解决libxml2不支持中文的问题

使用libxml2处理xml文件时，默认加载是使用utf-8编码，所以在修改和保存为GB2312编码时，需要将数据转换为utf-8编码，然后再进行修改和保存！

转换使用iconv，以下是转换代码

char * ConvertEnc( char *encFrom, char *encTo, const char * in)
{

static char bufin[1024], bufout[1024], *sin, *sout;
int mode, lenin, lenout, ret, nline;
iconv_t c_pt;

if ((c_pt = iconv_open(encTo, encFrom)) == (iconv_t)-1)
{
printf("iconv_open false: %s ==> %s\n", encFrom, encTo);
return NULL;
}
iconv(c_pt, NULL, NULL, NULL, NULL);

lenin = strlen(in) + 1;
lenout = 1024;
sin = (char *)in;
sout = bufout;
ret = iconv(c_pt, &sin, (size_t *)&lenin, &sout, (size_t *)&lenout);

if (ret == -1)
{
return NULL;

}

iconv_close(c_pt);

return bufout;
}

以下是实例

test.xml

1<parent>测试</parent>

** 读取代码 **

int main(void)
{
xmlDocPtr doc = NULL;
xmlNodePtr cur = NULL;

doc = xmlParseFile("test.xml");
cur = xmlDocGetRootElement(doc);
printf("%s\n", Convert("utf-8", "gb2312", (char *)xmlNodeGetContent(cur)));
}
** 修改、保存代码 **

** test2.xml **

 1<story>
 2<storyinfo>
 3<author>John Fleck</author>
 4<datewritten>June 2, 2002</datewritten>
 5<keyword>我来也 example keyword</keyword>   
 6&lt;书目&gt; C++ <!--书目-->   
 7&lt;测试&gt; test <!--测试-->
 8</storyinfo>
 9<body>
10<headline>This is the headline</headline>
11<para>This is the body text.</para>
12</body>
13</story>

** xmlDocPtr
parseDoc(char *docname, char *uri) {

xmlDocPtr doc;
xmlNodePtr cur;
xmlNodePtr newnode;
xmlAttrPtr newattr;

doc = xmlParseFile(docname);

if (doc == NULL ) {
fprintf(stderr,"Document not parsed successfully. \n");
return (NULL);
}

cur = xmlDocGetRootElement(doc);

if (cur == NULL) {
fprintf(stderr,"empty document\n");
xmlFreeDoc(doc);
return (NULL);
}

if (xmlStrcmp(cur->name, (const xmlChar *) "story")) {
fprintf(stderr,"document of the wrong type, root node != story");
xmlFreeDoc(doc);
return (NULL);
}

newnode = xmlNewTextChild (cur, NULL, (xmlChar *)"reference", NULL);
newattr = xmlNewProp (newnode, (xmlChar *)"uri", (xmlChar *)uri);
return(doc);
}

int main(int argc, char ** argv )
{
int options = 0;
xmlDocPtr doc = NULL;
char * output = NULL;
char * szNode = NULL;
int ret = 0;

xmlAddEncodingAlias("UTF-8", "DVEnc");
xmlKeepBlanksDefault(0);
defaultEntityLoader = xmlGetExternalEntityLoader();
xmlSetExternalEntityLoader(xmllintExternalEntityLoader);
xmlLineNumbersDefault(1);

szNode = Convert("gb2312", "utf-8", "测试" );
doc = parseDoc( argv[2], szNode);

ret = xmlSaveFormatFileEnc(output ? output : "-", doc, argv[1], 1);
if (ret < 0)
{
fprintf(stderr, "failed save to %s\n",
output ? output : "-");
}
return 0;
}

执行

xmlout gb2312 test2.xml

结果

 1<story>
 2<storyinfo>
 3<author>John Fleck</author>
 4<datewritten>June 2, 2002</datewritten>
 5<keyword>我来也 example keyword</keyword>   
 6&lt;书目&gt; C++ <!--书目-->   
 7&lt;测试&gt; test <!--测试-->
 8</storyinfo>
 9<body>
10<headline>This is the headline</headline>
11<para>This is the body text.</para>
12</body>
13<reference uri="测试"></reference>
14</story>