这篇文章简单讨论一下ini文件。
一.什么是ini文件
ini文件其实就是一种配置文件，常见于windows的系统配置文件，当然也可以是其他用途，你的用法你说了算。
二.ini文件的格式一般是什么样的
看个例子
;这是注释 [section1] key1=value1 key2=value2 [section2] key3=value3 key4=value4
ini文件包括节（section）、键值对（通常称为参数，parameter）和注释（comment）。
1.节
1.每一个section包含若干个parameter。
2.每一个section独占一行，名称由[]包围，比如[sectionname]。
3.每一个section的生效范围，从当前section开始到下一个section的开始（或者文件结尾），这其中所有的parameter都属于这个section。
4.section不应该重复。
2.参数
1.parameter以键值对的形式存在，比如key=value。
2.同一个section中的parameter不应该重复。
3.注释
1.注释用;表示。
2.注释独占一行。
三.c 实现ini文件的解析
重点来了，这里展示一种c 解析ini文件的简易代码写法，主要是描述一种解析的思维，大致测试过了。
直接看代码
//inifile.h #ifndef inifile_h #define inifile_h #include#include #define err_mes_1 "输入值不合法" #define err_mes_2 "打开文件失败" #define err_mes_3 "配置项不存在" const char type_null = '0'; const char type_section = '1'; const char type_parameter = '2'; const char type_comment = '3'; typedef struct ininode { char m_type; std::string m_text; ininode* m_pprev; ininode* m_pnext; }ininode, * pininode; typedef struct inisec { pininode m_psection; pininode m_pparameter; std::string m_sectiontext; std::string m_parametertext; }inisec, * pinisec; class inifile { public: inifile(); ~inifile(); bool readinifile(const char* filepathname); bool writeinifile(const char* filepathname); bool writeparameter(const char* section, const char* key, const char* value); bool writeparameter(const char* section, const char* key, const bool value); bool writeparameter(const char* section, const char* key, const int value); bool writeparameter(const char* section, const char* key, const double value); std::string readparameter(const char* section, const char* key, const char* default); bool readparameter(const char* section, const char* key, const bool default); int readparameter(const char* section, const char* key, const int default); double readparameter(const char* section, const char* key, const double default); bool deleteparameter(const char* section, const char* key); bool deletesection(const char* section); int geterrcode(); std::string geterrmes(); protected: void freeinilist(); void createininode(); void trim(char* buffer); pininode findsection(const char* section); pinisec findparameter(const char* section, const char* key); void addininode(char type, const char* text); bool writeparameterpublic(const char* section, const char* key, const char* value); std::string readparameterpublic(const char* section, const char* key, const char* default); private: file* m_pinifilehandle; pininode m_pinilist; pininode m_pcurininode; int m_lasterrcode; std::string m_lasterrmes; }; #endif // !inifile_h
//inifile.cpp
#include "inifile.h"
inifile::inifile()
{
m_lasterrcode = 0;
m_lasterrmes = "";
m_pcurininode = nullptr;
m_pinifilehandle = nullptr;
m_pinilist = nullptr;
}
inifile::~inifile()
{
freeinilist();
fclose(m_pinifilehandle);
}
int inifile::geterrcode()
{
return m_lasterrcode;
}
std::string inifile::geterrmes()
{
return m_lasterrmes;
}
bool inifile::readinifile(const char* filepathname)
{
if (!strcmp(filepathname, ""))
{
m_lasterrcode = 1;
m_lasterrmes = err_mes_1;
return false;
}
if (!(m_pinifilehandle = fopen(filepathname, "r")))
{
m_lasterrcode = 2;
m_lasterrmes = err_mes_2;
return false;
}
freeinilist();
char filebuf[256] = { 0 };
char* pchr = nullptr;
while (fgets(filebuf, 256, m_pinifilehandle))
{
trim(filebuf);
createininode();
if (';' == filebuf[0])
{
m_pcurininode->m_type = type_comment;
}
else if ('[' == filebuf[0] && strchr(filebuf, ']'))
{
m_pcurininode->m_type = type_section;
}
else if (strchr(filebuf, '='))
{
m_pcurininode->m_type = type_parameter;
}
else
{
m_pcurininode->m_type = type_null;
}
m_pcurininode->m_text = filebuf;
}
fclose(m_pinifilehandle);
return true;
}
bool inifile::writeinifile(const char* filepathname)
{
if (!strcmp(filepathname, ""))
{
m_lasterrcode = 1;
m_lasterrmes = err_mes_1;
return false;
}
char filepathnamebat[256] = { 0 };
strcpy(filepathnamebat, filepathname);
strcat(filepathnamebat, ".bak");
file* fileinitemp = fopen(filepathname, "r");
file* filebattemp = fopen(filepathnamebat, "w");
if (!fileinitemp || !filebattemp)
{
m_lasterrcode = 2;
m_lasterrmes = err_mes_2;
return false;
}
char filestr[256] = { 0 };
while (fgets(filestr, 256, fileinitemp))
{
fprintf(filebattemp, "%s", filestr);
}
fclose(fileinitemp);
fclose(filebattemp);
if (!(m_pinifilehandle = fopen(filepathname, "w")))
{
m_lasterrcode = 2;
m_lasterrmes = err_mes_2;
return false;
}
m_pcurininode = m_pinilist;
while (m_pcurininode)
{
fprintf(m_pinifilehandle, "%s\n", m_pcurininode->m_text.data());
m_pcurininode = m_pcurininode->m_pnext;
}
fclose(m_pinifilehandle);
return true;
}
bool inifile::writeparameter(const char* section, const char* key, const char* value)
{
return writeparameterpublic(section, key, value);
}
bool inifile::writeparameter(const char* section, const char* key, const bool value)
{
char strvalue[256] = { 0 };
itoa(value, strvalue, 2);
return writeparameterpublic(section, key, strvalue);
}
bool inifile::writeparameter(const char* section, const char* key, const int value)
{
char strvalue[256] = { 0 };
itoa(value, strvalue, 10);
return writeparameterpublic(section, key, strvalue);
}
bool inifile::writeparameter(const char* section, const char* key, const double value)
{
char strvalue[256] = { 0 };
sprintf_s(strvalue, "%f", value);
return writeparameterpublic(section, key, strvalue);
}
std::string inifile::readparameter(const char* section, const char* key, const char* default)
{
return readparameterpublic(section, key, default);
}
bool inifile::readparameter(const char* section, const char* key, const bool default)
{
char defaultstring[2] = { 0 };
if (default)
{
defaultstring[0] = '1';
}
else
{
defaultstring[0] = '0';
}
std::string retstr = readparameterpublic(section, key, defaultstring);
return atoi(retstr.data());
}
int inifile::readparameter(const char* section, const char* key, const int default)
{
char defaultstring[256] = { 0 };
itoa(default, defaultstring, 10);
std::string retstr = readparameterpublic(section, key, defaultstring);
return atoi(retstr.data());
}
double inifile::readparameter(const char* section, const char* key, const double default)
{
char defaultstring[256] = { 0 };
sprintf_s(defaultstring, "%f", default);
std::string retstr = readparameterpublic(section, key, defaultstring);
return atof(retstr.data());
}
bool inifile::deleteparameter(const char* section, const char* key)
{
if (!strcmp(section, "") || !strcmp(key, ""))
{
m_lasterrcode = 1;
m_lasterrmes = err_mes_1;
return false;
}
pinisec pinisectemp = findparameter(section, key);
if (!pinisectemp)
{
m_lasterrcode = 3;
m_lasterrmes = err_mes_3;
return false;
}
m_pcurininode = pinisectemp->m_pparameter;
m_pcurininode->m_pprev->m_pnext = m_pcurininode->m_pnext;
if (m_pcurininode->m_pnext)
{
m_pcurininode->m_pnext->m_pprev = m_pcurininode->m_pprev;
}
delete m_pcurininode;
delete pinisectemp;
return true;
}
bool inifile::deletesection(const char* section)
{
if (!strcmp(section, ""))
{
m_lasterrcode = 1;
m_lasterrmes = err_mes_1;
return false;
}
pininode psectionininodetemp = findsection(section);
if (!psectionininodetemp)
{
m_lasterrcode = 3;
m_lasterrmes = err_mes_3;
return false;
}
pininode pcurnextininode = nullptr;
m_pcurininode = psectionininodetemp->m_pnext;
while (m_pcurininode && m_pcurininode->m_type == type_parameter)
{
pcurnextininode = m_pcurininode->m_pnext;
m_pcurininode->m_pprev->m_pnext = m_pcurininode->m_pnext;
if (m_pcurininode->m_pnext)
{
m_pcurininode->m_pnext->m_pprev = m_pcurininode->m_pprev;
}
delete m_pcurininode;
m_pcurininode = pcurnextininode;
}
m_pcurininode = psectionininodetemp;
m_pcurininode->m_pprev->m_pnext = m_pcurininode->m_pnext;
if (m_pcurininode->m_pnext)
{
m_pcurininode->m_pnext->m_pprev = m_pcurininode->m_pprev;
}
delete m_pcurininode;
return true;
}
void inifile::freeinilist()
{
if (nullptr == m_pinilist)
{
return;
}
pininode pnextininodetemp = nullptr;
while (nullptr != m_pinilist)
{
pnextininodetemp = m_pinilist->m_pnext;
delete m_pinilist;
m_pinilist = pnextininodetemp;
}
}
void inifile::createininode()
{
pininode pininodetemp = new ininode;
memset(pininodetemp, 0, sizeof(ininode));
if (nullptr == m_pinilist)
{
m_pinilist = pininodetemp;
m_pcurininode = pininodetemp;
return;
}
m_pcurininode = m_pinilist;
while (m_pcurininode->m_pnext)
{
m_pcurininode = m_pcurininode->m_pnext;
}
m_pcurininode->m_pnext = pininodetemp;
pininodetemp->m_pprev = m_pcurininode;
m_pcurininode = pininodetemp;
}
void inifile::trim(char* buffer)
{
int i = 0;
int len = strlen(buffer);
for (i = len - 1; i >= 0; i--)
{
if (' ' != buffer[i] && '\t' != buffer[i] && '\n' != buffer[i])
{
break;
}
buffer[i] = 0;
}
for (i = 0; i < len; i )
{
if (' ' != buffer[i] && '\t' != buffer[i] && '\n' != buffer[i])
{
break;
}
}
if (0 != i)
{
strncpy(buffer, buffer i, len - i);
buffer[len - i] = 0;
}
}
pininode inifile::findsection(const char* section)
{
m_pcurininode = m_pinilist;
while (m_pcurininode)
{
if (!strcmp(m_pcurininode->m_text.data(), section) && m_pcurininode->m_type == type_section)
{
return m_pcurininode;
}
m_pcurininode = m_pcurininode->m_pnext;
}
return nullptr;
}
pinisec inifile::findparameter(const char* section, const char* key)
{
m_pcurininode = m_pinilist;
pinisec pinisectemp = new inisec;
char buf[256] = { 0 };
char* pchr = nullptr;
while (m_pcurininode)
{
if (!strcmp(m_pcurininode->m_text.data(), section) && m_pcurininode->m_type == type_section)
{
pinisectemp->m_psection = m_pcurininode;
pinisectemp->m_sectiontext = m_pcurininode->m_text;
m_pcurininode = m_pcurininode->m_pnext;
while (m_pcurininode && m_pcurininode->m_type == type_parameter)
{
strcpy(buf, m_pcurininode->m_text.data());
if (pchr = strchr(buf, '='))
{
*pchr = 0;
trim(buf);
if (!strcmp(buf, key))
{
pinisectemp->m_pparameter = m_pcurininode;
pinisectemp->m_parametertext = m_pcurininode->m_text;
return pinisectemp;
}
}
m_pcurininode = m_pcurininode->m_pnext;
}
break;
}
m_pcurininode = m_pcurininode->m_pnext;
}
delete pinisectemp;
return nullptr;
}
void inifile::addininode(char type, const char* text)
{
if (type == type_section)
{
m_pcurininode->m_type = type_section;
m_pcurininode->m_text = text;
}
else if (type == type_parameter)
{
m_pcurininode->m_type = type_parameter;
m_pcurininode->m_text = text;
}
return;
}
bool inifile::writeparameterpublic(const char* section, const char* key, const char* value)
{
if (!strcmp(section, "") || !strcmp(key, "") || !strcmp(value, ""))
{
m_lasterrcode = 1;
m_lasterrmes = err_mes_1;
return false;
}
char parameter[256] = { 0 };
strcpy(parameter, key);
strcat(parameter, "=");
strcat(parameter, value);
pininode psectionnodetemp = findsection(section);
pinisec pinisectemp = nullptr;
if (!psectionnodetemp)
{
createininode();
addininode(type_section, section);
createininode();
addininode(type_parameter, parameter);
}
else
{
if (!(pinisectemp = findparameter(section, key)))
{
pininode pininodetemp = new ininode;
memset(pininodetemp, 0, sizeof(ininode));
pininodetemp->m_pnext = psectionnodetemp->m_pnext;
psectionnodetemp->m_pnext = pininodetemp;
if (pininodetemp->m_pnext)
{
pininodetemp->m_pnext->m_pprev = pininodetemp;
}
pininodetemp->m_pprev = psectionnodetemp;
m_pcurininode = pininodetemp;
addininode(type_parameter, parameter);
}
else
{
m_pcurininode = pinisectemp->m_pparameter;
addininode(type_parameter, parameter);
}
}
delete pinisectemp;
pinisectemp = nullptr;
return true;
}
std::string inifile::readparameterpublic(const char* section, const char* key, const char* default)
{
if (!strcmp(section, "") || !strcmp(key, "") || !strcmp(default, ""))
{
m_lasterrcode = 1;
m_lasterrmes = err_mes_1;
return {};
}
std::string ret;
pinisec pinisectemp = findparameter(section, key);
char* pchr = nullptr;
if (pinisectemp)
{
char buf[256] = { 0 };
strcpy(buf, pinisectemp->m_parametertext.data());
if (pchr = strchr(buf, '='))
{
strcpy(buf, pchr 1);
}
ret = buf;
}
else
{
ret = default;
}
delete pinisectemp;
return ret;
}
四.其他
说一个小技巧，如果担心格式写的不对，可以用熟悉的编辑器中设置文档格式这个功能调整一下，当然调整之后也要进行确认。
