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32<td align="right" valign="center"><img src="logo32.png" align="right" width="64" height="32" border="0"></td></tr></table><h1 align=center>QDateTime Class Reference</h1>
33
34<p>The QDateTime class provides date and time functions.
35<a href="#details">More...</a>
36<p>All the functions in this class are <a href="threads.html#reentrant">reentrant</a> when Qt is built with thread support.</p>
37<p><tt>#include &lt;<a href="qdatetime-h.html">qdatetime.h</a>&gt;</tt>
38<p><a href="qdatetime-members.html">List of all member functions.</a>
39<h2>Public Members</h2>
40<ul>
41<li class=fn><a href="#QDateTime"><b>QDateTime</b></a> ()</li>
42<li class=fn><a href="#QDateTime-2"><b>QDateTime</b></a> ( const&nbsp;QDate&nbsp;&amp;&nbsp;date )</li>
43<li class=fn><a href="#QDateTime-3"><b>QDateTime</b></a> ( const&nbsp;QDate&nbsp;&amp;&nbsp;date, const&nbsp;QTime&nbsp;&amp;&nbsp;time )</li>
44<li class=fn>bool <a href="#isNull"><b>isNull</b></a> () const</li>
45<li class=fn>bool <a href="#isValid"><b>isValid</b></a> () const</li>
46<li class=fn>QDate <a href="#date"><b>date</b></a> () const</li>
47<li class=fn>QTime <a href="#time"><b>time</b></a> () const</li>
48<li class=fn>uint <a href="#toTime_t"><b>toTime_t</b></a> () const</li>
49<li class=fn>void <a href="#setDate"><b>setDate</b></a> ( const&nbsp;QDate&nbsp;&amp;&nbsp;date )</li>
50<li class=fn>void <a href="#setTime"><b>setTime</b></a> ( const&nbsp;QTime&nbsp;&amp;&nbsp;time )</li>
51<li class=fn>void <a href="#setTime_t-2"><b>setTime_t</b></a> ( uint&nbsp;secsSince1Jan1970UTC )</li>
52<li class=fn>void <a href="#setTime_t"><b>setTime_t</b></a> ( uint&nbsp;secsSince1Jan1970UTC, Qt::TimeSpec&nbsp;ts )</li>
53<li class=fn>QString <a href="#toString-2"><b>toString</b></a> ( Qt::DateFormat&nbsp;f = Qt::TextDate ) const</li>
54<li class=fn>QString <a href="#toString"><b>toString</b></a> ( const&nbsp;QString&nbsp;&amp;&nbsp;format ) const</li>
55<li class=fn>QDateTime <a href="#addDays"><b>addDays</b></a> ( int&nbsp;ndays ) const</li>
56<li class=fn>QDateTime <a href="#addMonths"><b>addMonths</b></a> ( int&nbsp;nmonths ) const</li>
57<li class=fn>QDateTime <a href="#addYears"><b>addYears</b></a> ( int&nbsp;nyears ) const</li>
58<li class=fn>QDateTime <a href="#addSecs"><b>addSecs</b></a> ( int&nbsp;nsecs ) const</li>
59<li class=fn>int <a href="#daysTo"><b>daysTo</b></a> ( const&nbsp;QDateTime&nbsp;&amp;&nbsp;dt ) const</li>
60<li class=fn>int <a href="#secsTo"><b>secsTo</b></a> ( const&nbsp;QDateTime&nbsp;&amp;&nbsp;dt ) const</li>
61<li class=fn>bool <a href="#operator-eq-eq"><b>operator==</b></a> ( const&nbsp;QDateTime&nbsp;&amp;&nbsp;dt ) const</li>
62<li class=fn>bool <a href="#operator!-eq"><b>operator!=</b></a> ( const&nbsp;QDateTime&nbsp;&amp;&nbsp;dt ) const</li>
63<li class=fn>bool <a href="#operator-lt"><b>operator&lt;</b></a> ( const&nbsp;QDateTime&nbsp;&amp;&nbsp;dt ) const</li>
64<li class=fn>bool <a href="#operator-lt-eq"><b>operator&lt;=</b></a> ( const&nbsp;QDateTime&nbsp;&amp;&nbsp;dt ) const</li>
65<li class=fn>bool <a href="#operator-gt"><b>operator&gt;</b></a> ( const&nbsp;QDateTime&nbsp;&amp;&nbsp;dt ) const</li>
66<li class=fn>bool <a href="#operator-gt-eq"><b>operator&gt;=</b></a> ( const&nbsp;QDateTime&nbsp;&amp;&nbsp;dt ) const</li>
67</ul>
68<h2>Static Public Members</h2>
69<ul>
70<li class=fn>QDateTime <a href="#currentDateTime-2"><b>currentDateTime</b></a> ()</li>
71<li class=fn>QDateTime <a href="#currentDateTime"><b>currentDateTime</b></a> ( Qt::TimeSpec&nbsp;ts )</li>
72<li class=fn>QDateTime <a href="#fromString"><b>fromString</b></a> ( const&nbsp;QString&nbsp;&amp;&nbsp;s, Qt::DateFormat&nbsp;f = Qt::TextDate )</li>
73</ul>
74<h2>Related Functions</h2>
75<ul>
76<li class=fn>QDataStream &amp; <a href="#operator-lt-lt"><b>operator&lt;&lt;</b></a> ( QDataStream&nbsp;&amp;&nbsp;s, const&nbsp;QDateTime&nbsp;&amp;&nbsp;dt )</li>
77<li class=fn>QDataStream &amp; <a href="#operator-gt-gt"><b>operator&gt;&gt;</b></a> ( QDataStream&nbsp;&amp;&nbsp;s, QDateTime&nbsp;&amp;&nbsp;dt )</li>
78</ul>
79<hr><a name="details"></a><h2>Detailed Description</h2>
80
81
82
83The QDateTime class provides date and time functions.
84<p>
85
86<p> A QDateTime object contains a calendar date and a clock time (a
87"datetime"). It is a combination of the <a href="qdate.html">QDate</a> and <a href="qtime.html">QTime</a> classes.
88It can read the current datetime from the system clock. It
89provides functions for comparing datetimes and for manipulating a
90datetime by adding a number of seconds, days, months or years.
91<p> A QDateTime object is typically created either by giving a date
92and time explicitly in the constructor, or by using the static
93function <a href="#currentDateTime">currentDateTime</a>(), which returns a QDateTime object set
94to the system clock's time. The date and time can be changed with
95<a href="#setDate">setDate</a>() and <a href="#setTime">setTime</a>(). A datetime can also be set using the
96<a href="#setTime_t">setTime_t</a>() function, which takes a POSIX-standard "number of
97seconds since 00:00:00 on January 1, 1970" value. The <a href="#fromString">fromString</a>()
98function returns a QDateTime given a string and a date format
99which is used to interpret the date within the string.
100<p> The <a href="#date">date</a>() and <a href="#time">time</a>() functions provide access to the date and
101time parts of the datetime. The same information is provided in
102textual format by the <a href="#toString">toString</a>() function.
103<p> QDateTime provides a full set of operators to compare two
104QDateTime objects where smaller means earlier and larger means
105later.
106<p> You can increment (or decrement) a datetime by a given number of
107seconds using <a href="#addSecs">addSecs</a>() or days using <a href="#addDays">addDays</a>(). Similarly you can
108use <a href="#addMonths">addMonths</a>() and <a href="#addYears">addYears</a>(). The <a href="#daysTo">daysTo</a>() function returns the
109number of days between two datetimes, and <a href="#secsTo">secsTo</a>() returns the
110number of seconds between two datetimes.
111<p> The range of a datetime object is constrained to the ranges of the
112<a href="qdate.html">QDate</a> and <a href="qtime.html">QTime</a> objects which it embodies.
113<p> <p>See also <a href="qdate.html">QDate</a>, <a href="qtime.html">QTime</a>, <a href="qdatetimeedit.html">QDateTimeEdit</a>, and <a href="time.html">Time and Date</a>.
114
115<hr><h2>Member Function Documentation</h2>
116<h3 class=fn><a name="QDateTime"></a>QDateTime::QDateTime ()
117</h3>
118
119<p> Constructs a null datetime (i.e. null date and null time). A null
120datetime is invalid, since the date is invalid.
121<p> <p>See also <a href="#isValid">isValid</a>().
122
123<h3 class=fn><a name="QDateTime-2"></a>QDateTime::QDateTime ( const&nbsp;<a href="qdate.html">QDate</a>&nbsp;&amp;&nbsp;date )
124</h3>
125Constructs a datetime with date <em>date</em> and null (but valid) time
126(00:00:00.000).
127
128<h3 class=fn><a name="QDateTime-3"></a>QDateTime::QDateTime ( const&nbsp;<a href="qdate.html">QDate</a>&nbsp;&amp;&nbsp;date, const&nbsp;<a href="qtime.html">QTime</a>&nbsp;&amp;&nbsp;time )
129</h3>
130Constructs a datetime with date <em>date</em> and time <em>time</em>.
131
132<h3 class=fn><a href="qdatetime.html">QDateTime</a> <a name="addDays"></a>QDateTime::addDays ( int&nbsp;ndays ) const
133</h3>
134Returns a QDateTime object containing a datetime <em>ndays</em> days
135later than the datetime of this object (or earlier if <em>ndays</em> is
136negative).
137<p> <p>See also <a href="#daysTo">daysTo</a>(), <a href="#addMonths">addMonths</a>(), <a href="#addYears">addYears</a>(), and <a href="#addSecs">addSecs</a>().
138
139<h3 class=fn><a href="qdatetime.html">QDateTime</a> <a name="addMonths"></a>QDateTime::addMonths ( int&nbsp;nmonths ) const
140</h3>
141Returns a QDateTime object containing a datetime <em>nmonths</em> months
142later than the datetime of this object (or earlier if <em>nmonths</em>
143is negative).
144<p> <p>See also <a href="#daysTo">daysTo</a>(), <a href="#addDays">addDays</a>(), <a href="#addYears">addYears</a>(), and <a href="#addSecs">addSecs</a>().
145
146<h3 class=fn><a href="qdatetime.html">QDateTime</a> <a name="addSecs"></a>QDateTime::addSecs ( int&nbsp;nsecs ) const
147</h3>
148Returns a QDateTime object containing a datetime <em>nsecs</em> seconds
149later than the datetime of this object (or earlier if <em>nsecs</em> is
150negative).
151<p> <p>See also <a href="#secsTo">secsTo</a>(), <a href="#addDays">addDays</a>(), <a href="#addMonths">addMonths</a>(), and <a href="#addYears">addYears</a>().
152
153<p>Example: <a href="listviews-example.html#x136">listviews/listviews.cpp</a>.
154<h3 class=fn><a href="qdatetime.html">QDateTime</a> <a name="addYears"></a>QDateTime::addYears ( int&nbsp;nyears ) const
155</h3>
156Returns a QDateTime object containing a datetime <em>nyears</em> years
157later than the datetime of this object (or earlier if <em>nyears</em> is
158negative).
159<p> <p>See also <a href="#daysTo">daysTo</a>(), <a href="#addDays">addDays</a>(), <a href="#addMonths">addMonths</a>(), and <a href="#addSecs">addSecs</a>().
160
161<h3 class=fn><a href="qdatetime.html">QDateTime</a> <a name="currentDateTime"></a>QDateTime::currentDateTime ( <a href="qt.html#TimeSpec-enum">Qt::TimeSpec</a>&nbsp;ts )<tt> [static]</tt>
162</h3>
163Returns the current datetime, as reported by the system clock, for the
164TimeSpec <em>ts</em>. The default TimeSpec is LocalTime.
165<p> <p>See also <a href="qdate.html#currentDate">QDate::currentDate</a>(), <a href="qtime.html#currentTime">QTime::currentTime</a>(), and <a href="qt.html#TimeSpec-enum">Qt::TimeSpec</a>.
166
167<p>Example: <a href="listviews-example.html#x137">listviews/listviews.cpp</a>.
168<h3 class=fn><a href="qdatetime.html">QDateTime</a> <a name="currentDateTime-2"></a>QDateTime::currentDateTime ()<tt> [static]</tt>
169</h3>
170This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
171<p> Returns the current datetime, as reported by the system clock.
172<p> <p>See also <a href="qdate.html#currentDate">QDate::currentDate</a>() and <a href="qtime.html#currentTime">QTime::currentTime</a>().
173
174<h3 class=fn><a href="qdate.html">QDate</a> <a name="date"></a>QDateTime::date () const
175</h3>
176
177<p> Returns the date part of the datetime.
178<p> <p>See also <a href="#setDate">setDate</a>() and <a href="#time">time</a>().
179
180<h3 class=fn>int <a name="daysTo"></a>QDateTime::daysTo ( const&nbsp;<a href="qdatetime.html">QDateTime</a>&nbsp;&amp;&nbsp;dt ) const
181</h3>
182Returns the number of days from this datetime to <em>dt</em> (which is
183negative if <em>dt</em> is earlier than this datetime).
184<p> <p>See also <a href="#addDays">addDays</a>() and <a href="#secsTo">secsTo</a>().
185
186<h3 class=fn><a href="qdatetime.html">QDateTime</a> <a name="fromString"></a>QDateTime::fromString ( const&nbsp;<a href="qstring.html">QString</a>&nbsp;&amp;&nbsp;s, <a href="qt.html#DateFormat-enum">Qt::DateFormat</a>&nbsp;f = Qt::TextDate )<tt> [static]</tt>
187</h3>
188Returns the QDateTime represented by the string <em>s</em>, using the
189format <em>f</em>, or an invalid datetime if this is not possible.
190<p> Note for <a href="qt.html#DateFormat-enum">Qt::TextDate</a>: It is recommended that you use the
191English short month names (e.g. "Jan"). Although localized month
192names can also be used, they depend on the user's locale settings.
193<p> <b>Warning:</b> Note that <a href="qt.html#DateFormat-enum">Qt::LocalDate</a> cannot be used here.
194
195<h3 class=fn>bool <a name="isNull"></a>QDateTime::isNull () const
196</h3>
197
198<p> Returns TRUE if both the date and the time are null; otherwise
199returns FALSE. A null datetime is invalid.
200<p> <p>See also <a href="qdate.html#isNull">QDate::isNull</a>() and <a href="qtime.html#isNull">QTime::isNull</a>().
201
202<h3 class=fn>bool <a name="isValid"></a>QDateTime::isValid () const
203</h3>
204
205<p> Returns TRUE if both the date and the time are valid; otherwise
206returns FALSE.
207<p> <p>See also <a href="qdate.html#isValid">QDate::isValid</a>() and <a href="qtime.html#isValid">QTime::isValid</a>().
208
209<h3 class=fn>bool <a name="operator!-eq"></a>QDateTime::operator!= ( const&nbsp;<a href="qdatetime.html">QDateTime</a>&nbsp;&amp;&nbsp;dt ) const
210</h3>
211Returns TRUE if this datetime is different from <em>dt</em>; otherwise
212returns FALSE.
213<p> <p>See also <a href="#operator-eq-eq">operator==</a>().
214
215<h3 class=fn>bool <a name="operator-lt"></a>QDateTime::operator&lt; ( const&nbsp;<a href="qdatetime.html">QDateTime</a>&nbsp;&amp;&nbsp;dt ) const
216</h3>
217Returns TRUE if this datetime is earlier than <em>dt</em>; otherwise
218returns FALSE.
219
220<h3 class=fn>bool <a name="operator-lt-eq"></a>QDateTime::operator&lt;= ( const&nbsp;<a href="qdatetime.html">QDateTime</a>&nbsp;&amp;&nbsp;dt ) const
221</h3>
222Returns TRUE if this datetime is earlier than or equal to <em>dt</em>;
223otherwise returns FALSE.
224
225<h3 class=fn>bool <a name="operator-eq-eq"></a>QDateTime::operator== ( const&nbsp;<a href="qdatetime.html">QDateTime</a>&nbsp;&amp;&nbsp;dt ) const
226</h3>
227Returns TRUE if this datetime is equal to <em>dt</em>; otherwise returns FALSE.
228<p> <p>See also <a href="#operator!-eq">operator!=</a>().
229
230<h3 class=fn>bool <a name="operator-gt"></a>QDateTime::operator&gt; ( const&nbsp;<a href="qdatetime.html">QDateTime</a>&nbsp;&amp;&nbsp;dt ) const
231</h3>
232Returns TRUE if this datetime is later than <em>dt</em>; otherwise
233returns FALSE.
234
235<h3 class=fn>bool <a name="operator-gt-eq"></a>QDateTime::operator&gt;= ( const&nbsp;<a href="qdatetime.html">QDateTime</a>&nbsp;&amp;&nbsp;dt ) const
236</h3>
237Returns TRUE if this datetime is later than or equal to <em>dt</em>;
238otherwise returns FALSE.
239
240<h3 class=fn>int <a name="secsTo"></a>QDateTime::secsTo ( const&nbsp;<a href="qdatetime.html">QDateTime</a>&nbsp;&amp;&nbsp;dt ) const
241</h3>
242Returns the number of seconds from this datetime to <em>dt</em> (which
243is negative if <em>dt</em> is earlier than this datetime).
244<p> Example:
245<pre>
246 QDateTime dt = QDateTime::<a href="#currentDateTime">currentDateTime</a>();
247 QDateTime xmas( QDate(dt.<a href="#date">date</a>().year(),12,24), QTime(17,00) );
248 <a href="qapplication.html#qDebug">qDebug</a>( "There are %d seconds to Christmas", dt.<a href="#secsTo">secsTo</a>(xmas) );
249 </pre>
250
251<p> <p>See also <a href="#addSecs">addSecs</a>(), <a href="#daysTo">daysTo</a>(), and <a href="qtime.html#secsTo">QTime::secsTo</a>().
252
253<h3 class=fn>void <a name="setDate"></a>QDateTime::setDate ( const&nbsp;<a href="qdate.html">QDate</a>&nbsp;&amp;&nbsp;date )
254</h3>
255
256<p> Sets the date part of this datetime to <em>date</em>.
257<p> <p>See also <a href="#date">date</a>() and <a href="#setTime">setTime</a>().
258
259<h3 class=fn>void <a name="setTime"></a>QDateTime::setTime ( const&nbsp;<a href="qtime.html">QTime</a>&nbsp;&amp;&nbsp;time )
260</h3>
261
262<p> Sets the time part of this datetime to <em>time</em>.
263<p> <p>See also <a href="#time">time</a>() and <a href="#setDate">setDate</a>().
264
265<h3 class=fn>void <a name="setTime_t"></a>QDateTime::setTime_t ( uint&nbsp;secsSince1Jan1970UTC, <a href="qt.html#TimeSpec-enum">Qt::TimeSpec</a>&nbsp;ts )
266</h3>
267Sets the date and time to <em>ts</em> time (<a href="qt.html#TimeSpec-enum">Qt::LocalTime</a> or <a href="qt.html#TimeSpec-enum">Qt::UTC</a>) given the number of seconds that have passed since
2681970-01-01T00:00:00, Coordinated Universal Time (UTC). On systems
269that do not support timezones this function will behave as if
270local time were UTC.
271<p> On Windows, only a subset of <em>secsSince1Jan1970UTC</em> values are
272supported, as Windows starts counting from 1980.
273<p> <p>See also <a href="#toTime_t">toTime_t</a>().
274
275<h3 class=fn>void <a name="setTime_t-2"></a>QDateTime::setTime_t ( uint&nbsp;secsSince1Jan1970UTC )
276</h3>
277This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
278<p> Convenience function that sets the date and time to local time
279based on the given UTC time.
280
281<h3 class=fn><a href="qtime.html">QTime</a> <a name="time"></a>QDateTime::time () const
282</h3>
283
284<p> Returns the time part of the datetime.
285<p> <p>See also <a href="#setTime">setTime</a>() and <a href="#date">date</a>().
286
287<h3 class=fn><a href="qstring.html">QString</a> <a name="toString"></a>QDateTime::toString ( const&nbsp;<a href="qstring.html">QString</a>&nbsp;&amp;&nbsp;format ) const
288</h3>
289Returns the datetime as a string. The <em>format</em> parameter
290determines the format of the result string.
291<p> These expressions may be used for the date:
292<p> <center><table cellpadding="4" cellspacing="2" border="0">
293<tr bgcolor="#a2c511"> <th valign="top">Expression <th valign="top">Output
294<tr bgcolor="#f0f0f0"> <td valign="top">d <td valign="top">the day as number without a leading zero (1-31)
295<tr bgcolor="#d0d0d0"> <td valign="top">dd <td valign="top">the day as number with a leading zero (01-31)
296<tr bgcolor="#f0f0f0"> <td valign="top">ddd
297<td valign="top">the abbreviated localized day name (e.g. 'Mon'..'Sun').
298Uses <a href="qdate.html#shortDayName">QDate::shortDayName</a>().
299<tr bgcolor="#d0d0d0"> <td valign="top">dddd
300<td valign="top">the long localized day name (e.g. 'Monday'..'Sunday').
301Uses <a href="qdate.html#longDayName">QDate::longDayName</a>().
302<tr bgcolor="#f0f0f0"> <td valign="top">M <td valign="top">the month as number without a leading zero (1-12)
303<tr bgcolor="#d0d0d0"> <td valign="top">MM <td valign="top">the month as number with a leading zero (01-12)
304<tr bgcolor="#f0f0f0"> <td valign="top">MMM
305<td valign="top">the abbreviated localized month name (e.g. 'Jan'..'Dec').
306Uses <a href="qdate.html#shortMonthName">QDate::shortMonthName</a>().
307<tr bgcolor="#d0d0d0"> <td valign="top">MMMM
308<td valign="top">the long localized month name (e.g. 'January'..'December').
309Uses <a href="qdate.html#longMonthName">QDate::longMonthName</a>().
310<tr bgcolor="#f0f0f0"> <td valign="top">yy <td valign="top">the year as two digit number (00-99)
311<tr bgcolor="#d0d0d0"> <td valign="top">yyyy <td valign="top">the year as four digit number (1752-8000)
312</table></center>
313<p> These expressions may be used for the time:
314<p> <center><table cellpadding="4" cellspacing="2" border="0">
315<tr bgcolor="#a2c511"> <th valign="top">Expression <th valign="top">Output
316<tr bgcolor="#f0f0f0"> <td valign="top">h
317<td valign="top">the hour without a leading zero (0..23 or 1..12 if AM/PM display)
318<tr bgcolor="#d0d0d0"> <td valign="top">hh
319<td valign="top">the hour with a leading zero (00..23 or 01..12 if AM/PM display)
320<tr bgcolor="#f0f0f0"> <td valign="top">m <td valign="top">the minute without a leading zero (0..59)
321<tr bgcolor="#d0d0d0"> <td valign="top">mm <td valign="top">the minute with a leading zero (00..59)
322<tr bgcolor="#f0f0f0"> <td valign="top">s <td valign="top">the second whithout a leading zero (0..59)
323<tr bgcolor="#d0d0d0"> <td valign="top">ss <td valign="top">the second whith a leading zero (00..59)
324<tr bgcolor="#f0f0f0"> <td valign="top">z <td valign="top">the milliseconds without leading zeroes (0..999)
325<tr bgcolor="#d0d0d0"> <td valign="top">zzz <td valign="top">the milliseconds with leading zeroes (000..999)
326<tr bgcolor="#f0f0f0"> <td valign="top">AP
327<td valign="top">use AM/PM display. <em>AP</em> will be replaced by either "AM" or "PM".
328<tr bgcolor="#d0d0d0"> <td valign="top">ap
329<td valign="top">use am/pm display. <em>ap</em> will be replaced by either "am" or "pm".
330</table></center>
331<p> All other input characters will be ignored.
332<p> Example format strings (assumed that the QDateTime is
33321<small><sup>st</sup></small> May 2001 14:13:09)
334<p> <center><table cellpadding="4" cellspacing="2" border="0">
335<tr bgcolor="#a2c511"> <th valign="top">Format <th valign="top">Result
336<tr bgcolor="#f0f0f0"> <td valign="top">dd.MM.yyyy <td valign="top" colspan="1" rowspan="1"> 21.05.2001
337<tr bgcolor="#d0d0d0"> <td valign="top">ddd MMMM d yy <td valign="top" colspan="1" rowspan="1"> Tue May 21 01
338<tr bgcolor="#f0f0f0"> <td valign="top">hh:mm:ss.zzz <td valign="top" colspan="1" rowspan="1"> 14:13:09.042
339<tr bgcolor="#d0d0d0"> <td valign="top">h:m:s ap <td valign="top" colspan="1" rowspan="1"> 2:13:9 pm
340</table></center>
341<p> If the datetime is an invalid datetime, then <a href="qstring.html#QString-null">QString::null</a> will be returned.
342<p> <p>See also <a href="qdate.html#toString">QDate::toString</a>() and <a href="qtime.html#toString">QTime::toString</a>().
343
344<h3 class=fn><a href="qstring.html">QString</a> <a name="toString-2"></a>QDateTime::toString ( <a href="qt.html#DateFormat-enum">Qt::DateFormat</a>&nbsp;f = Qt::TextDate ) const
345</h3>
346This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
347<p> Returns the datetime as a string. The <em>f</em> parameter determines
348the format of the string.
349<p> If <em>f</em> is <a href="qt.html#DateFormat-enum">Qt::TextDate</a>, the string format is "Wed May 20
35003:40:13 1998" (using <a href="qdate.html#shortDayName">QDate::shortDayName</a>(), <a href="qdate.html#shortMonthName">QDate::shortMonthName</a>(),
351and <a href="qtime.html#toString">QTime::toString</a>() to generate the string, so the day and month
352names will have localized names).
353<p> If <em>f</em> is <a href="qt.html#DateFormat-enum">Qt::ISODate</a>, the string format corresponds to the
354ISO 8601 extended specification for representations of dates and
355times, which is YYYY-MM-DDTHH:MM:SS.
356<p> If <em>f</em> is <a href="qt.html#DateFormat-enum">Qt::LocalDate</a>, the string format depends on the
357locale settings of the system.
358<p> If the format <em>f</em> is invalid or the datetime is invalid, <a href="#toString">toString</a>()
359returns a null string.
360<p> <p>See also <a href="qdate.html#toString">QDate::toString</a>() and <a href="qtime.html#toString">QTime::toString</a>().
361
362<h3 class=fn>uint <a name="toTime_t"></a>QDateTime::toTime_t () const
363</h3>
364Returns the datetime as the number of seconds that have passed
365since 1970-01-01T00:00:00, Coordinated Universal Time (UTC).
366<p> On systems that do not support timezones, this function will
367behave as if local time were UTC.
368<p> <p>See also <a href="#setTime_t">setTime_t</a>().
369
370<hr><h2>Related Functions</h2>
371<h3 class=fn><a href="qdatastream.html">QDataStream</a>&nbsp;&amp; <a name="operator-lt-lt"></a>operator&lt;&lt; ( <a href="qdatastream.html">QDataStream</a>&nbsp;&amp;&nbsp;s, const&nbsp;<a href="qdatetime.html">QDateTime</a>&nbsp;&amp;&nbsp;dt )
372</h3>
373
374<p> Writes the datetime <em>dt</em> to the stream <em>s</em>.
375<p> <p>See also <a href="datastreamformat.html">Format of the QDataStream operators</a>.
376
377<h3 class=fn><a href="qdatastream.html">QDataStream</a>&nbsp;&amp; <a name="operator-gt-gt"></a>operator&gt;&gt; ( <a href="qdatastream.html">QDataStream</a>&nbsp;&amp;&nbsp;s, <a href="qdatetime.html">QDateTime</a>&nbsp;&amp;&nbsp;dt )
378</h3>
379
380<p> Reads a datetime from the stream <em>s</em> into <em>dt</em>.
381<p> <p>See also <a href="datastreamformat.html">Format of the QDataStream operators</a>.
382
383<!-- eof -->
384<hr><p>
385This file is part of the <a href="index.html">Qt toolkit</a>.
386Copyright &copy; 1995-2007
387<a href="http://www.trolltech.com/">Trolltech</a>. All Rights Reserved.<p><address><hr><div align=center>
388<table width=100% cellspacing=0 border=0><tr>
389<td>Copyright &copy; 2007
390<a href="troll.html">Trolltech</a><td align=center><a href="trademarks.html">Trademarks</a>
391<td align=right><div align=right>Qt 3.3.8</div>
392</table></div></address></body>
393</html>
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