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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 align="left"><A href="ValueRead.html" style="TEXT-DECORATION: none"><h3>Class Members</h3></A>
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<td align="left"><A href="ValueRead_Examples.html" style="TEXT-DECORATION: none"><h3>Examples</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>) or long
(<STRONG>SA_dtLong</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 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_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 don't find the answer to you 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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