cvariant.h

很好用的数据库连接组件

#ifndef CVARIANT_H
#define CVARIANT_H
#include <string>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>

#include "CDate.h"
#include "CSqlShared.h"

# if defined(_REENTRANT)
#include "mymutex.h"
#include "mymutexpool_p.h"
# endif
using namespace std;
class CVariant
{
public:

  enum Type//定义支持的数据类型
  {
    Invalid = 0,//无效类型
    Bool = 1,//bool类型
    UShort = 2,//无符号短整数
    Short = 3,//短整数
    UInt = 4,//无符号整数
    Int = 5,//整数
    ULong = 6,//无符号长整数
    Long = 7,//长整数
    Float = 8,//单精度浮点数
    Double = 9,//双精度浮点数
    Pchar = 10 ,//字符串指针
    mydate = 11 //时间类
  };

    CVariant ();//构造空的CVariant类型
    CVariant (const CVariant &);//拷贝构造CVariant类型
    CVariant (bool val);//以布尔型构造CVariant类型
    CVariant (unsigned short val);//以无符号短整数构造CVariant类型
    CVariant (short val);//以短整数构造CVariant类型
    CVariant (unsigned int val);//以无符号整数构造CVariant类型
    CVariant (int val);//以整数构造CVariant类型
    CVariant (unsigned long val);//以无符号长整数构造CVariant类型
    CVariant (long val);//以长整数构造CVariant类型
    CVariant (float val);//以单精度浮点数构造CVariant类型
    CVariant (double val);//以双精度浮点数构造CVariant类型
    CVariant (const char *val);//以字符串构造CVariant类型
    CVariant (const CDate_T& val);//以CDate_T类构造CVariant类型
   ~CVariant ();//析构CVariant类型


  CVariant & operator = (const CVariant &);//支持=运算符
  bool operator == (const CVariant &) const  ;//支持==运算符
  bool operator != (const CVariant &) const ;//支持！=运算符
  operator bool(void) {
  	return this->toBool();
  }
  operator unsigned short(void) {
  	return this->toUShort();
  }
  operator short(void) {
  	return this->toShort();
  }
  operator unsigned int(void) {
  	return this->toUInt();
  }
  operator int(void) {
  	return this->toInt();
  }
  operator unsigned long(void) {
  	return this->toULong();
  }
  operator long(void) {
  	return this->toLong();
  }
  operator float(void) {
  	return this->toFloat();
  }
  operator double(void) {
  	return this->toDouble();
  }
  operator const char*(void) {
  	return this->toPchar();
  }
  operator CDate_T(void) {
  	return this->toMyDate();
  }


  inline Type type () const;//返回当前类型
  const char *typeName () const;//返回当前类型名

  bool canCast (Type) const;//当前类型能否转化为参数中类型
  bool cast (Type);//将当前类型转化为参数中类型

  inline bool isValid () const;//是否是无效类型
  bool isNull () const;//是否是空值

  void clear ();//清除数据

  bool toBool () const;//将当前值转化为bool型返回，但不改变当前类型
  unsigned short toUShort (bool * ok = NULL) const;//将当前值转化为unsigned short型返回，但不改变当前类型,结果放入ok
  short toShort (bool * ok = NULL) const;//将当前值转化为short型返回，但不改变当前类型,结果放入ok
  unsigned int toUInt (bool * ok = NULL) const;//将当前值转化为unsigned int型返回，但不改变当前类型,结果放入ok
  int toInt (bool * ok = NULL) const;//将当前值转化为int型返回，但不改变当前类型,结果放入ok
  unsigned long  toULong (bool * ok = NULL) const;//将当前值转化为unsigned long型返回，但不改变当前类型,结果放入ok
  long  toLong (bool * ok = NULL) const;//将当前值转化为int型返回，但不改变当前类型,结果放入ok
  float toFloat (bool * ok = NULL) const;//将当前值转化为double型返回，但不改变当前类型,结果放入ok
  double toDouble (bool * ok = NULL) const;//将当前值转化为double型返回，但不改变当前类型,结果放入ok
  const char *toPchar (bool * ok = NULL) const ;//将当前值转化为const char*型返回，但不改变当前类型,结果放入ok
  CDate_T toMyDate (bool * ok = NULL) const;//将当前值转化为CDate_T型返回，但不改变当前类型,结果放入ok

  bool asBool ();//将CVariant中的内部类型及值转化为bool
  unsigned short asUShort ();//将CVariant中的内部类型及值转化为unsigned short
  short asShort ();//将CVariant中的内部类型及值转化为short
  unsigned int asUInt ();//将CVariant中的内部类型及值转化为unsigned int
  int asInt ();//将CVariant中的内部类型及值转化为int
  unsigned long asULong ();//将CVariant中的内部类型及值转化为unsigned long
  long asLong ();//将CVariant中的内部类型及值转化为long
  float asFloat ();//将CVariant中的内部类型及值转化为double
  double asDouble ();//将CVariant中的内部类型及值转化为float 
  const char *asPchar ();//将CVariant中的内部类型及值转化为const char*
  CDate_T asMyDate ();////将CVariant中的内部类型及值转化为CDate_T


  static const char *typeToName (Type typ);//返回类型对应的名字
  static Type nameToType (const char *name);//返回名字对应的类型

private:

  void detach ();//脱离对当前值的依赖，建立自己的值拷贝
  bool str_can_double (const char *pszStr) const;//字符串能否转化为double
  bool str_can_long (const char *pszStr) const;//字符串能否转化为long

  class Private:public CShared//继承自CShared的私有类
  {
  public:
    Private ();
    Private (Private *);
    ~Private ();

    void clear ();//清除数据

    Type typ;//当前值的类型
    union 
    {
      bool b;
      unsigned short us;
      short s;
      unsigned int ui;
      int i;
      unsigned long ul;
      long l;
      float f;
      double d;
      char *ptr;
      CDate_T* date;
    }
    value;//当前值
  };

// static  std::string i_temp;
  Private *d;//私有类指针
};
#endif