C++ Expat只打印标签中元素和数据的第一个字母

#include <iostream>
#include <expat.h>

void startElement(void* userData, const XML_Char* name, const XML_Char** attrs) {
    std::cout << "Start element: " << name[0] << std::endl;
}

void endElement(void* userData, const XML_Char* name) {
    std::cout << "End element: " << name[0] << std::endl;
}

void characterData(void* userData, const XML_Char* s, int len) {
    std::cout << "Character data: " << s[0] << std::endl;
}

int main() {
    XML_Parser parser = XML_ParserCreate(NULL);
    XML_SetElementHandler(parser, startElement, endElement);
    XML_SetCharacterDataHandler(parser, characterData);

    const char* xmlData = "<root><element>data</element></root>";
    XML_Parse(parser, xmlData, strlen(xmlData), true);

    XML_ParserFree(parser);
    return 0;
}