Question

我需要转换此结构

dt[, age := decimal_date(disease.date) - decimal_date(dob)]

到typedef struct zidrecord2 { char version; char flags; char filler1; char filler2; unsigned char identifier[IDENTIFIER_LEN]; unsigned char rs1Interval[TIME_LENGTH]; unsigned char rs1Data[RS_LENGTH]; unsigned char rs2Interval[TIME_LENGTH]; unsigned char rs2Data[RS_LENGTH]; unsigned char mitmKey[RS_LENGTH]; }或另一个允许再次回滚到该对象的对象我试试这个：

char *

但是我收到以下错误：

zidrecord2_t* amostra =  zidRecord->getRecordData();

const char *recordData = reinterpret_cast<const char*>(zidRecord->getRecordData());
    __android_log_print(ANDROID_LOG_INFO, "MyTag", "The value is %s",recordData);
    amostra = reinterpret_cast<zidrecord2_t*>(recordData);
    __android_log_print(ANDROID_LOG_INFO, "MyTag", "The value is %s",recordData);

我怎样才能传递这个问题？或以另一种方式实施？

Answer 1

amostra = reinterpret_cast<const zidrecord2_t*>(recordData);

从const投射到const。

如果你想展开const，请从头开始使用非const指针。

Answer 2

您可以添加用户定义的转换运算符：

因此，您的代码可能如下所示：

typedef struct zidrecord2 {
    char version;  
    char flags;     
    char filler1;   
    char filler2;   
    unsigned char identifier[IDENTIFIER_LEN]; 
    unsigned char rs1Interval[TIME_LENGTH];   
    unsigned char rs1Data[RS_LENGTH];         
    unsigned char rs2Interval[TIME_LENGTH]; 
    unsigned char rs2Data[RS_LENGTH];        
    unsigned char mitmKey[RS_LENGTH];

    operator char*() const { return ConvertToCharPointerHere();
}

C ++ - 将struct转换为char

2 个答案: