cannot convert from ???? to ???

2009-09-01 02:23:59 495 阅读 AI 写同款 · GEO 优化AI 选题数据监测一键分发 ›

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一遇到类型转换的问题就很头大
cannot convert from ???? to ???
大家有没有好的经验分享一下？

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codeyell-com 2009-09-01

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够雷，哈哈

songsu 2009-09-01

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我有个雷类。

// Convert.cpp: implementation of the Convert class.

//

//////////////////////////////////////////////////////////////////////



#include "stdafx.h"

#include "Convert.h"



#ifdef _DEBUG

#undef THIS_FILE

static char THIS_FILE[]=__FILE__;

#define new DEBUG_NEW

#endif



using namespace Xproer::System;



//////////////////////////////////////////////////////////////////////

// Construction/Destruction

//////////////////////////////////////////////////////////////////////



Convert::Convert()

{



}



Convert::~Convert()

{



}



int Convert::ToInt(wchar_t* v)

{

	string cs = ToString(v);

	

	return ToInt(cs);

}



int Convert::ToInt(const char* v)

{

	return atoi(v);

}



int Convert::ToInt(char* v)

{

	return atoi(v);

}



/*

 *	2008-12-15	将 v.GetBuffer 转换改为 (LPCTSTR)

 */

int Convert::ToInt(const CString& v)

{	

	return atoi((LPCTSTR)v);

}



int Convert::ToInt(const string& v)

{

	return ToInt(v.c_str());

}



int Convert::ToInt(const wstring& v)

{

	wchar_t* wcs = const_cast<wchar_t*>(v.c_str());

	return ToInt(wcs);

}



/*

 *	To Int64	

 */

__int64 Convert::ToInt64(char* v)

{

	return _atoi64(v);

}



__int64 Convert::ToInt64(const char* v)

{

	return _atoi64(v);

}



/*

 *	2008-12-15 将 v.GetBuffer 转换改为 (LPCTSTR)

 */

__int64 Convert::ToInt64(const CString& v)

{

	return ToInt64((LPCTSTR)v);

}



__int64 Convert::ToInt64(const string& v)

{

	return ToInt64(v.c_str());

}



__int64 Convert::ToInt64(const wstring& v)

{

	return ToInt64(ToString(v));

}



/*

 *	To Long

 */

long Convert::ToLong(char* v)

{

	return atol(v);

}



long Convert::ToLong(wchar_t* v)

{

	string str = ToString(v);

	return ToLong(str);

}



long Convert::ToLong(const char* v)

{

	return atol(v);

}



/*

 *	2005-12-15 将 v.GetBuffer 转换改为 (LPCTSTR)

 */

long Convert::ToLong(const CString& v)

{

	return ToLong((LPCTSTR)v);

}



long Convert::ToLong(const string& v)

{

	return ToLong(v.c_str());

}



long Convert::ToLong(const wstring& v)

{

	long i = 0;

	return i;

}



/*

 *	To unsigned long

 */

unsigned long Convert::ToUnLong(char* v)

{

	char* end;

	return strtoul(v,&end,10);

}



unsigned long Convert::ToUnLong(const char* v)

{

	char* end;

	return strtoul(v,&end,10);

}



unsigned long Convert::ToUnLong(wchar_t* v)

{

	wchar_t* end;



	return wcstoul(v,&end,10);

}



unsigned long Convert::ToUnLong(const string& v)

{

	return ToUnLong(v.c_str());

}



unsigned long Convert::ToUnLong(const wstring& v)

{

	string s = ToString(v);

	return ToUnLong(s);

}



/*

 *	2008-12-15 将 v.GetBuffer 转换改为 (LPCTSTR)

 */

unsigned long Convert::ToUnLong(const CString& v)

{

	return ToUnLong((LPCTSTR)v);

}



/*

 *	To Double

 */

double Convert::ToDouble(const string& v)

{

	return ToDouble(v.c_str());

}



double Convert::ToDouble(char* v)

{

	char *end;

	

	return strtol(v,&end,10);

}



double Convert::ToDouble(const char* v)

{

	char *end;

	

	return strtol(v,&end,10);

}



double Convert::ToDouble(wchar_t* v)

{

	wchar_t* end;



	return wcstod( v,&end);

}



/*

 *	2008-12-15 将 v.GetBuffer 改为 (LPCTSTR)

 */

double Convert::ToDouble(const CString& v)

{

	char* end;



	return strtol((LPCTSTR)v,&end,10);

}



double Convert::ToDouble(const wstring& v)

{

	string s = ToString(v);

	return ToDouble(s);

}



/*

 *	To std::string

 */

string Convert::ToString(int v)

{

	char *vs = new char[sizeof(int)];



	itoa(v,vs,10);

	string sv(vs);

	return sv;

}



string Convert::ToString(float v)

{

	char fs[sizeof(v)];



	ZeroMemory(fs,sizeof(v));

	sprintf(fs,"%f",v);

	return ToString(fs);

}



string Convert::ToString(double v)

{

	int decimal;

	int sign;

	char *buffer;

	int precision = 10;



	buffer = _ecvt( v, precision, &decimal, &sign);

	return string(buffer);

}



string Convert::ToString(long v)

{

	char lv[sizeof(v)];



	_ltoa(v, lv, 10);

	return string(lv);

}



string Convert::ToString(char* v)

{

	string sv(v);

	return sv;

}



string Convert::ToString(const char* v)

{

	return string(v);

}



/*

 *	2008-12-15 将 v.GetBuffer 改为 (LPCTSTR)

 */

string Convert::ToString(const CString& v)

{

	return string((LPCTSTR)v);

}



string Convert::ToString(const wstring& v)

{

	string cs;

	return cs;

}



string Convert::ToString(wchar_t* v)

{

	char cstr[sizeof(v)];

	

	WideCharToMultiByte(CP_ACP,WC_COMPOSITECHECK,v,-1,cstr,sizeof(CString),NULL,NULL);

	return string(cstr);

}



/*

 *	To wstring

 */

wstring Convert::ToWString(int v)

{

	wchar_t wv[sizeof(int)];



	_itow(v, wv,10);

	return wstring(wv);

}



wstring Convert::ToWString(long v)

{

	wchar_t wv[sizeof(v)];



	_ltow(v, wv, 10);

	return wstring(wv);

}



wstring Convert::ToWString(unsigned long v)

{

	wchar_t wc[sizeof(v)];



	_ultow(v, wc, 10);

	return ToWString(wc);

}



wstring Convert::ToWString(char* v)

{

	wchar_t wschar[sizeof(v) * 2];



	long len = MultiByteToWideChar(CP_ACP,0,v,strlen(v),wschar,sizeof(wschar));

	wschar[len] = '\0'; 

	return wstring(wschar);

}



wstring Convert::ToWString(const char* v)

{

	return ToWString(v);

}



wstring Convert::ToWString(wchar_t* v)

{

	return wstring(v);

}



wstring Convert::ToWString(const CString& v)

{

	return wstring(v.AllocSysString());

}



wstring Convert::ToWString(const string& v)

{

	wchar_t wcs[sizeof(v) * 2];

	

	setlocale(LC_CTYPE, "");  //很重要，没有这一句，转换会失败

	mbstowcs(wcs, v.c_str(),v.size());

	return wstring(wcs);

}



/*

 *	UTF8 To WString

 */

wstring Convert::UTF8ToWString(char* utf8)

{

	wchar_t wschar[sizeof(utf8) * 2];

	

	long len = MultiByteToWideChar(CP_UTF8,0,utf8,strlen(utf8),wschar,sizeof(wschar));

	wschar[len] = '\0'; 

	wstring sv(wschar);

	return sv;

}



wstring Convert::UTF7ToWString(char* utf7)

{

	wchar_t wschar[sizeof(utf7) * 2];



	long len = MultiByteToWideChar(CP_UTF7,0,utf7,strlen(utf7),wschar,sizeof(wschar));

	wschar[len] = '\0'; 

	wstring sv(wschar);

	return sv;

}



/*

 *	To BSTR

 */

BSTR Convert::ToBSTR(char* v)

{

	CString s = CString(v);

	return s.AllocSysString();

}

BSTR Convert::ToBSTR(const char* v)

{

	return ToBSTR(v);

}

BSTR Convert::ToBSTR(const CString& v)

{

	return v.AllocSysString();

}

BSTR Convert::ToBSTR(const string& v)

{

	return ToBSTR(v.c_str());

}

BSTR Convert::ToBSTR(const wstring& v)

{

	string s = ToString(v);

	return ToBSTR(s);

}

BSTR Convert::ToBSTR(wchar_t* v)

{

	string s = ToString(v);

	return ToBSTR(s);

}

BSTR Convert::ToBSTR(int v)

{

	string s = ToString(v);

	return ToBSTR(s);

}

BSTR Convert::ToBSTR(long v)

{

	string s = ToString(v);

	return ToBSTR(s);

}

BSTR Convert::ToBSTR(double v)

{

	string s = ToString(v);

	return ToBSTR(s);

}

BSTR Convert::ToBSTR(float v)

{

	string s = ToString(v);

	return ToBSTR(v);

}