发个从文件中读取身份证号15位升18位的小程序（如果不是唯一字段 还有待完善 请大神指点）
以下代码只是模拟从文本文件中读取每行起始处为15位的身份证号如果文件格式为其它样式则不成立
只为抛砖引玉
希望看到能从dbf3以上版本文件中读取某个字段的15位（自动排除18位）身份证号
并升级成18位身份证号后写入原始dbf文件的C代码
程序代码：
#include <stdio.h>
#include <stdlib.h>
int readNum(int *n, FILE *fp);
void newId(char *id, int *n);
int calc(int *n);
void writeFile(FILE *fn, char *id);
int main(int argc, char *argv[]) {
int n[17] = {0, 0, 0, 0, 0, 0, 1, 9,};
const char s[11] = "10X98765432";
char id[18];
FILE *fp, *fn;
if(argc != 3) exit(EXIT_FAILURE);
fp = fopen(argv[1], "r");
fn = fopen(argv[2], "w+");
if(!fp || !fn) exit(EXIT_FAILURE);
else {
while(!feof(fp)) {
if(readNum(n, fp) == EOF) break;
newId(id, n);
id[17] = s[calc(n)];
writeFile(fn, id);
}
}
fclose(fp);
fclose(fn);
return 0;
}
int readNum(int *n, FILE *fp) {
int i, ch;
for(i = 0; i < 6; i++) fscanf(fp, "%1d", n + i);
for(i = 8; i < 17; i++) fscanf(fp, "%1d", n + i);
while((ch = getc(fp)) != '\n' && ch != EOF);
return ch;
}
void newId(char *id, int *n) {
int i = -1;
while(++i < 17) id[i] = n[i] + '0';
}
int calc(int *n) {
int i = -1, s = 0;
const int m[17] = {7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2};
while(++i < 17) s += n[i] * m[i];
return s % 11;
}
void writeFile(FILE *fn, char *id) {
int i = -1;
while(++i < 18) putc(id[i], fn);
putc('\n', fn);
}
