在C程序中使用libxml/xpath查找和替换XML文件中的属性

#include <libxml/parser.h>
#include <libxml/xpath.h>

xmlDocPtr doc = xmlParseFile("example.xml");
if (doc == NULL) {
    // 处理加载失败的情况
}

xmlXPathContextPtr xpathCtx = xmlXPathNewContext(doc);
if (xpathCtx == NULL) {
    // 处理创建失败的情况
}

const xmlChar* xpathExpr = (const xmlChar*)"/root/element[@attribute='value']";

xmlXPathObjectPtr xpathObj = xmlXPathEvalExpression(xpathExpr, xpathCtx);
if (xpathObj == NULL) {
    // 处理查询失败的情况
}

xmlNodeSetPtr nodes = xpathObj->nodesetval;
for (int i = 0; i < nodes->nodeNr; ++i) {
    xmlNodePtr node = nodes->nodeTab[i];
    xmlSetProp(node, (const xmlChar*)"attribute", (const xmlChar*)"new_value");
}

xmlSaveFormatFile("example.xml", doc, 1);

xmlXPathFreeObject(xpathObj);
xmlXPathFreeContext(xpathCtx);
xmlFreeDoc(doc);