求教文件的成块读写函数fwrite和fread

[chenzuzhang]

运行结果，输出显示没有问题，但是文件employee.txt中却是乱码：zhang3 烫烫烫烫烫烫? m烫蘬i4 烫烫烫烫烫烫烫烫# m烫


#include<stdio.h>
#include<string.h>
#define MAX_EMPLOYEE 100
struct Person
{
char m_strName[20]; //人员姓名
int m_nAge; //人员年龄
char m_nSex; //人员性别
};
struct Person Register(char *name,int age,char sex)
{
struct Person x;
strcpy(x.m_strName,name);
x.m_nAge=age;
x.m_nSex=((sex=='m')?'m':'f');
return x;
}
void ShowPerson(struct Person x)
{
printf("\n%s %d %c\n",x.m_strName,x.m_nAge,x.m_nSex);
}
int WriteRecord(FILE *file,struct Person *emp)
{
return fwrite(emp,sizeof(struct Person),1,file);
}
int ReadRecord(FILE *file,struct Person *emp)
{
return fread(emp,sizeof(struct Person),1,file);
}
void main()
{
struct Person personlist[MAX_EMPLOYEE],x;
int count=0;
int i;
FILE *emp_file;
personlist[count]=Register("zhang3",32,'m');
ShowPerson(personlist[count]);
count++;
personlist[count]=Register("li4",35,'m');
ShowPerson(personlist[count]);
count++;
emp_file=fopen("employee.txt","wt");
if(!emp_file)
{
printf("Error open file!\n");
return ;
}
for(i=0;i<count;i++)
WriteRecord(emp_file,&(personlist[i]));
fclose(emp_file);
emp_file=fopen("employee.txt","rt");
if(!emp_file)
{
printf("Error open file!\n");
return ;
}
ReadRecord(emp_file,&x);
ShowPerson(x);
fclose(emp_file);
}

[ProgrammingRing]

用十六进制工具，如WinHEX打开那文件看下你就知道了

[ProgrammingRing]

fwrite是二进制写入的

[ls176]

#include<stdio.h>
#include<string.h>

#define MAX_EMPLOYEE 100


typedef struct person
{
	char m_strName[20]; //人员姓名
	int  m_nAge;        //人员年龄
	char m_nSex;        //人员性别
} Person;

Person Register( char *name , int age , char sex )
{
	Person x;
	strcpy( x.m_strName , name );
	x.m_nAge = age;
	x.m_nSex = ( ( sex == 'm' ) ? 'm' : 'f' );
	return x;
}

void ShowPerson( Person x )
{
	printf( "\n%s %d %c\n" , x.m_strName , x.m_nAge , x.m_nSex );
}

int WriteRecord( FILE *file , Person *emp )
{
	//return fwrite( emp , sizeof( Person ) , 1 , file );
	char row[ sizeof( Person ) ];
	sprintf( row , "%s %d %c\n" , emp->m_strName , emp->m_nAge , emp->m_nSex );
	return fputs( row , file );
}

int ReadRecord( FILE *file , Person *emp )
{
	//return fread( emp , sizeof( Person ) , 1 , file );
	char row[ sizeof( Person ) ];
	fgets( row , sizeof( Person ) , file );
	strcpy( emp->m_strName , strtok( row  , " " ) );
	emp->m_nAge = atoi( strtok( NULL  , " " ) );
	emp->m_nSex = strtok( NULL  , " " )[0];
	return 0;
}

void main()
{
	Person personlist[MAX_EMPLOYEE] , x;
	int count = 0;
	int i;
	FILE *emp_file;

	personlist[ count ] = Register( "zhang3" , 32 , 'm' );
	ShowPerson( personlist[ count ] );
	count++;
	personlist[ count ] = Register( "li4" , 35 , 'm' );
	ShowPerson( personlist[ count ] );
	count++;

	emp_file=fopen( "employee.txt" , "wt" );
	if( !emp_file )
	{
		printf( "Error open file!\n" );
		return ;
	}
	for( i = 0 ; i < count ; i++ )
	{
		WriteRecord( emp_file , &personlist[i] );
	}
	fclose( emp_file );

	emp_file = fopen( "employee.txt" , "rt" );
	if( !emp_file )
	{
		printf( "Error open file!\n" );
		return ;
	}
	ReadRecord( emp_file , &x );
	ShowPerson( x );
	fclose( emp_file );
}

改了下代码，改成读取字符串方式的了，这样文本文件中的内容就不是乱码了。
LZ如果是想成块保存结构（也就是序列化），那文件中就肯定是乱码。
如果想内容不是乱码，就按文本方式读取保存就可以了。

[自信男孩]

感觉还是用fscanf()和fprintf()进行文件读写比较好。

[chenzuzhang]

谢谢，我是新手，字符串读写学会了，想学一下成块读写，请大侠指教！[Quote=引用 3 楼 ls176 的回复:]
C/C++ code


#include<stdio.h>
#include<string.h>

#define MAX_EMPLOYEE 100


typedef struct person
{
char m_strName[20]; //人员姓名
int m_nAge; //人员年龄
char m_nSex; ……
[/Quote]