读/写C中的int二进制文件错误

我在读取/写入C中的二进制文件时遇到错误。问题是： -我使用fwrite将int（例如2）写入文件 -我尝试使用fread从文件中读取此int -当我读到它时，它不是2，而是一些长的数字，例如967899906或207132354或1030372866（总是不同）

我用C写一个二进制文件，如下所示：

FILE * writeFile = fopen("test.bin","wb");

//test int vars
int test1 = 1;
int test2 = 2;
int test3 = 3;

//writing some ints to binary file
fwrite(&test1,1,1, writeFile);
fwrite(&test2,1,1, writeFile);
fwrite(&test3,1,1, writeFile);

fclose(writeFile);

FILE *readFile = fopen("test.bin","rb");
int data;
while(fread(&data,1,1, readFile)==1){
   printf("%d", data); //here it will output some random number
}
fclose(readFile);

然后我从文件中读取如下内容：

FILE * writeFile = fopen("test.bin","wb");

//test int vars
int test1 = 1;
int test2 = 2;
int test3 = 3;

//writing some ints to binary file
fwrite(&test1,1,1, writeFile);
fwrite(&test2,1,1, writeFile);
fwrite(&test3,1,1, writeFile);

fclose(writeFile);

FILE *readFile = fopen("test.bin","rb");
int data;
while(fread(&data,1,1, readFile)==1){
   printf("%d", data); //here it will output some random number
}
fclose(readFile);

作为第二个参数，需要写入数据的大小，因此在您的情况下

sizeof（int）

对fread来说也是一样的

#include <stdio.h>

int main(void)
{
     FILE * writeFile = fopen("test.bin","wb");

     if (writeFile != NULL)
     {
         //test int vars
         int test1 = 1;
         int test2 = 2;
         int test3 = 3;

         //writing some ints to binary file
         fwrite(&test1,sizeof(test1),1, writeFile);
         fwrite(&test2,sizeof(test2),1, writeFile);
         fwrite(&test3,sizeof(test3),1, writeFile);

         fclose(writeFile);
     }
     else
     {
         perror("Error opening file to write: ");
         return 1;
     }


     FILE *readFile = fopen("test.bin","rb");
     if (readFile != NULL)
     {
         int data;
         while(fread(&data,sizeof(data),1, readFile)==1){
            printf("%d\n", data);
         }
         fclose(readFile);
     }
     else
     {
         perror("Error opening file to read: ");
         return 1;
     }

    return 0;
}

---

如果您有一个

0
fwrite（&test1,1,1，writeFile）的范围，那么LPs在这方面是正确的-->
fwrite（&test1，sizeof（test1），1，writeFile）谢谢，但我有意将每个int保存为1字节（最大值为255）。这将产生怎样的影响？事实上，我应该用最简单的方法让那些测试变量更简单