

Same as \helpref{Find}{wxstringfind}.

This is a wxWidgets 1.xx compatibility function; you should not use it in new code.


\membersection{wxString::fn\_str}\label{wxstringfnstr}

\constfunc{const wchar\_t*}{fn\_str}{\void}

\constfunc{const char*}{fn\_str}{\void}

\constfunc{const wxCharBuffer}{fn\_str}{\void}

Returns string representation suitable for passing to OS' functions for
file handling. In ANSI build, this is same as \helpref{c\_str}{wxstringcstr}.
In Unicode build, returned value can be either wide character string
or C string in charset matching the {\tt wxConvFileName} object, depending on
the OS.

\wxheading{See also}

\helpref{wxMBConv}{wxmbconv},
\helpref{wc\_str}{wxstringwcstr}, \helpref{mb\_str}{wxstringwcstr}


\membersection{wxString::Format}\label{wxstringformat}

\func{static wxString}{Format}{\param{const wxChar }{*format}, \param{}{...}}

This static function returns the string containing the result of calling 
\helpref{Printf}{wxstringprintf} with the passed parameters on it.

\wxheading{See also}

\helpref{FormatV}{wxstringformatv}, \helpref{Printf}{wxstringprintf}


\membersection{wxString::FormatV}\label{wxstringformatv}

\func{static wxString}{FormatV}{\param{const wxChar }{*format}, \param{va\_list }{argptr}}

This static function returns the string containing the result of calling 
\helpref{PrintfV}{wxstringprintfv} with the passed parameters on it.

\wxheading{See also}

\helpref{Format}{wxstringformat}, \helpref{PrintfV}{wxstringprintfv}


\membersection{wxString::Freq}\label{wxstringfreq}

\constfunc{int}{Freq}{\param{wxChar }{ch}}

Returns the number of occurrences of {\it ch} in the string.

This is a wxWidgets 1.xx compatibility function; you should not use it in new code.


\membersection{wxString::FromAscii}\label{wxstringfromascii}

\func{static wxString }{FromAscii}{\param{const char*}{ s}}

\func{static wxString }{FromAscii}{\param{const char}{ c}}

Converts the string or character from an ASCII, 7-bit form
to the native wxString representation. Most useful when using
a Unicode build of wxWidgets (note the use of {\tt char} instead of {\tt wxChar}).
Use \helpref{wxString constructors}{wxstringconstruct} if you
need to convert from another charset.


\membersection{wxString::GetChar}\label{wxstringgetchar}

\constfunc{wxChar}{GetChar}{\param{size\_t}{ n}}

Returns the character at position {\it n} (read-only).


\membersection{wxString::GetData}\label{wxstringgetdata}

\constfunc{const wxChar*}{GetData}{\void}

wxWidgets compatibility conversion. Returns a constant pointer to the data in the string.


\membersection{wxString::GetWritableChar}\label{wxstringgetwritablechar}

\func{wxChar\&}{GetWritableChar}{\param{size\_t}{ n}}

Returns a reference to the character at position {\it n}.


\membersection{wxString::GetWriteBuf}\label{wxstringgetwritebuf}

\func{wxChar*}{GetWriteBuf}{\param{size\_t}{ len}}

Returns a writable buffer of at least {\it len} bytes.
It returns a pointer to a new memory block, and the
existing data will not be copied.

Call \helpref{wxString::UngetWriteBuf}{wxstringungetwritebuf} as soon as possible
to put the string back into a reasonable state.