我有两个文件，如下所示：
文件 A 是：
J5
J15
J25
J30
J35
文件 B 是：
J0 23 56
J5 24 58
J10 26 60
J15 29 63
J20 31 36
J25 23 32
J30 51 14
J35 34 21
J40 46 12
问题是我必须检查 FILE A 和 FILE B 的内容，并将 Jth 项的值复制到一个新文件中，如下所示：（文件 C）：
J5 24 58
J15 29 63
J25 23 32
J30 51 14
J35 34 21
如果你制定一个 C 代码来解决这个问题，那将是非常有帮助的。谢谢。
我建议您制作三个“随机访问文件”（因为它们更有条理），但首先：
[1]
/* Struct for the first file. */
typedef {
char name[4];
} file1_t;
[2]
/* Struct for the second file. */
typedef {
char name[4];
int value1, value2;
} file2_t;
要创建这些文件，您必须使用这样的代码（假设文件以“wb”模式打开，但未创建）：
/* This is an incomplete example (I can't make your whole Homework)*/
void file2Creator( FILE *fPtr )
{
int i; // Counter to create the file.
file2_t data = { "", 0, 0 }; // A blank example to format the file.
/* You will create 9 consecutive records*/
for( i = 1; i <= 9; i++ ){
fwrite( &data, sizeof( file2_t ), 1, fPtr );
}
fclose( fPtr ); // You can close the file here or later however you need.
}
之后，您必须填写您所做的空白（我想文件已打开）：
void fillFile2( FILE *fPtr)
{
int position;
file2_t data = { "", 0, 0 };
printf( "Enter the position to fill (1-9) 0 to finish:\n?" );
scanf( "%d", &position );
while( position != 0 ){
printf( "Enter the name, and the two other values (integers):\n?" );
fscanf( stdin, "%s%d%d", data.name, data.value1, data.value2 );
/* You have to seek the pointer. */
fseek( fPtr, ( position - 1 ) * sizeof( file2_t ), SEEK_SET );
fwrite( &data, sizeof( file2_t ), 1, fPtr );
printf( "Enter a new position (1-9) 0 to finish:\n?" );
scanf( "%d", &position );
}
fclose( fPtr ); //You can close the file or not, depends in what you need.
}
现在我想象你已经格式化了文件1，文件2和文件3，并且文件1和2都被填充了，你想填充文件3怎么做呢？简单的。
/* 3 pointers to each file */
void fillFile3( FILE *f1Ptr, FILE *f2Ptr, FILE *f3Ptr )
{
int i, j, k, number;
char word[ 4 ];
file1_t data1 = { "" };
file2_t data2, data3 = { "", 0, 0 };
k = 1;
/* I suppose that files are opened with their correctly FILE pointers. */
for( i = 1; i <= 5; i++ ){
/* I locate in the "i" position of the file1. */
fseek( f1Ptr, ( i - 1 ) * sizeof( file1_t ), SEEK_SET );
/* I read the slot. */
fread( &data1, sizeof( file1_t ), 1, f1Ptr );
/*Now we compare the file2 until we find the correct value, if it is organized we can jump some slots if not compare with all.*/
for( j = 1; j <= 9, j++ ){
fseek( f2Ptr, ( j - 1 ) * sizeof( file2_t ), SEEK_SET );
fread( &data2, sizeof( file2_t ), 1, f2Ptr );
/* We compare the strings, If they are equal we paste the value in file 3*/
if( strcmp( data1.name, data2.name ) == 0 ){
/*file 3 is of type of the file 2*/
fseek( f3Ptr, ( k - 1 ) * sizeof( file2_t ), SEEK_SET );
fwrite( &data2, sizeof( file2_t ), 1, f3Ptr );
k++;
break;
}
}
}
fclose( f1Ptr );
fclose( f2Ptr );
fclose( f3Ptr );
}
我正在尝试执行此程序，但它无法运行。
#include <stdio.h>
#include <stdlib.h>
int main()
{
FILE *fp1 ,*fp2;
char ca , cb;
int i,j,x,s;
char A[i][j],B[i][j];
char file1[1024], file2[1024];
printf( "Enter file1: ", file1 );
gets( file1 );
printf( "Enter file2: ",file2 );
gets( file2 );
fp1=fopen( file1, "r");
if ( fp1 == NULL ){
printf("Cannot open %s for reading \n", file1 );
exit(1);
}
while ( ( fgets( file1, sizeof file1, stdin ) ) != EOF ){
for(i=0;i<2500;i++){
for(j=0;j<5;j++){
fscanf(fp1,"%s",&A[i][j]);
}
}
}
fp2 = fopen( file2, "r");
if ( fp2 == NULL ){
printf("Cannot open %s for reading \n", file2 );
exit( 1 );
}
while ( fgets ( file2, sizeof file2, stdin) != EOF){
for( i = 0; i < 2500; i++ ){
for( j = 0; j < 5; j++ ){
fscanf(fp2,"%s",&B[i][j]);
}
}
}
/*Here it was a ; without any sense (after the if)*/
if( strcmp( A[i][j], B[i][j] ) ) == 0;
{
printf( "%s /n %s ", strcmp( A[i][j], B[i][j] ) );
}
fclose(fp1);
fclose(fp2);
return 0;
}
编译器在“==”标记之前显示语法错误（strcmp 函数底部的第 8 行）。有什么帮助吗？？
你在 if 后面加了一个分号，却忘记了括号。
if( strcmp( A[i][j], B[i][j] ) == 0 ){
printf( "%s /n %s ", strcmp( A[i][j], B[i][j] ) );
}