fread fwrite写文件流

#include <stdio.h>

void main()
{
FILE *fp;
int i;
char array[] = "1234556789";
//////////////////////////////////////////////////////////////////////////
//Write Data to File
// fp=fopen ("student.dat", "w+");
//
// if (fwrite (&array[0], sizeof (array), 1, fp) != 1)
// printf ("file write error\n");
//
// fclose(fp);

//////////////////////////////////////////////////////////////////////////
//Read data from File
if ((fp=fopen("student_upt.dat","r+"))==NULL)
{
printf("cannot open this file\n");
return ;
}

fseek(fp, 0L, 2);
long FileSize = ftell(fp);

char *ptrArray = new char[FileSize];

if (ptrArray == NULL)
{
return;
}

fseek(fp, 0L, 0);
fread(&array[0], sizeof (array), 1, fp);

for (i = 0; i < sizeof(array); i++)
{
printf("%c ", array[i]);
}

printf("\n");

fseek(fp, 0L, 0);
fread(ptrArray, (size_t)FileSize, 1, fp);

for (i = 0; i < FileSize; i++)
{
printf("%c", ptrArray[i]);
}

printf("\n");

fclose(fp);

//////////////////////////////////////////////////////////////////////////
//Write Data to File
fp=fopen ("student.dat", "w+");

if (fwrite (ptrArray, (size_t)FileSize, 1, fp) != 1)
{
printf ("file write error\n");
}

delete []ptrArray;
ptrArray = NULL;
fclose(fp);
}