C语言读取配置文件
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2022-06-24 20:49:29
c语言读取配置文件,配置文件的格式如下:
key1 = value1
key2 = value2 .
名值对以一个=链接,一条记录以换行符分割
头文件:
#include
#include...
c语言读取配置文件,配置文件的格式如下:
key1 = value1
key2 = value2 .
名值对以一个=链接,一条记录以换行符分割
头文件:
#include #include #include
函数原型:
void trim(char *strin, char *strout);//去除字符串首位空格 void getvalue(char * keyandvalue, char * key, char * value); //根据key得到value int writecfg(const char *filename/*in*/, const char *key/*in*/, const char *value/*in*/); //写入配置文件 void readcfg(const char *filename/*in*/, const char *key/*in*/, const char **value/*out*/); //读取配置文件
函数实现:
1 void trim(char *strin, char *strout){ 2 3 char *start, *end, *temp;//定义去除空格后字符串的头尾指针和遍历指针 4 5 temp = strin; 6 7 while (*temp == ' '){ 8 ++temp; 9 } 10 11 start = temp; //求得头指针 12 13 temp = strin + strlen(strin) - 1; //得到原字符串最后一个字符的指针(不是'\0') 14 15 while (*temp == ' '){ 16 --temp; 17 } 18 19 end = temp; //求得尾指针 20 21 22 for(strin = start; strin <= end; ){ 23 *strout++ = *strin++; 24 } 25 26 *strout = '\0'; 27 } 28 29 void getvalue(char * keyandvalue, char * key, char * value){ 30 31 char *p = keyandvalue; 32 33 p = strstr(keyandvalue, key); 34 if(p == null){ 35 //printf("没有key\n"); 36 return ; 37 } 38 39 p += strlen(key); 40 trim(p, value); 41 42 p = strstr(value, "="); 43 if(p == null){ 44 printf("没有=\n"); 45 return; 46 } 47 p+= strlen("="); 48 trim(p, value); 49 50 p = strstr(value, "="); 51 if(p != null){ 52 printf("多余的=\n"); 53 return; 54 } 55 p = value; 56 trim(p, value); 57 58 } 59 int writecfg(const char *filename/*in*/, const char *key/*in*/, const char *value/*in*/){ 60 61 file *pf = null; 62 char ftemp[flen] = {0}, fline[1024] = {0}, *fp; //文件缓存数组 63 long fsize = 0; 64 int reg = 0; 65 int exit = 0; 66 int i = 0; 67 68 pf = fopen(filename, "r+"); 69 if(pf == null){ 70 pf = fopen(filename, "w+"); 71 } 72 //获得文件大小 73 fseek(pf, 0, seek_end); // 将文件指针指向末尾 74 fsize = ftell(pf); 75 if(fsize > flen){ 76 printf("文件不能超过8k\n"); 77 reg = -1; 78 goto end; 79 } 80 fseek(pf, 0, seek_set); //将文件指针指向开头 81 82 //一行一行的读,如果存在key则修改value存到缓存数组中 83 while(!feof(pf)){ 84 fgets(fline, 1024, pf); 85 if(strstr(fline, key) != null && exit == 1) 86 strcpy(fline, ""); 87 if(strstr(fline, key) != null && exit == 0){ //判断key是否存在 88 exit = 1; 89 sprintf(fline,"%s = %s\n", key, value); 90 } 91 92 printf("fline = %s\n", fline); 93 strcat(ftemp, fline); 94 95 } 96 if(exit != 1){//如果不存在则把key value写入到最后一行 97 sprintf(fline,"%s = %s\n", key, value); 98 strcat(ftemp, fline); 99 } 100 if(pf != null){ 101 fclose(pf); 102 pf = fopen(filename, "w+"); 103 fp = (char *)malloc(sizeof(char) * strlen(ftemp) + 1); 104 strcpy(fp, ftemp); 105 fp[strlen(fp) - 1] = eof; 106 fputs(fp, pf); 107 if(fp != null){ 108 free(fp); 109 fp = null; 110 } 111 fclose(pf); 112 } 113 end : 114 if(pf != null) 115 fclose(pf); 116 //重新创建一个以filename命名的文件 117 return reg; 118 } 119 120 void readcfg(const char *filename/*in*/, const char *key/*in*/, const char **value/*out*/){ 121 122 file *pf = null; 123 char line[1024] = {0}, vtemp[1024] = {0}; 124 125 pf = fopen(filename, "r"); //以只读方式打开 126 127 while(!feof(pf)){ 128 fgets(line, 1024, pf); 129 getvalue(line, key, vtemp); 130 if(strlen(vtemp) != 0) 131 break; 132 } 133 if(strlen(vtemp) != 0){ 134 *value = (char *)malloc(sizeof(char) * strlen(vtemp) + 1); 135 strcpy(*value, vtemp); 136 } 137 else 138 *value = null; 139 if(pf != null) 140 fclose(pf); 141 }
测试:
1 #define filename "c:/cfg.ini" 2 void menu(){ 3 printf("===========================\n"); 4 printf("1 写入配置文件\n"); 5 printf("2 读取配置文件\n"); 6 printf("0 退出程序"); 7 printf("===========================\n"); 8 } 9 10 int twrite(){ 11 12 char key[1024] = {0}, value[1024] = {0}; 13 14 printf("请输入key:"); 15 scanf("%s", key); 16 printf("请输入value:"); 17 scanf("%s", value); 18 printf("\n您输入的是:%s = %s\n", key, value); 19 20 return writecfg(filename/*in*/,key/*in*/,value/*in*/); 21 } 22 23 void tread(){ 24 char key[1024] = {0}, *value; 25 26 printf("请输入key:"); 27 scanf("%s", key); 28 29 readcfg(filename/*in*/,key/*in*/, &value/*out*/); 30 if(value == null){ 31 printf("没有key\n"); 32 return ; 33 } 34 printf("\nvalue = %s\n", value); 35 36 if(value != null){ 37 free(value); 38 value = null; 39 } 40 41 } 42 int main(){ 43 44 int choose; 45 46 while(1){ 47 choose = 0; 48 menu(); 49 printf("请输入选择:"); 50 scanf("%d", &choose); 51 switch(choose){ 52 case 1: 53 if(twrite() == -1) 54 return -1; 55 break; 56 case 2: 57 tread(); 58 break; 59 case 0: 60 return 0; 61 default: 62 return 0; 63 } 64 } 65 system("pause"); 66 return 0; 67 }
运行结果: