mystring.cpp

来自「一个很好的string类,类似与Windows 下CString」· C++ 代码 · 共 354 行

#include <string.h>
#include <stdarg.h>
#include <stdio.h>

#include "MyString.h"

CString::CString():_data(0)
{
  _data=new char[1];
  _data[0]='\0';
}
CString::CString(const char *str):_data(0)
{
  if(str)
  {
    _data=new char[strlen(str)+1];
    strcpy(_data,str);
  }
  else
  {
    _data=new char[1];
    _data[0]='\0';            
  }
}
CString::CString(CString &str):_data(0)
{
  //必须在拷贝函数中为动态分配空间的指针分配空间
  _data=new char[str.GetLength()+1];
  strcpy(_data,str._data);
}
CString::~CString()
{
  delete []_data;
}
//return the length of this string,not counting the null-terminating character.
int CString::GetLength() const
{
  return strlen(_data);
}
CString & CString::operator=(const CString &str)
{       
  if(this==&str) //can't be "this==str"
  {
    return *this;
  }
  delete []_data;//for the previous 'new'
  _data=new char[str.GetLength()+1];
  strcpy(_data,str._data);
  return *this;
}
//the value returned by c_str points to the internal character
//array referenced by the _data property
const char * CString::c_str()const
{
  return _data;
}
CString&  CString::Format(const char* format, ...)
{
#ifdef WIN32
    delete []_data;
    va_list paramList;
    va_start(paramList, format);
    int size = vsnprintf(NULL, 0, format, paramList);
    _data=new char[size+1];
    memset(_data,0x00,size+1);
    vsnprintf(_data, size, format, paramList);//Only for WIN32
    va_end(paramList);
    return *this;
#else
    delete []_data;
    _data=new char[1024*5];//maxsize:5k,may cause overflow
    va_list paramList;
    va_start(paramList, format);
    vsprintf(_data,format, paramList);
    va_end(paramList);
    return *this;
#endif
}

CString CString::operator+(const CString &str)
{
  CString tmp;
  tmp=*this;
  delete []_data;
  _data=new char[tmp.GetLength()+str.GetLength()+1];
  memset(_data,0x00,tmp.GetLength()+str.GetLength()+1);
  strcpy(_data,tmp.c_str());
  strcat(_data,str.c_str());
  return *this;
}

CString  CString::operator +(const char* str)
{
  CString tmp;
  tmp=*this;
  delete []_data;
  _data=new char[tmp.GetLength()+strlen(str)+1];
  memset(_data,0x00,tmp.GetLength()+strlen(str)+1);
  strcpy(_data,tmp.c_str());
  strcat(_data,str);
  return *this;
}

CString &CString::operator +=(const CString& rhs)
{
  CString tmp;
  tmp=*this;
  delete []_data;
  _data=new char[tmp.GetLength()+rhs.GetLength()+1];
  memset(_data,0x00,tmp.GetLength()+rhs.GetLength()+1);
  strcpy(_data,tmp.c_str());
  strcat(_data,rhs.c_str());
  return *this;
}

char &CString::operator [](const int idx)
{
  if( (idx<0) || (idx>GetLength()-1) )
    return cTmp;//if over range,return the reference of cTmp 
  else
    return _data[idx];
}

bool  CString::operator !=(const CString& rhs) const
{
   if( strcmp(_data,rhs.c_str())!=0)
     return true;
   else
     return false;
}

bool  CString::operator <(const CString& rhs) const
{
   if( strcmp(_data,rhs.c_str())<0)
     return true;
   else
     return false;
}

bool  CString::operator <=(const CString& rhs) const
{
   if( strcmp(_data,rhs.c_str())<=0)
     return true;
   else
     return false;
}

bool  CString::operator ==(const CString& rhs) const
{
   if( strcmp(_data,rhs.c_str())==0)
     return true;
   else
     return false;
}

bool  CString::operator >(const CString& rhs) const
{
   if( strcmp(_data,rhs.c_str())>0)
     return true;
   else
     return false;
}

bool  CString::operator >=(const CString& rhs) const
{
   if( strcmp(_data,rhs.c_str())>=0)
     return true;
   else
     return false;
}

CString  CString::TrimLeft() const
{
  CString Result;
  char *pDest,*pTmp;
  pTmp=new char[GetLength()+1];
  memset(pTmp,0x00,GetLength()+1);
  strcpy(pTmp,_data);
  pDest=pTmp;

  for(int i=0;i<GetLength();i++)
  {
    if( (*pDest==' ') || (*pDest=='\n') || (*pDest=='\t') )
      pDest++;
    else
      break;
  }
  Result=pDest;
  delete []pTmp;
  return Result;
}

CString  CString::TrimRight() const
{
  CString Result;
  char *pDest,*pTmp;
  pTmp=new char[GetLength()+1];
  memset(pTmp,0x00,GetLength()+1);
  strcpy(pTmp,_data);
  pDest=pTmp+GetLength()-1;

  for(int i=GetLength();i>0;i--)
  {
    if( (*pDest==' ') || (*pDest=='\n') || (*pDest=='\t') )
      pDest--;
    else
      break;
  }
  *(++pDest)=0;//Cut to here
  Result=pTmp;
  delete []pTmp;
  return Result;
}

CString  CString::Trim() const
{
  CString Result;
  char *pDest,*pTmp,*p;
  pTmp=new char[GetLength()+1];
  memset(pTmp,0x00,GetLength()+1);
  strcpy(pTmp,_data);
  pDest=pTmp;

  for(int i=0;i<GetLength();i++)
  {
    if( (*pDest==' ') || (*pDest=='\n') || (*pDest=='\t') )
      pDest++;
    else
      break;
  }
  p=pTmp+GetLength()-1;

  for(int j=GetLength();j>0;j--)
  {
    if( (*p==' ') || (*p=='\n') || (*p=='\t') )
      p--;
    else
      break;
  }
  *(++p)=0;//Cut to here

  Result=pDest;
  delete []pTmp;
  return Result;
}

CString  CString::UpperCase() const
{
  CString Result;
  char *pTmp;
  pTmp=new char[GetLength()+1];
  memset(pTmp,0x00,GetLength()+1);
  strcpy(pTmp,_data);
  for(int i=0;i<GetLength();i++)
  {
    if( (pTmp[i]>='a') && (pTmp[i]<='z') )
    {
      pTmp[i]-=('a'-'A');
    }
  }
  Result=pTmp;
  delete []pTmp;
  return Result;
}

CString  CString::LowerCase() const
{
  CString Result;
  char *pTmp;
  pTmp=new char[GetLength()+1];
  memset(pTmp,0x00,GetLength()+1);
  strcpy(pTmp,_data);
  for(int i=0;i<GetLength();i++)
  {
    if( (pTmp[i]>='A') && (pTmp[i]<='Z') )
    {
      pTmp[i]+=('a'-'A');
    }
  }
  Result=pTmp;
  delete []pTmp;
  return Result;
}

CString  CString::StringOfChar(char ch, int count)const
{
  CString str;
  char *pTmp;
  pTmp=new char[count+1];
  memset(pTmp,0x00,count+1);
  for(int i=0;i<count;i++)
  {
    pTmp[i]=ch;
  }
  str=pTmp;
  delete []pTmp;
  return str;
}

//返回被分隔符分割的字符串,如
//GetDelimitedString("ab,cd,ef",",",1) 返回"cd"
//GetDelimitedString("ab,,ef",",",1) 返回"ef"
CString CString::GetDelimitedString(const char *delimiter,int index)
{
   CString strResult;
   int iIndex=0;
   int iLength=GetLength()+1;
   char *pSource=new char[iLength];
   char *p=NULL;
   memset(pSource,0,iLength);
   memcpy(pSource,_data,iLength);
   p=strtok(pSource,delimiter);
   while(p)
   {
     if(iIndex==index)
     {
        strResult=CString(p);
        break;
     }
     iIndex++;
     p=strtok(NULL,delimiter);
   }
   delete []pSource;
   pSource=NULL;
   return strResult;
}
//////////////////////////////////////////////////////////////////////////////
int	CString::Find(const char cCh,int nStart=0)
{
	return -1;
}
int	CString::Find(const char *pStr,int nStart=0)
{
	return -1;
}
void CString::MakeReverse()
{
}
CString CString::Left(int nCount)
{
	CString strResult;
	return strResult;
}
CString CString::Right(int nCount)
{
	CString strResult;
	return strResult;
}
CString CString::Mid(int nStart,int nCount)
{
	CString strResult;
	return strResult;
}