不解析配置内容，只读取文件内容，剪去注释和首尾空格后写入缓存: vector<string> 中。供其他方法使用。
代码是在做一个MFC小工具时写的。
ReadProtocol.h
复制代码 代码如下:
/**
* 从文件中 读取 protocol 的内容 写入缓存
* 供外部方法使用
* Alex Liu, 2014
*/
#pragma once
#include <vector>
#include <map>
#include <list>
#include <string>
using namespace std;
#defineMAX_FILEPATH512
#define COMMENT_FLG'#'
#define SECTION_BEGIN_FLG'['
#define SECTION_END_FLG']'
class ReadProtocol {
public:
ReadProtocol(char* FilePath);
~ReadProtocol();
/**
* 返回值为 errMsg 的地址 为了方便链式调用
* 缺省返回 "成功"
*/
char* GetErrInfo(char* errMsg, int errNo = 0);
/**
* 逐行读取文件内容 写入 m_StrVect
* 使用 vector::push_back() 写入
* return 0 成功 < 0 失败 可根据返回值 GetErrInfo
*/
int ReadIniFile();
/**
* 获取根据目录获取一个
* 使用 vector::push_back() 写入
* return 0 成功 < 0 失败 可根据返回值 GetErrInfo
*/
int GetOneSection(string Section, list<string> &Protocol);
private:
void PushBackToVector(string oneLine);
private:
char m_IniFile[MAX_FILEPATH];
string m_ErrPos;
map<string, unsigned int> m_SectionMap;
vector<string> m_StrVect;
};
ReadProtocol.cpp
复制代码 代码如下:
//
//#include "stdafx.h"
#include <fstream>
#include "ReadProtocol.h"
//去掉字符串首尾的空格
static string strTrim(string aStr)
{
string s = aStr;
unsigned int first, last;
if (string::npos != (first = s.find_first_not_of(' ') ))
s = s.substr(first, s.length()-first);
if (string::npos != (last = s.find_last_not_of(' ') ))
s = s.substr(0, last+1);
return s;
}
///=====================================================================================
ReadProtocol::ReadProtocol(char* FilePath)
{
int iLen = (strlen(FilePath) > MAX_FILEPATH) ? MAX_FILEPATH : strlen(FilePath);
memset(m_IniFile, 0, MAX_FILEPATH);
memcpy(m_IniFile, FilePath, iLen);
}
ReadProtocol::~ReadProtocol()
{
m_SectionMap.clear();
m_StrVect.clear();
}
int ReadProtocol::GetOneSection(string Section, list<string> &Protocol)
{
unsigned int Start = 0;
// 注意这里不能使用 [] 运算符
map<string, unsigned int>::iterator itr = m_SectionMap.find(Section);
if (m_SectionMap.end() == itr)
{
m_ErrPos = Section;
return -5;// Unknown Section!!
}
else
{
Start = itr->second;
}
vector<string>::iterator it = m_StrVect.begin() + Start + 1;
for (; it!=m_StrVect.end(); ++it)
{
unsigned int First, Last;
First = it->find_first_of ( SECTION_BEGIN_FLG );
Last = it->find_last_of ( SECTION_END_FLG );
// stop when the next Section
if( string::npos != First && string::npos != Last)
{
break;
}
Protocol.push_back(*it);
}
return (int)Protocol.size();
}
int ReadProtocol::ReadIniFile()
{
ifstream fin(m_IniFile);
if (!fin.is_open())
{
return -1;//can'topen file
}
string strLine;
unsigned int Last;
while (std::getline(fin, strLine).good())
{
if ( string::npos !=(Last = strLine.find_last_not_of('r') ))
{
//delete r
strLine = strLine.substr(0, Last + 1);
}
PushBackToVector(strLine);
}
fin.close();
if (m_StrVect.empty())
{
return -2;//get noting from file
}
return 0;
}
void ReadProtocol::PushBackToVector(string oneLine)
{
unsigned int uPos;
//去掉行尾注释
if ( string::npos != (uPos = oneLine.find_first_of( COMMENT_FLG ) ) )
{
oneLine = oneLine.substr(0, uPos + 1);
}
//去首尾空格
oneLine = strTrim(oneLine);
if (oneLine.empty() || oneLine.length() < 2)return;
//一行只能有一条记录
unsigned int First, Last;
First = oneLine.find_first_of(SECTION_BEGIN_FLG);
Last = oneLine.find_last_of(SECTION_END_FLG);
// is Section
if( string::npos != First && string::npos != Last)
{
m_SectionMap[ oneLine.substr(First + 1, Last - First - 1) ] = m_StrVect.size();
}
m_StrVect.push_back(oneLine);
}
char* ReadProtocol::GetErrInfo(char* errMsg, int errNo)
{
string errInfo;
switch (errNo)
{
case 0:
{
errInfo = "Success!";
break;
}
case -1:
{
char Path[1024] = {0};
int pLength = 1024;
GetCurrentDirectory(pLength, Path);
errInfo.append("Can't open file. The file name is:==>"");
errInfo.append( m_IniFile);
errInfo.append(""rnMaybe no such file in Path:");
errInfo.append(Path);
break;
}
case -2:
{
errInfo = "Get noting from file: ";
errInfo.append(m_IniFile);
break;
}
case -3:
{
errInfo = "Analyze file failed. In ==> ";
errInfo.append(m_ErrPos);
break;
}
case -5:
{
errInfo = "rnUnknown Section!! ==> "[";
errInfo.append(m_ErrPos);
errInfo.append("]"rn请检查配置文件中是否有遗漏。");
break;
}
default:
{
errInfo = "请按照正确步骤使用";
}
}
memcpy(errMsg, errInfo.c_str(), errInfo.length());
return errMsg;
}
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