实例：常用数据类型之间的相互转换

秒速五厘米 2022-08-24 11:55 218阅读 0赞

常用的数据类型之间的相互转换，包括：int与CString，double与CString，float与CString，

char\* 与CString ,string 与CString ,char 与string ,WCHAR\*(BSTR) 与CString，WCHAR\*(BSTR) 与char\*

//int to CString
    CString CMFCDataType::IntConvertCString(const int i)
    {
    CString strTemp;
    strTemp.Format(_T("%d"), i);
    return strTemp;
    }
     
    //CString to int
    int CMFCDataType::CStringConvertInt(const CString str)
    {
    int itemp = _wtoi(str);
    return itemp;
    }
     
    //float to CString
    CString CMFCDataType::FloatConvertCString(const float f)
    {
    CString strTemp;
    strTemp.Format(_T("%f"), f);
    return strTemp;
    }
     
    //CString to float
    float CMFCDataType::CStringConvertFloat(CString str)
    { 
    float ftemp = _wtof(str);
    return ftemp;
    }
     
    //double to CString
    CString CMFCDataType::DoubleConvertCString(const double d)
    {
    CString strTemp;
    strTemp.Format(_T("%f"), d);
    return strTemp;
    }
     
    //CString to double
    double CMFCDataType::CStringConvertDouble(const CString str)
    {
    double  dtemp = _wtol(str);
    return dtemp;
    }
     
    //char* to CString
    CString CMFCDataType::LPSTRConvertCString(const char* ch)
    {
    CString strTemp;
    strTemp.Format(_T("%s"), ch);
    return strTemp;
    }
     
    //CString to char*
    char* CMFCDataType::CStringConvertLPSTR(const CString str)
    {
    //将CString类转换成char*(LPSTR)类型
    方法1 强制转换
    //LPSTR lpsz =(LPSTR)(LPCTSTR)str;
    //return lpsz;
     
    //方法二 使用strcpy
    LPTSTR lpsz = new TCHAR[str.GetLength()+1];
    _tcscpy(lpsz, str);
    LPSTR lpst=(LPSTR)lpsz;
    return lpst;
     
    }
     
    //string to CString
    CString CMFCDataType::StringConvertCString(const std::string str)
    {
    CString strTemp;
    strTemp = str.c_str();
    return strTemp;
    }

示例：

std::string CMFCDataType::CStringConvertstring(CString str)
    {
    //Method One
    std::string strstring = CT2A(str.GetBuffer());
    //GetBuffer()后一定要ReleaseBuffer(),否则就没有释放缓冲区所占的空间.
    str.ReleaseBuffer();
    return strstring;
     
    Method Two
    //std::string strstring( CW2A( str.GetString() ) ); 
    //return strstring;
     
    Method Three
    //CT2CA pszstrtemp(str); 
    //std::string strstring(pszstrtemp);
    //return strstring;
     
    Method Four
    //std::wstring ws(str); 
    //std::string strstring;  
    //strstring.assign(ws.begin(), ws.end());
    //return strstring;
    }
     
     
     
    //char to std::string
    std::string CMFCDataType::CharConvertstring(const char str)
    {
    std::string stringtemp(&str);
    return stringtemp;
    }
     
    //std::string to char
    const char* CMFCDataType::StringConvertchar(const std::string str)
    {
    //方法一
    const char* chtemp1 = str.c_str();
    //方法二
    const char* chtemp2 = str.data();
     
    /*printf("%s%s",chtemp1,chtemp2);*/
     
    return chtemp1;
    }
     
    //WCHAR*(BSTR) to CString
    CString CMFCDataType::BSTRConvertCString(const WCHAR* wch)
    {
    //BSTR bstrText = ::SysAllocString(L"Test");
    CString str;
    str.Empty();
    str = wch;
    //或
    //CString str(wch);
    return str;
     
    }
     
    //CString to WCHAR*(BSTR)
    WCHAR* CMFCDataType::CStringConvertBSTR(const CString str)
    {
    return str.AllocSysString();
     
    //BSTR bstrText = str.AllocSysString();
    //SysFreeString(bstrText); // 用完释放
     
    }
     
    //WCHAR*(BSTR) to char*(LPSTR)
    /*char**/LPSTR CMFCDataType::BSTRConvertLPSTR(const WCHAR* wch)
    {
    _bstr_t btemp = wch;
    char* lpsz = btemp;
    return lpsz;
    }
     
    //char*(LPSTR) to WCHAR*(BSTR)
    WCHAR* CMFCDataType::LPSTRConvertBSTR(const char* ch)
    {
    BSTR bstr = _bstr_t(ch);
    return bstr;
    }
     
    引用示例：
    void CDataTypeConversionDlg::OnBnClickedBtnConvert()
    {
    //int 转 CString
    /*int i= 20;
    CString str=m_CMFCDataType.IntConvertCString(i);
    int t= str.GetLength();*/
    //CString 转 int
    /*CString str1=_T("30");
    int t=m_CMFCDataType.CStringConvertInt(str1);*///t==30
     
    float 转 CString
    //float f= 20.5;
    //CString str=m_CMFCDataType.FloatConvertCString(f);
     
    double 转 CString
    /*double d= 20.025;
    CString str=m_CMFCDataType.DoubleConvertCString(d);*/
     
    //CString 转 float
    //CString str1=_T("30.27");
    //float ftemp=m_CMFCDataType.CStringConvertFloat(str1);//t==30.270000
     
    CString 转 double
    //CString str1=_T("30.27458");
    //double dtemp=m_CMFCDataType.CStringConvertDouble(str1);//t==
     
    //CString str1=_T("");
    //int t=m_CMFCDataType.CStringConvertInt(str1);//t==0
     
    /*CString strTemp;
    std::string str("sadfg");
    strTemp = m_CMFCDataType.StringConvertCString(str);
    MessageBox(strTemp);*/
     
    /*CString strTemp=_T("asdfg");
    std::string str;
    str = m_CMFCDataType.CStringConvertstring(strTemp);*/
     
    /*char ch = 'abcd';
    char* c1 = &ch;
    CString str=m_CMFCDataType.LPSTRConvertCString(c1);
    delete c1;*/
     
    //char ch= 'abcd';
    //std::string s=m_CMFCDataType.CharConvertstring(ch);//s='d'
    //char ch= 'b';
    //std::string s=m_CMFCDataType.CharConvertstring(ch);//s='b'
     
    //std::string str("sadfg");
    //const char* chtemp1=m_CMFCDataType.StringConvertchar(str);
     
    //char str2[20];
    //strcpy(str2,chtemp1);
    //printf("%s,\n",str);//str 为stdfg
    //2014-04-29
    //char*转换为CString 
    //定义一个字符串数组 方式 5种
    //char chArray[] = "This is a test";
    //char * p1 = "This is a test";
    //LPSTR p2 = "This is a test";
    //或在已定义Unicode应的用程序中
    //TCHAR * p3 = _T("This is a test");
    //或
    //LPTSTR p4 = _T("This is a test");
     
    BSTRConvertCString
    //BSTR bstrText = ::SysAllocString(L"Test");
    //CString strtemp=m_CMFCDataType.BSTRConvertCString(bstrText);//strtemp='Test'
    CStringConvertBSTR
    //CString strtemp=_T("saddsf");
    //BSTR bstrText = m_CMFCDataType.CStringConvertBSTR(strtemp);
     
    BSTRConvertCString
    //BSTR bstrText = ::SysAllocString(L"Test");
    //LPSTR chtemp=m_CMFCDataType.BSTRConvertLPSTR(bstrText);//strtemp='Test'
    //CString str;
    //str.Format(_T("%s"),chtemp);
     
    LPSTRConvertBSTR
    //char* ch="asdd";
    //BSTR bstrText = m_CMFCDataType.LPSTRConvertBSTR(ch);
    }