Web服务允许此元素为空.但是,因为它被定义为Int64,当我在Delphi中使用Web服务而不为其设置值时,它默认为0,因为它是Int64.但我需要它为空,Web服务不接受值0(0被定义为无效并由Web服务返回错误).
如果类型是Int64,我如何传递空值？
解决方法
<E06_14></E06_14>
可能有特殊意义,例如“未知”年龄.
在这种情况下,真正的问题是如何使字段在Delphi端可用.
从J.M. Babet的this post开始：
Support for ‘nil’ has been an ongoing issue. Several built-in types of
Delphi are not nullable. So we opted to use a class for these cases
(not elegant but it works). So with the latest update for Delphi 2007
I have added several TXSxxxx types to help with this. Basically:
TXSBoolean,TXSInteger,TXSLong,etc. TXSString was already there but
it was not registered. Now it is. When importing a WSDL you must
enable the Use ‘TXSString for simple nillable types’ option to make
the importer switch to TXSxxxx types. On the command line it is the
“-0z+” option.
DocWiki for the Import WSDL Wizard还显示了与可支付元素相关的两个选项：
Process nillable and optional elements – Check this option to make the WSDL importer generate relevant information about optional
and nillable properties. This information is used by the SOAP runtime
to allow certain properties be nil.- @H_502_48@
Use TXSString for simple nillable types – The WSDL standard allows simple types to be nil,in Delphi or NULL,in C++,while Delphi and C++ do not allow that. Check this option to make the WSDL importer overcome this limitation by using instances of wrapper classes.
