如何处理错误 C2440 “<function-style-cast>”: 无法从“_Ty”转换为“LPoint”

在vs2003没有报错 升级到vs2017就报错  






--
FROM 123.113.225.*

/********************************************************************
    created:    2005/05/13
    created:    13:5:2005   15:45
    filename:     include\sysutils\variant.h
    file path:    include\sysutils
    author:        陈闽峰
    
    purpose:    定义一个可以代表类型动态改变的值。
*********************************************************************
Release Note  :


*********************************************************************/

#pragma once
#include "afxdisp.h"
#include "types.h"
#include "string.h"
#include "datetime.h"
#include "ImageUID.h"
/*
* VARENUM usage key,
*
* * [V] - may appear in a LVariant
* * [T] - may appear in a TYPEDESC
* * [P] - may appear in an OLE property set
* * [S] - may appear in a Safe Array
*
*
*  VT_EMPTY            [V]   [P]     nothing
*  VT_NULL             [V]   [P]     SQL style Null
*  VT_I2               [V][T][P][S]  2 byte signed int
*  VT_I4               [V][T][P][S]  4 byte signed int
*  VT_R4               [V][T][P][S]  4 byte real
*  VT_R8               [V][T][P][S]  8 byte real
*  VT_CY               [V][T][P][S]  currency
*  VT_DATE             [V][T][P][S]  date
*  VT_BSTR             [V][T][P][S]  OLE Automation string
*  VT_DISPATCH         [V][T]   [S]  IDispatch *
*  VT_ERROR            [V][T][P][S]  SCODE
*  VT_BOOL             [V][T][P][S]  True=-1, False=0
*  VT_VARIANT          [V][T][P][S]  VARIANT *
*  VT_UNKNOWN          [V][T]   [S]  IUnknown *
*  VT_DECIMAL          [V][T]   [S]  16 byte fixed point
*  VT_RECORD           [V]   [P][S]  user defined type
*  VT_I1               [V][T][P][s]  signed char
*  VT_UI1              [V][T][P][S]  unsigned char
*  VT_UI2              [V][T][P][S]  unsigned short
*  VT_UI4              [V][T][P][S]  unsigned long
*  VT_I8                  [T][P]     signed 64-bit int
*  VT_UI8                 [T][P]     unsigned 64-bit int
*  VT_INT              [V][T][P][S]  signed machine int
*  VT_UINT             [V][T]   [S]  unsigned machine int
*  VT_INT_PTR             [T]        signed machine register size width
*  VT_UINT_PTR            [T]        unsigned machine register size width
*  VT_VOID                [T]        C style void
*  VT_HRESULT             [T]        Standard return type
*  VT_PTR                 [T]        pointer type
*  VT_SAFEARRAY           [T]        (use VT_ARRAY in VARIANT)
*  VT_CARRAY              [T]        C style array
*  VT_USERDEFINED         [T]        user defined type
*  VT_LPSTR               [T][P]     null terminated string
*  VT_LPWSTR              [T][P]     wide null terminated string
*  VT_FILETIME               [P]     FILETIME
*  VT_BLOB                   [P]     Length prefixed bytes
*  VT_STREAM                 [P]     Name of the stream follows
*  VT_STORAGE                [P]     Name of the storage follows
*  VT_STREAMED_OBJECT        [P]     Stream contains an object
*  VT_STORED_OBJECT          [P]     Storage contains an object
*  VT_VERSIONED_STREAM       [P]     Stream with a GUID version
*  VT_BLOB_OBJECT            [P]     Blob contains an object
*  VT_CF                     [P]     Clipboard format
*  VT_CLSID                  [P]     A Class ID
*  VT_VECTOR                 [P]     simple counted array
*  VT_ARRAY            [V]           SAFEARRAY*
*  VT_BYREF            [V]           void* for local use
*  VT_BSTR_BLOB                      Reserved for system use
*  VT_RECT             [V]
*  VT_POINT            [V]
*  VT_SIZE             [V]
*/
const VARTYPE VT_RECT        = 0x8001;
const VARTYPE VT_POINT        = 0x8002;
const VARTYPE VT_SIZE        = 0x8003;
const VARTYPE VT_IMAGEUID    = 0x8004;
//!\class LVariant
//!\brief LVariant类型能代表类型动态改变的值。
//!任意其他类型的一个变量静态地被约束为那个类型时，LVariant类型的一个变量可以在运行期
//!认为是不同类项的值。最常用时，在实际类型在编译时改变或未知时使用Lvariant类型。
class AFX_EXT_CLASS LVariant : public COleVariant
{
public:
    LVariant();
    LVariant(const VARIANT& varSrc);
    LVariant(const LVariant& varSrc);
    LVariant(const LDateTime& timeSrc);
    LVariant(const AnsiString& src);
    LVariant(const WideString& src);
    LVariant(const COleCurrency& curSrc);
    LVariant(const CByteArray& arrSrc);
    LVariant(const CLongBinary& lbSrc);
    LVariant(const RECT &rect);
    LVariant(const LRect &Rect);
    LVariant(const POINT &point);
    LVariant(const LPoint &Point);
    LVariant(const SIZE &size);
    LVariant(const LSize &size);
    LVariant(const LImageUID &UID);

    LVariant(LPCITEMIDLIST pidl);
    LVariant(LPCVARIANT pSrc);
    LVariant(wchar_t* lpszSrc);
    LVariant(char* lpszSrc);
    LVariant(short* src);
    LVariant(int* src);
    LVariant(long* src);
    LVariant(__int64 *src);
    LVariant(float* src);
    LVariant(double* src);
    LVariant(BYTE* src);

    LVariant(float fltSrc);
    LVariant(double dblSrc);
    LVariant(bool src);
    LVariant(BYTE nSrc);
    LVariant(short nSrc);
    LVariant(int src);
    LVariant(long lSrc);
    LVariant(__int64 src);
    LVariant(unsigned short src);
    LVariant(unsigned int src);
    LVariant(unsigned long src);
    LVariant(unsigned __int64 src);

    ~LVariant();

    bool IsArray() const;
    bool IsEmpty() const;
    bool IsNull() const;
    VARTYPE Type() const;
    LImageUID *ImageUID();
    static void StringToVrArray(AnsiString &src,std::vector<LVariant> &dest);
    static void VrArrayToString(std::vector<LVariant> &src,AnsiString &dest);

    LVariant& operator =(const WideString& src);
    LVariant& operator =(const AnsiString& src);
    LVariant& operator =(const LDateTime& src);
    LVariant& operator =(const LRect &Rect);
    LVariant& operator =(const LPoint &Point);
    LVariant& operator =(const LSize &size);
    LVariant& operator =(const LImageUID &UID);
    LVariant& operator =(bool);
    LVariant& operator =(__int64);
    LVariant& operator =(unsigned int);
    LVariant& operator =(unsigned short);
    LVariant& operator =(unsigned long);
    LVariant& operator =(unsigned __int64);
    LVariant& operator =(char* src);
    LVariant& operator =(BYTE* src);
    LVariant& operator =(int* src);
    LVariant& operator =(long* src);
    LVariant& operator =(float* src);
    LVariant& operator =(double* src);
    operator AnsiString() const;
    operator LDateTime() const;
    operator bool() const;
    
    operator LRect();
    operator LPoint();
    operator LSize();
    operator LImageUID();
    operator BYTE() const;
    operator BYTE*();
    operator char() const;
    operator double() const;
    operator double*();
    operator float() const;
    operator float*();
    operator int() const;
    operator int*();
    operator short() const;
    operator short*();
    operator long() const;
    operator long*();
    operator unsigned int() const;
    operator unsigned int*();
    operator unsigned short() const;
    operator unsigned short*();
    operator unsigned long() const;
    operator unsigned long*();

private:
    union{
        RECT FRect;
        POINT FPoint;
        SIZE FSize;
    };
    LImageUID FUID;
    VARTYPE FType;
};
// 不胜赐教 谢谢
【 在 KillnCov 的大作中提到: 】
: 你把LVar的完整头文件发出来
--
FROM 123.113.225.*

【 在 foliver 的大作中提到: 】
: 我模拟了一下你的代码，再我的VS2022上没有任何问题
: class LPoint
: {
: ...................
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修改:mazheng75 FROM 123.113.225.*
FROM 123.113.225.*