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<td align="left"><A href="ValueRead_Usage.html" style="TEXT-DECORATION: none"><h3>Usage</h3></A>
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<td colspan="3"><h1>SAValueRead::asDouble</h1></td>
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<p><font face="Arial"><b> double asDouble( )
const;<BR> </b></font><STRONG><FONT face=Arial>throw
(SAException);</FONT></STRONG></p>
<p><STRONG><FONT
face=Arial>operator double( ) const;<BR
>throw (SAException);</FONT></STRONG></p>
<p><STRONG>asDouble</STRONG>
method
returns the value of current object (usually
<A href="Field.html">SAField</A>
or <A href="Param.html">SAParam</A>
object) as <STRONG>double</STRONG>
data.
</p>
<p><STRONG>operator
double()</STRONG> substitute <STRONG>asDouble</STRONG> method to provide quick access for object's
value.</p>
<h3>Remarks</h3>
<P>If the value of current object is NULL,
<STRONG>asDouble</STRONG> method returns
<STRONG>0</STRONG>. Use <FONT color=mediumblue face=""><A
href="ValueRead_isNull.html">SAValueRead::isNull</A></FONT>
method
to make sure if the value is NULL or not.</P>
<P>If the value's type of current object is
double (<STRONG>SA_dtDouble</STRONG>),
<STRONG>asDouble</STRONG> method returns the original value with no
conversion.</P>
<P>If the value's type of current object is
bool (<STRONG>SA_dtBool</STRONG> ),
short (<STRONG>SA_dtShort</STRONG> ), long
(<STRONG>SA_dtLong</STRONG>) or numeric
(<STRONG>SA_dtNumeric</STRONG>), <STRONG>asDouble</STRONG> method converts it to double (
<STRONG>SA_dtDouble</STRONG>
) data type.</P>
<P>If the value's type of current object is
string (<STRONG>SA_dtString</STRONG>),
<STRONG>asDouble</STRONG> method tries to convert it to
<STRONG>double</STRONG>
value. If the
conversion is possible and correct, <STRONG>asDouble</STRONG> returns
<STRONG>SA_dtDouble</STRONG> value. If conversion is
incorrect <STRONG>asDouble</STRONG> method
throws an exception.</P>
<P> If the value's type of current
object is
<STRONG>SA_dtDateTime</STRONG>,
<STRONG>asDouble</STRONG> method converts it to standard
<STRONG>double</STRONG> representation. Days are
represented by whole number increments starting with 30 December
1899, midnight as time zero. Hour values are expressed as the
absolute value of the fractional part of the number. See <A
href="DateTime_operator_double.html">SADateTime::operator
double()</A>
for more detailes.</P>
<P>If the value's type of current object is any data
type except the described above, the result is undefined and debug version
asserts.</P>
<P>Use <A href="ValueRead_DataType.html" >SAValueRead::DataType</A> method to get the
value's type of <STRONG>SAValueRead</STRONG>
object.</P>
<h3>Server specific notes</h3>
<P>No specific information.</P>
<h3> See also</h3>
<P><A href="ValueRead_isNull.html">isNull</A>, <A
href="ValueRead_asBool.html">asBool</A>,
<A href="ValueRead_asShort.html">asShort</A>, <A
href="ValueRead_asLong.html">asLong</A>, <A
href="ValueRead_asNumeric.html">asNumeric</A>, <A
href="ValueRead_asDateTime.html">asDateTime</A>, <A
href="ValueRead_asString.html">asString</A>, <A
href="ValueRead_asBytes.html">asBytes</A>, <A
href="ValueRead_asLongBinary.html">asLongBinary</A>, <A
href="ValueRead_asLongChar.html">asLongChar</A>, <A
href="ValueRead_asBLob.html">asBLob</A>, <A
href="ValueRead_asCLob.html">asCLob</A>, <A
href="ValueRead_asCursor.html">asCursor</A>, <A
href="ValueRead_DataType.html">DataType</A>
</P>
<P><A href="Enums.html#SADataType_t" >SADataType_t</A> </P>
<P><A href="../HowTo/errors.html" >Error handling</A></P>
<h3>Problems and Questions</h3>
<p> If
you haven't found the answer to your questions or
have some problems on using the Library, please, send e-mail to <A href="mailto:howto@sqlapi.com">howto@sqlapi.com</A>.
</p>
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