HRESULT和VARIANT_BOOL从IXMLDOMDocument方法返回值 [英] HRESULTs and VARIANT_BOOL return values from IXMLDOMDocument methods

问题描述

我一直在使用以下方法:

I have been using the following methods:

IXMLDOMDocument.CreateInstance

IXMLDOMDocument.load

我有很多麻烦检查失败的返回值. CreateInstance似乎返回HRESULT，而加载似乎返回VARIANT_BOOL.

这些重新运行类型之间是否存在一致性，或者是否存在任何逻辑?为什么每种情况下的返回类型都是HRESULT或VARIANT_BOOL?我仍然不了解HRESULTS是什么以及何时使用它们-在这个问题上似乎很少.有人可以指点我吗?

非常感谢

I have had a lot of bother checking the return values for failure. CreateInstance seems to return an HRESULT and load seems to return a VARIANT_BOOL.

Is there any coherency between these retrun types or any logic o why an HRESULT or VARIANT_BOOL is the return type in each case? I still don''t understand what HRESULTS are and when they are used - there seems to be very little on the subject. Can anyone point me at anything please?

Many thanks

推荐答案

HRESULT提供了操作的详细状态(例如，不支持接口).但是VARIANT_BOOL只是告诉您是对还是错.

http://msdn.microsoft.com/en-us/library/bb401631.aspx [ ^ ]

HRESULT provides detailed status of the operation (e.g. Interface not supported). But VARIANT_BOOL just tells true or false.

http://msdn.microsoft.com/en-us/library/bb401631.aspx[^]

这篇关于HRESULT和VARIANT_BOOL从IXMLDOMDocument方法返回值的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！