C, c + + file operations-file data read

Ways to read data from a file

const char * filename = "c:/abc.txt";

FILE * fp = fopen (filename, "RB");

if (fp = = NULL)

{

printf ("Open file failed!") \ n ");

return-1;

}

Mode selection is "RB" (read binary)

Reading data

size_t fread (void * buf,

size_t size,

size_t Nelem,//maximum number of bytes read

FILE * FP

)

Returns the number of bytes read to a file

Sequential read

#include <stdio.h>#include<string.h>intMain () {//Define file name    Const Char* filename ="C:/aaa.txt"; //Open the file, the system will create a file based on the specified path and file nameFILE * fp = fopen (filename,"RB"); //Determines whether the file pointer is empty to determine whether the file was created successfully    if(fp = =NULL) {printf ("failed to open file!\n"); return-1; }     Charbuf[4];  while(!feof (FP)) {         intn = fread (buf,1,4, FP); if(n>0) {printf ("read%d bytes \ n", N);        }} fclose (FP); return 0;}

C, c + + file operations-file data read