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<TITLE>RE: [Seaside] How to do validation such as for money (with a currencyclass) in WAEditDialog subclasses?</TITLE>
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<P><FONT SIZE=2>> On Fri, 29 Oct 2004 21:44:52 +0800, Yar Hwee Boon </FONT>
<BR><FONT SIZE=2>> <hboon@motionobj.com> </FONT>
<BR><FONT SIZE=2>> wrote:</FONT>
<BR><FONT SIZE=2>> </FONT>
<BR><FONT SIZE=2>> > However, how do I validate input which is non-digit? The #amount:</FONT>
<BR><FONT SIZE=2>> </FONT>
<BR><FONT SIZE=2>> Just to clarify, I mean how do I valiate short of using Javascript.</FONT>
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<P><FONT SIZE=2>I think your should not update your domain objects directly.</FONT>
<BR><FONT SIZE=2>I would use the command pattern, i.e. the model of your</FONT>
<BR><FONT SIZE=2>Seaside component should be a command. You would collect</FONT>
<BR><FONT SIZE=2>all the command data using the callbacks of your component</FONT>
<BR><FONT SIZE=2>Then the callback attached to the OK button would send #execute</FONT>
<BR><FONT SIZE=2>to the command object. Assuming that #execute performs the</FONT>
<BR><FONT SIZE=2>validation, you would get an exception describing the error(s).</FONT>
<BR><FONT SIZE=2>On the next rendering, you would alter the display to using</FONT>
<BR><FONT SIZE=2>the error description(s).</FONT>
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<P><FONT SIZE=2>Did you have a look to Mewa ? It does validation using another</FONT>
<BR><FONT SIZE=2>technique where you have a meta-wrapper for every aspects of</FONT>
<BR><FONT SIZE=2>the domain object. But again the domain object is not updated</FONT>
<BR><FONT SIZE=2>directly.</FONT>
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<P><FONT SIZE=2>Hope this helps,</FONT>
<BR><FONT SIZE=2>Michel.</FONT>
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