获取libxml2的内容

Question

I'm trying to use libxml2's function xmlNodeGetContent to acess content from an xml file, but for some reason content within self-closing tabs can't be read.

void parseRow (xmlDocPtr doc, xmlNodePtr cur) {

    xmlChar *key;
    cur = cur-> xmlChildrenNode;
    while (cur != NULL) {
        if ((!xmlStrcmp(cur->name, (const xmlChar *)"row"))) {
            key = xmlNodeGetContent( cur->children );
            printf("keyword: %s\n", (char*)key);
            xmlFree(key);
        }
        cur = cur -> next;
    }
    return;
}

I'm using this sample xml file with both types of tabs and the first row tab can be read while the second one returns (null);

<?xml version="1.0"?>
<story>
  <storyinfo>
    <author>John Fleck</author>
    <datewritten>June 2, 2002</datewritten>
    <row> Id="1" UserId="1" </row>
    <row Id="1" UserId="1" />
    <keyword>Id="hello"</keyword>
  </storyinfo>
</story>

Answer 1

The second row element is empty, it has no content, only attributes.

<tag>non-empty content</tag>
<tag content="attribute value"/>

Without any schema, it's impossible for the framework to know what type the second tag element is and it can't have a default value defined for it, and it can't derive a type, therefore it has no content. It does have a content attribute however, but you access attributes using different methods in most of the frameworks I am aware of.

Answer 2

如果要获取属性值，请使用xmlGetProp。