配置文件读写案例

cfg.h

#ifndef _CFG_OP_H_#define _CFG_OP_H_#ifdef  __cplusplusextern "C" {#endif//写配置文件int WriteCfgItem(char *PFilename/*in*/,char *PKey/*in*/,char *PValue/*in*/,char *PValuelen/*in*/);//读配置文件int GetCfgItem(char *filename/*in*/,char*key/*in*/,char *value/*in*/,int *PValuelen/*out*/);//去除空格函数int trimSpace(char *instr,char *outstr);int trimspace(char *instr,char *outstr);#ifdef  __cplusplus}#endif#endif

cfg.c

#include <stdio.h>#include <string.h>#include <stdlib.h>#define MAXLINE 2048//写配置文件int WriteCfgItem(char *PFilename/*in*/,char *PKey/*in*/,char *PValue/*in*/,char *PValuelen/*in*/){int ret = 0;FILE* fp;int length = 0;char *temp = NULL;char linebuf[MAXLINE];char filebuf[1024*8]={0};//文件缓冲区 int iTag = 0;//判断传参是否正确if( PFilename==NULL || PKey==NULL || PValue==NULL ){ret = -1;printf("func WriteCfgItem() 参数 error %d.\n",ret);return ret;}//以追加的方式打开文件fp = fopen(PFilename,"a+");//判断是否打开错误if( fp == NULL ){ret = -2;printf("func WriteCfgItem() open error %d.\n",ret);return ret;}//存储文件长度fseek(fp,0L,SEEK_END);//文件指针定位到文件末尾      length = ftell(fp);//返回长度      fseek(fp,0L,SEEK_SET);//文件指针定位到文件开头  //判断文件是否大于8Kif( length > 1024*8 ){ret = -3;printf("func WriteCfgItem() length error %d.\n",ret);return ret;}//扫描全文件，判断key是否已存在，无则追加while(!feof(fp)){memset(linebuf,0,MAXLINE);temp = fgets(linebuf,MAXLINE,fp);//判空跳出if( temp == NULL ){break;}//查找关键字temp = strstr(linebuf,PKey);if( temp != NULL ){//关键字在本行//覆盖本行文件sprintf(linebuf,"%s = %s\n",PKey,PValue);strcat(filebuf,linebuf);iTag = 1;}else{//关键字不在本行strcat(filebuf,linebuf);//追加本行到filebuf中              continue;//继续下轮循环  }}//文件最终处理if(iTag == 0)//追加{ret = fprintf(fp,"%s = %s\n",PKey,PValue);if( ret == 0 ){ret = -4;printf("func WriteCfgItem() write error %d.\n",ret);return ret;}else{fclose(fp);}}else{//覆盖旧文件if( fp != NULL ){fclose(fp);}fp = fopen(PFilename,"w+t");if( fp == NULL ){ret = -5;printf("func WriteCfgItem() open error %d.\n",ret);return ret;}ret = fputs(filebuf,fp);if ( ret < 0 )          {              printf("func fputs err \n");              return ret;          }          if (fp!=NULL)          {              fclose(fp);          }  }return 0;}//读配置文件int GetCfgItem(char *filename/*in*/,char *key/*in*/,char *value/*in*/,int *PValuelen/*out*/){int ret = 0;FILE* fp = NULL;char linebuf[MAXLINE];char *ptemp = NULL;//以只读方式打开文件fp = fopen(filename,"r");//判断文件是否打开成功if(fp == NULL){ret = -1;printf("func open() error %d.\n",ret);}//判断是否读完文件while(!feof(fp)){//清空存储区memset(linebuf,0,MAXLINE);//整行读取文件fgets(linebuf,MAXLINE,fp);//printf("linebuf = %s\n",linebuf);//判断是否存在等号ptemp = strchr(linebuf,'=');if(ptemp == NULL){continue;}//判断并进行进行挖串操作ptemp = strstr(linebuf,key);if(ptemp == NULL){continue;}ptemp = ptemp + strlen(key);ptemp = strchr(linebuf,'=');if(ptemp == NULL){continue;}ptemp = ptemp + 1;ret = trimspace(ptemp,value);if(ret != 0){ret = -2;printf("func trimspace error %d.\n",ret);return ret;}}if(fp != NULL)fclose(fp);return ret;}//挖串int trimspace(char *instr,char *outstr){int ret = 0;char *p = NULL;p = instr;if( p == NULL){ret = -1;printf("func trimspace error %d.\n",ret);return ret;}while(*(p++) != '\0'){if(*p != ' '){*outstr++ = *p;}}*outstr = '\0';return ret;}//挖串int trimSpace(char*inStr,char*out)    {        char *p = inStr;        int ret = 0;        int i;        if (p==NULL)        {            ret = -1;            return;        }        for (i=0;p[i]!='\0';i++)        {            if (p[i]!=' ')            {                *out++ = p[i];            }        }        *out='\0';          return ret;    }    

test_cfg.c

#include <stdio.h>#include <string.h>#include <stdlib.h>#include "cfg_op.h"#define CFGNAME "d:/cfg.ini"void menu_display(){printf("------------------------------\n");printf("1.读文件测试\n");printf("2.写文件测试\n");printf("0.退出\n");printf("------------------------------\n");printf("请输入选项:");}//写配置文件int WriteCfg(){char key[1024] = {0};char value[1024] = {0};int ret = 0;printf("\n请键入key:");scanf("%s",key);printf("\n请键入value:");scanf("%s",value);ret = WriteCfgItem(CFGNAME/*in*/,key/*in*/,value/*in*/,strlen(value)/*in*/);if(ret != 0){printf("func WriteCfg() WriteCfgItem error %d!\n",ret);return ret;}printf("你的输入是:%s = %s\n",key,value);return 0;}//读配置文件int GetCfg(){//GetCfgItem(char *filename/*in*/,char*key/*in*/,char *value/*in*/,char *PValuelen/*out*/);char key[1024] = {0};char value[1024] = {0};int vlen = 0;int ret = 0;printf("\n请键入key:");scanf("%s",key);ret = GetCfgItem(CFGNAME/*in*/,key/*in*/,value/*in*/,&vlen/*in*/);if(ret != 0){printf("func GetCfgItem() error %d!\n",ret);return ret;}printf("value:%s\n",value);return 0;}void main(){int choice;for(;;){//显示菜单menu_display();//输入选项scanf("%d",&choice);switch(choice){case 1:GetCfg();break;case 2:WriteCfg();break;case 0:exit(0);default:exit(0);}}system("pause");}