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Gambas Documentation - DateDiff
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<h1>
DateDiff
</h1>
<div class="black"><font size="-2"><b>Syntax</b></font></div>
<pre class="syntax"><u>Count</u> = <b>DateDiff (</b> <u>Date1</u> AS Date <b>,</b> <u>Date2</u> AS Date <b>,</b> <u>Period</u> AS Integer <b>)</b> AS integer</pre><p>

Returns the number of periods between two dates.
<p>
<ul>
<li><u>Date1</u> is the upper date.
<li><u>Date2</u> is the lower date.
<li><u>Period</u> is the kind of period: year, month, day, week...
<p>
</ul>

The number of periods is returned.
<p>
<u>Period</u> can be one of the following constants:
<p>
<table class="table" border="0" bordercolor="#000000" cellpadding="4" cellspacing="0">
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Constant
</th><th>
Effect
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<tt><a href="../comp/gb/gb+en">gb</a>.<a href="../comp/gb/gb/second+en">Second</a></tt>
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Returns a number of seconds.
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<tt><a href="../comp/gb/gb+en">gb</a>.<a href="../comp/gb/gb/minute+en">Minute</a></tt>
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Returns a number of minutes.
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<tt><a href="../comp/gb/gb+en">gb</a>.<a href="../comp/gb/gb/hour+en">Hour</a></tt>
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Returns a number of hours.
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<tt><a href="../comp/gb/gb+en">gb</a>.<a href="../comp/gb/gb/day+en">Day</a></tt>
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Returns a number of days.
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<tt><a href="../comp/gb/gb+en">gb</a>.<a href="../comp/gb/gb/week+en">Week</a></tt>
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Returns a number of weeks.
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<tt><a href="../comp/gb/gb+en">gb</a>.<a href="../comp/gb/gb/weekday+en">WeekDay</a></tt>
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Returns a number of week days (Saturday and Sunday are ignored).
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<tt><a href="../comp/gb/gb+en">gb</a>.<a href="../comp/gb/gb/month+en">Month</a></tt>
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Returns a number of months.
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<tt><a href="../comp/gb/gb+en">gb</a>.<a href="../comp/gb/gb/quarter+en">Quarter</a></tt>
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Returns a number of quarters.
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<tt><a href="../comp/gb/gb+en">gb</a>.<a href="../comp/gb/gb/year+en">Year</a></tt>
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Returns a number of years.
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<p>

Only entire periods are returned. The result is round down.
<div class="gray"><font size="-2"><b>Example</b></font></div>
<pre class="example">PRINT DateDiff(&quot;01/02/2005 12:55:00&quot;, &quot;01/01/2005&quot;, gb.Day)
<hr>-1</pre>
<p>
This example shows how DateDiff works internally
<div class="gray"><font size="-2"><b>Example</b></font></div>
<pre class="example">DIM date1 AS Date
DIM date2 AS Date
DIM fDiff AS Float
DIM iDiff AS Integer

date1 = Date(1964, 02, 28, 0, 29, 0)
date2 = Date(1964, 03, 01, 0, 30, 0) ' one minute more than two days
fDiff = CFloat(date2) - CFloat(date1)
iDiff = Int(fDiff * 24)
PRINT &quot;first  : &quot;; fdiff; &quot;  int:&quot;; idiff; &quot;  DateDiff:&quot;; DateDiff(date1, date2, gb.Hour)
date1 = Date(1964, 02, 28, 0, 30, 0)
date2 = Date(1964, 03, 01, 0, 29, 0) ' one minute less than two days
fDiff = CFloat(date2) - CFloat(date1)
iDiff = Int(fDiff * 24)
PRINT &quot;second : &quot;; fdiff; &quot;  int:&quot;; idiff; &quot;  DateDiff:&quot;; DateDiff(date1, date2, gb.Hour)

<hr>first  : 2.000694444403  int:48  DateDiff:48
second : 1.999305555597  int:47  DateDiff:47</pre>
<p>
<hr><b>See also</b><br>
<a href="../cat/time+en">Date &amp; Time Functions</a>&nbsp;

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