C++获取字符串中的某个子串

string FindField(const char* buf, const char* start, const char *end ,size_t bufSize) {
    if(bufSize <=0 ){
        bufSize = strlen(buf);
    }
    const char *msg_start = buf, *msg_end = buf + bufSize;
    size_t len = 0;
    if (start != NULL) {
        len = strlen(start);
        msg_start = strstr(buf, start);
    }
    if (msg_start == NULL) {
        return "";
    }
    msg_start += len;
    if (end != NULL) {
        msg_end = strstr(msg_start, end);
        if (msg_end == NULL) {
            return "";
        }
    }
    return string(msg_start, msg_end);
}

来源：ZLmediakit

 

“fnsvvavfdtgwegrgwwwwwwwwwwwwwwwww_asasasas_a” 查找w_到 _a之间的字符串；也就是asasasas

用于字符串解析，文件名解析等