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ST20 Embedded Toolset R2.0.5用于开发基于ST20芯片机顶盒软件的开发平台,2.0.5版本,国内找不到的.在国外论坛上花了N天才找到!

<P>The second member function deallocates any sequence currently
controlled by <CODE>*this</CODE>. It then
allocates a copy of the sequence controlled
by <CODE>newstr</CODE>. If <CODE>mode &amp; ios_base::in</CODE> is nonzero,
it sets the input buffer to begin reading
at the beginning of the sequence.
If <CODE>mode &amp; ios_base::out</CODE> is nonzero,
it sets the output buffer to begin
writing at the beginning of the sequence.</P>

<H3><A NAME="basic_stringbuf::traits_type"><CODE>basic_stringbuf::traits_type</CODE></A></H3>

<PRE>typedef Tr <B>traits_type</B>;</PRE>

<P>The type is a synonym for the template parameter <CODE>Tr</CODE>.</P>

<H3><A NAME="basic_stringbuf::underflow"><CODE>basic_stringbuf::underflow</CODE></A></H3>

<PRE>virtual int_type <B>underflow</B>();</PRE>

<P>The protected virtual member function endeavors to extract the current
element <CODE>byte</CODE> from the
<A HREF="streambu.html#input buffer">input buffer</A>,
then advance the current stream position, and return the element as
<CODE>traits_type::<A HREF="string2.html#char_traits::to_int_type">to_int_type</A>(byte)</CODE>.
It can do so in only one way:
If a <A HREF="streambu.html#read position">read position</A>
is available, it takes <CODE>byte</CODE> as the element stored
in the read position and advances the next pointer for the input buffer.</P>

<P>If the function cannot succeed, it returns
<CODE>traits_type::<A HREF="string2.html#char_traits::eof">eof</A>()</CODE>. Otherwise,
it returns the current element in the input stream,
converted as described above.</P>

<H2><A NAME="basic_istringstream"><CODE>basic_istringstream</CODE></A></H2>

<PRE>template &lt;class Elem,
    class Tr = char_traits&lt;Elem&gt;,
    class Alloc = allocator&lt;Elem&gt; &gt;
    class <B>basic_istringstream</B>
        : public basic_istream&lt;Elem, Tr&gt; {
public:
    typedef Alloc <B><A HREF="#basic_istringstream::allocator_type">allocator_type</A></B>;
    explicit <B><A HREF="#basic_istringstream::basic_istringstream">basic_istringstream</A></B>(
        ios_base::openmode mode = ios_base::in);
    explicit <B><A HREF="#basic_istringstream::basic_istringstream">basic_istringstream</A></B>(
        const basic_string&lt;Elem, Tr, Alloc&gt;&amp; str,
        ios_base::openmode mode = ios_base::in);
    basic_stringbuf&lt;Elem, Tr, Alloc&gt; *<B><A HREF="#basic_istringstream::rdbuf">rdbuf</A></B>() const;
    basic_string&lt;Elem, Tr, Alloc&gt; <B><A HREF="#basic_istringstream::str">str</A></B>();
    void <B><A HREF="#basic_istringstream::str">str</A></B>(const basic_string&lt;Elem, Tr, Alloc&gt;&amp; newstr);
    };</PRE>

<P>The template class describes an object that controls
extraction of elements and encoded objects from a
<A HREF="streambu.html#stream buffer">stream buffer</A> of class
<CODE><A HREF="#basic_stringbuf">basic_stringbuf</A>&lt;Elem, Tr, Alloc&gt;</CODE>,
with elements of type <CODE>Elem</CODE>, whose
<A HREF="string2.html#character traits">character traits</A> are determined
by the class <CODE>Tr</CODE>, and whose elements are allocated by
an allocator of class <CODE>Alloc</CODE>. The object stores an object of class
<CODE>basic_stringbuf&lt;Elem, Tr, Alloc&gt;</CODE>.</P>

<H3><A NAME="basic_istringstream::allocator_type"><CODE>basic_istringstream::allocator_type</CODE></A></H3>

<PRE>typedef Alloc <B>allocator_type</B>;</PRE>

<P>The type is a synonym for the template parameter <CODE>Alloc</CODE>.</P>

<H3><A NAME="basic_istringstream::basic_istringstream"><CODE>basic_istringstream::basic_istringstream</CODE></A></H3>

<PRE>explicit <B>basic_istringstream</B>(
    ios_base::openmode mode = ios_base::in);
explicit <B>basic_istringstream</B>(
    const basic_string&lt;Elem, Tr, Alloc&gt;&amp; str,
    ios_base::openmode mode = ios_base::in);</PRE>

<P>The first constructor initializes the base class by calling
<CODE><A HREF="istream.html#basic_istream::basic_istream">basic_istream</A>(sb)</CODE>,
where <CODE>sb</CODE> is the stored object of class
<CODE><A HREF="#basic_stringbuf">basic_stringbuf</A>&lt;Elem, Tr, Alloc&gt;</CODE>.
It also initializes <CODE>sb</CODE> by calling
<CODE><A HREF="#basic_stringbuf::basic_stringbuf">basic_stringbuf</A>&lt;Elem,
Tr, Alloc&gt;(mode | ios_base::in)</CODE>.</P>

<P>The second constructor initializes the base class by calling
<CODE>basic_istream(sb)</CODE>.
It also initializes <CODE>sb</CODE> by calling
<CODE><A HREF="#basic_stringbuf::basic_stringbuf">basic_stringbuf</A>&lt;Elem,
Tr, Alloc&gt;(str, mode | ios_base::in)</CODE>.</P>

<H3><A NAME="basic_istringstream::rdbuf"><CODE>basic_istringstream::rdbuf</CODE></A></H3>

<PRE>basic_stringbuf&lt;Elem, Tr, Alloc&gt; *<B>rdbuf</B>() const</PRE>

<P>The member function returns the address of the stored
stream buffer, of type pointer to
<CODE><A HREF="#basic_stringbuf">basic_stringbuf</A>&lt;Elem,
Tr, Alloc&gt;</CODE>.</P>

<H3><A NAME="basic_istringstream::str"><CODE>basic_istringstream::str</CODE></A></H3>

<PRE>basic_string&lt;Elem, Tr, Alloc&gt; <B>str</B>() const;
void <B>str</B>(const basic_string&lt;Elem, Tr, Alloc&gt;&amp; newstr);</PRE>

<P>The first member function returns
<CODE><A HREF="#basic_istringstream::rdbuf">rdbuf</A>()-&gt;
<A HREF="#basic_stringbuf::str">str</A>()</CODE>.
The second member function calls <CODE>rdbuf()-&gt; str(newstr)</CODE>.</P>

<H2><A NAME="basic_ostringstream"><CODE>basic_ostringstream</CODE></A></H2>

<PRE>template &lt;class Elem,
    class Tr = char_traits&lt;Elem&gt;,
    class Alloc = allocator&lt;Elem&gt; &gt;
    class <B>basic_ostringstream</B>
        : public basic_ostream&lt;Elem, Tr&gt; {
public:
    explicit <B><A HREF="#basic_ostringstream::basic_ostringstream">basic_ostringstream</A></B>(
        ios_base::openmode mode = ios_base::out);
    explicit <B><A HREF="#basic_ostringstream::basic_ostringstream">basic_ostringstream</A></B>(
        const basic_string&lt;Elem, Tr, Alloc&gt;&amp; str,
        ios_base::openmode mode = ios_base::out);
    basic_stringbuf&lt;Elem, Tr, Alloc&gt; *<B><A HREF="#basic_ostringstream::rdbuf">rdbuf</A></B>() const;
    basic_string&lt;Elem, Tr, Alloc&gt; <B><A HREF="#basic_ostringstream::str">str</A></B>();
    void <B><A HREF="#basic_ostringstream::str">str</A></B>(const basic_string&lt;Elem, Tr, Alloc&gt;&amp; newstr);
    };</PRE>

<P>The template class describes an object that controls
insertion of elements and encoded objects into a
<A HREF="streambu.html#stream buffer">stream buffer</A> of class
<CODE><A HREF="#basic_stringbuf">basic_stringbuf</A>&lt;Elem, Tr, Alloc&gt;</CODE>,
with elements of type <CODE>Elem</CODE>, whose
<A HREF="string2.html#character traits">character traits</A> are determined
by the class <CODE>Tr</CODE>, and whose elements are allocated by
an allocator of class <CODE>Alloc</CODE>. The object stores an object of class
<CODE>basic_stringbuf&lt;Elem, Tr, Alloc&gt;</CODE>.</P>

<H3><A NAME="basic_ostringstream::allocator_type"><CODE>basic_ostringstream::allocator_type</CODE></A></H3>

<PRE>typedef Alloc <B>allocator_type</B>;</PRE>

<P>The type is a synonym for the template parameter <CODE>Alloc</CODE>.</P>

<H3><A NAME="basic_ostringstream::basic_ostringstream"><CODE>basic_ostringstream::basic_ostringstream</CODE></A></H3>

<PRE>explicit <B>basic_ostringstream</B>(
    ios_base::openmode mode = ios_base::out);
explicit <B>basic_ostringstream</B>(
    const basic_string&lt;Elem, Tr, Alloc&gt;&amp; str,
    ios_base::openmode mode = ios_base::out);</PRE>

<P>The first constructor initializes the base class by calling
<CODE><A HREF="ostream.html#basic_ostream::basic_ostream">basic_ostream</A>(sb)</CODE>,
where <CODE>sb</CODE> is the stored object of class
<CODE><A HREF="#basic_stringbuf">basic_stringbuf</A>&lt;Elem, Tr, Alloc&gt;</CODE>.
It also initializes <CODE>sb</CODE> by calling
<CODE><A HREF="#basic_stringbuf::basic_stringbuf">basic_stringbuf</A>&lt;Elem,
Tr, Alloc&gt;(mode | ios_base::out)</CODE>.</P>

<P>The second constructor initializes the base class by calling
<CODE>basic_ostream(sb)</CODE>.
It also initializes <CODE>sb</CODE> by calling
<CODE><A HREF="#basic_stringbuf::basic_stringbuf">basic_stringbuf</A>&lt;Elem,
Tr, Alloc&gt;(str, mode | ios_base::out)</CODE>.</P>

<H3><A NAME="basic_ostringstream::rdbuf"><CODE>basic_ostringstream::rdbuf</CODE></A></H3>

<PRE>basic_stringbuf&lt;Elem, Tr, Alloc&gt; *<B>rdbuf</B>() const</PRE>

<P>The member function returns the address of the stored
stream buffer, of type pointer to
<CODE><A HREF="#basic_stringbuf">basic_stringbuf</A>&lt;Elem,
Tr, Alloc&gt;</CODE>.</P>

<H3><A NAME="basic_ostringstream::str"><CODE>basic_ostringstream::str</CODE></A></H3>

<PRE>basic_string&lt;Elem, Tr, Alloc&gt; <B>str</B>() const;
void <B>str</B>(const basic_string&lt;Elem, Tr, Alloc&gt;&amp; newstr);</PRE>

<P>The first member function returns
<CODE><A HREF="#basic_ostringstream::rdbuf">rdbuf</A>()-&gt;
<A HREF="#basic_stringbuf::str">str</A>()</CODE>.
The second member function calls <CODE>rdbuf()-&gt; str(newstr)</CODE>.</P>

<H2><A NAME="basic_stringstream"><CODE>basic_stringstream</CODE></A></H2>

<PRE>template &lt;class Elem,
    class Tr = char_traits&lt;Elem&gt;,
    class Alloc = allocator&lt;Elem&gt; &gt;
    class <B>basic_stringstream</B>
        : public basic_iostream&lt;Elem, Tr&gt; {
public:
    typedef Alloc <B><A HREF="#basic_stringstream::allocator_type">allocator_type</A></B>;
    explicit <B><A HREF="#basic_stringstream::basic_stringstream">basic_stringstream</A></B>(
        ios_base::openmode mode =
            ios_base::in | ios_base::out);
    explicit <B><A HREF="#basic_stringstream::basic_stringstream">basic_stringstream</A></B>(
        const basic_string&lt;Elem, Tr, Alloc&gt;&amp; str,
        ios_base::openmode mode =
            ios_base::in | ios_base::out);
    basic_stringbuf&lt;Elem, Tr, Alloc&gt; *<B><A HREF="#basic_stringstream::rdbuf">rdbuf</A></B>() const;
    basic_string&lt;Elem, Tr, Alloc&gt; <B><A HREF="#basic_stringstream::str">str</A></B>();
    void <B><A HREF="#basic_stringstream::str">str</A></B>(const basic_string&lt;Elem, Tr, Alloc&gt;&amp; newstr);
    };</PRE>

<P>The template class describes an object that controls
insertion and extraction of elements and encoded objects using a
<A HREF="streambu.html#stream buffer">stream buffer</A> of class
<CODE><A HREF="#basic_stringbuf">basic_stringbuf</A>&lt;Elem, Tr, Alloc&gt;</CODE>,
with elements of type <CODE>Elem</CODE>, whose
<A HREF="string2.html#character traits">character traits</A> are determined
by the class <CODE>Tr</CODE>, and whose elements are allocated by
an allocator of class <CODE>Alloc</CODE>. The object stores an object of class
<CODE>basic_stringbuf&lt;Elem, Tr, Alloc&gt;</CODE>.</P>

<H3><A NAME="basic_stringstream::allocator_type"><CODE>basic_stringstream::allocator_type</CODE></A></H3>

<PRE>typedef Alloc <B>allocator_type</B>;</PRE>

<P>The type is a synonym for the template parameter <CODE>Alloc</CODE>.</P>

<H3><A NAME="basic_stringstream::basic_stringstream"><CODE>basic_stringstream::basic_stringstream</CODE></A></H3>

<PRE>explicit <B>basic_stringstream</B>(
    ios_base::openmode mode =
        ios_base::in | ios_base::out);
explicit <B>basic_stringstream</B>(
    const basic_string&lt;Elem, Tr, Alloc&gt;&amp; str,
    ios_base::openmode mode =
         ios_base::in | ios_base::out);</PRE>

<P>The first constructor initializes the base class by calling
<CODE><A HREF="istream.html#basic_iostream">basic_iostream</A>(sb)</CODE>,
where <CODE>sb</CODE> is the stored object of class
<CODE><A HREF="#basic_stringbuf">basic_stringbuf</A>&lt;Elem, Tr, Alloc&gt;</CODE>.
It also initializes <CODE>sb</CODE> by calling
<CODE><A HREF="#basic_stringbuf::basic_stringbuf">basic_stringbuf</A>&lt;Elem,
Tr, Alloc&gt;(mode)</CODE>.</P>

<P>The second constructor initializes the base class by calling
<CODE>basic_iostream(sb)</CODE>.
It also initializes <CODE>sb</CODE> by calling
<CODE><A HREF="#basic_stringbuf::basic_stringbuf">basic_stringbuf</A>&lt;Elem,
Tr, Alloc&gt;(str, mode)</CODE>.</P>

<H3><A NAME="basic_stringstream::rdbuf"><CODE>basic_stringstream::rdbuf</CODE></A></H3>

<PRE>basic_stringbuf&lt;Elem, Tr, Alloc&gt; *<B>rdbuf</B>() const</PRE>

<P>The member function returns the address of the stored
stream buffer, of type pointer to
<CODE><A HREF="#basic_stringbuf">basic_stringbuf</A>&lt;Elem,
Tr, Alloc&gt;</CODE>.</P>

<H3><A NAME="basic_stringstream::str"><CODE>basic_stringstream::str</CODE></A></H3>

<PRE>basic_string&lt;Elem, Tr, Alloc&gt; <B>str</B>() const;
void <B>str</B>(const basic_string&lt;Elem, Tr, Alloc&gt;&amp; newstr);</PRE>

<P>The first member function returns
<CODE><A HREF="#basic_stringstream::rdbuf">rdbuf</A>()-&gt;
<A HREF="#basic_stringbuf::str">str</A>()</CODE>.
The second member function calls <CODE>rdbuf()-&gt; str(newstr)</CODE>.</P>

<H2><A NAME="istringstream"><CODE>istringstream</CODE></A></H2>

<PRE>typedef basic_istringstream&lt;char&gt; <B>istringstream</B>;</PRE>

<P>The type is a synonym for template class
<A HREF="#basic_istringstream"><CODE>basic_istringstream</CODE></A>, specialized
for elements of type <I>char.</I></P>

<H2><A NAME="ostringstream"><CODE>ostringstream</CODE></A></H2>

<PRE>typedef basic_ostringstream&lt;char&gt; <B>ostringstream</B>;</PRE>

<P>The type is a synonym for template class
<A HREF="#basic_ostringstream"><CODE>basic_ostringstream</CODE></A>, specialized
for elements of type <I>char.</I></P>

<H2><A NAME="stringbuf"><CODE>stringbuf</CODE></A></H2>

<PRE>typedef basic_stringbuf&lt;char&gt; <B>stringbuf</B>;</PRE>

<P>The type is a synonym for template class
<A HREF="#basic_stringbuf"><CODE>basic_stringbuf</CODE></A>, specialized
for elements of type <I>char.</I></P>

<H2><A NAME="stringstream"><CODE>stringstream</CODE></A></H2>

<PRE>typedef basic_stringstream&lt;char&gt; <B>stringstream</B>;</PRE>

<P>The type is a synonym for template class
<A HREF="#basic_stringstream"><CODE>basic_stringstream</CODE></A>, specialized
for elements of type <I>char.</I></P>

<H2><A NAME="wistringstream"><CODE>wistringstream</CODE></A></H2>

<PRE>typedef basic_istringstream&lt;wchar_t&gt; <B>wistringstream</B>;</PRE>

<P>The type is a synonym for template class
<A HREF="#basic_istringstream"><CODE>basic_istringstream</CODE></A>, specialized
for elements of type <CODE>wchar_t</CODE>.</P>

<H2><A NAME="wostringstream"><CODE>wostringstream</CODE></A></H2>

<PRE>typedef basic_ostringstream&lt;wchar_t&gt; <B>wostringstream</B>;</PRE>

<P>The type is a synonym for template class
<A HREF="#basic_ostringstream"><CODE>basic_ostringstream</CODE></A>, specialized
for elements of type <CODE>wchar_t</CODE>.</P>

<H2><A NAME="wstringbuf"><CODE>wstringbuf</CODE></A></H2>

<PRE>typedef basic_stringbuf&lt;wchar_t&gt; <B>wstringbuf</B>;</PRE>

<P>The type is a synonym for template class
<A HREF="#basic_stringbuf"><CODE>basic_stringbuf</CODE></A>, specialized
for elements of type <CODE>wchar_t</CODE>.</P>

<H2><A NAME="wstringstream"><CODE>wstringstream</CODE></A></H2>

<PRE>typedef basic_stringstream&lt;wchar_t&gt; <B>wstringstream</B>;</PRE>

<P>The type is a synonym for template class
<A HREF="#basic_stringstream"><CODE>basic_stringstream</CODE></A>, specialized
for elements of type <CODE>wchar_t</CODE>.</P>

<HR>
<P>See also the
<B><A HREF="index.html#Table of Contents">Table of Contents</A></B> and the
<B><A HREF="_index.html">Index</A></B>.</P>

<P><I>
<A HREF="crit_pjp.html">Copyright</A> &#169; 1992-2002
by P.J. Plauger. All rights reserved.</I></P>

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