对C++ XML解析器TinyXML中关于‘&’字符操作的修改

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我是靠谱客的博主着急路灯，最近开发中收集的这篇文章主要介绍对C++ XML解析器TinyXML中关于‘&’字符操作的修改，觉得挺不错的，现在分享给大家，希望可以做个参考。

概述

1.在 TinyXML中‘&’作为一个保留字符处理，当xml文档中存在单独的‘&’字符（而不是“&”），它在读取时会直接置为空字符。

解决办法：修改tinyxmlparser.cpp中 Line 528, 函数const char* TiXmlBase::GetEntity( const char* p, char* value, int* length, TiXmlEncoding encoding )实现代码中有：

// So it wasn't an entity, its unrecognized, or something like that.

*value = *p; // Don't put back the last one, since we return it!

//*length = 1; // Leave unrecognized entities - this doesn't really work.

// Just writes strange XML.

源码中将*length=1注释掉了，直接导致特殊字符‘&’ 被过滤，只需要将*length=1放开注释即可，如下：
// So it wasn't an entity, its unrecognized, or something like that.

*value = *p; // Don't put back the last one, since we return it!

*length = 1; // Leave unrecognized entities - this doesn't really work. no no no by yangw

// Just writes strange XML.

重新编译即可解决XML节点内容含有‘&’符号的过滤问题。

2.当向xml文件中写入‘&’字符（而不是“&”）时同样会有问题，TinyXML库同样会做处理，它会把‘&’替换为“&”，见文件 tinyxmlparser.cpp中

TiXmlBase::Entity TiXmlBase::entity[ TiXmlBase::NUM_ENTITY ] =
{
{ "&",  5, '&' },
{ "<",   4, '<' },
{ ">",   4, '>' },
{ """, 6, '"' },
{ "'", 6, ''' }
};

当你不需要这样的处理时可以修改 tinyxml.cpp中Line85，把

outString->append( entity[0].str, entity[0].strLength );

改为

outString->append( "&", 1);

重新编译即可解决此问题。