函数原型: size_t fread( void *buffer, size_t size, size_t count, FILE *stream );
参 数:
1.用于接收数据的地址(指针)(buffer)
2.单个元素的大小(size) :单位是字节而不是位,例如读取一个整型数就是2个字节
3.元素个数(count)
4.提供数据的文件指针(stream)
返回值:成功读取的元素个数
给你一个例子 你看一下
#include
void main( void )
{
FILE *stream;
char list[30];
int i, numread, numwritten;
/* Open file in text mode: */
if( (stream = fopen( "fread.out", "w+t" )) != NULL )
{
for ( i = 0; i < 25; i++ )
list[i] = (char)('z' - i);
/* Write 25 characters to stream */
numwritten = fwrite( list, sizeof( char ), 25, stream );
printf( "Wrote %d items\n", numwritten );
fclose( stream );
}
else
printf( "Problem opening the file\n" );
if( (stream = fopen( "fread.out", "r+t" )) != NULL )
{
/* Attempt to read in 25 characters */
numread = fread( list, sizeof( char ), 25, stream );
printf( "Number of items read = %d\n", numread );
printf( "Contents of buffer = %.25s\n", list );
fclose( stream );
}
else
printf( "File could not be opened\n" );
}
fread的原型见353951452的回答。
我建议可以这样写:
//声明用到的变量
unsigned char fa[3];
unsigned short ret;
unsigned short idx;
//从文件中读取最多两个字节的数据
ret=fread(fa, 1, 2, fp);
//根据返回的读取到的数据数量,按十六进制的方式和相应的ASCII方式打印出来。
for (idx=0;idx
}
printf("\n");
假如你当前目录有个二进制文件abc, 你可一参考下面程序来读它
#include
#include
int main(void)
{
size_t len;
char buf[128];
FILE *fp = fopen("abc", "rb");
fseek(fp, 0, SEEK_END);
len = ftell(fp);
fread(buf, 1, len, fp);
printf("%s", buf);
fclose(fp);
return 0;
}