C语言 fscanf 和 fprintf函数示例详解

  int __cdecl fprintf(FILE * __restrict__ _File,const char * __restrict__ _Format,...);
  int __cdecl printf(const char * __restrict__ _Format,...);
  int __cdecl sprintf(char * __restrict__ _Dest,const char * __restrict__ _Format,...) __MINGW_ATTRIB_DEPRECATED_SEC_WARN;
  int __cdecl vfprintf(FILE * __restrict__ _File,const char * __restrict__ _Format,va_list _ArgList);
  int __cdecl vprintf(const char * __restrict__ _Format,va_list _ArgList);
  int __cdecl vsprintf(char * __restrict__ _Dest,const char * __restrict__ _Format,va_list _Args) __MINGW_ATTRIB_DEPRECATED_SEC_WARN;
  int __cdecl fscanf(FILE * __restrict__ _File,const char * __restrict__ _Format,...) __MINGW_ATTRIB_DEPRECATED_SEC_WARN;
  int __cdecl scanf(const char * __restrict__ _Format,...) __MINGW_ATTRIB_DEPRECATED_SEC_WARN;
  int __cdecl sscanf(const char * __restrict__ _Src,const char * __restrict__ _Format,...) __MINGW_ATTRIB_DEPRECATED_SEC_WARN;

#include <stdio.h>
#include <stdlib.h>
#include "file.h"
/* run this program using the console pauser or add your own getch, system("pause") or input loop */
int main(int argc, char *argv[]) {
	writeTest(1000);
	readData(1000);
	return 0;
}

#include "file.h"
void writeTest(int data)
{
	FILE *fp1,*fp2;
	double r1,r2;
	int i;
	srand((unsigned)time(NULL)); 
	//若为空则退出 
	if((fp1=fopen("D:\\in1.txt","w"))==NULL)
	{
		printf("can not open the in file\n");
		exit(0);
	}
	if((fp2=fopen("D:\\out1.txt","w"))==NULL)
	{
		printf("can not open the out file\n");
		exit(0);
	}
//RAND_MAX 32767 rand()%1000——0到 999 之间的整数（包含 0 和 999）
//rand()%1000/100为0-9.99浮点数 
	for(i=0;i<data;i++)
	{
		r1=rand()%1000/100.0;
		r2=rand()%1000/100.0;
		fprintf(fp1,"%lf  %lf\n",r1,r2);
		fprintf(fp2,"%lf \n",r1+r2);
	}
	fclose(fp1);
	fclose(fp2);
}
void readData(int data)
{
	FILE *fp1,*fp2;
	int i,j;
	double arr[10];//定义一个字符型数组去存
	if((fp1=fopen("D:\\in1.txt","r"))==NULL){
		printf("can not open the in file\n");
		exit(0);
	}
	for(i=0;i<data;i++)
		for(j=0; j<2; j++)
			fscanf(fp1,"%lf ",&arr[0]);//赋值于字符型数组中的元素值 
				printf("%lf \n",arr[0]);//在终端中打印输出 
	fclose(fp1);
	if((fp2=fopen("D:\\out1.txt","r"))==NULL){
		printf("can not open the out file\n");
		exit(0);
	}
	for(i=0;i<data;i++)
		for(j=0; j<1; j++)
			fscanf(fp2,"%lf",&arr[1]);
			printf("%lf",arr[1]);//在终端中打印输出 
	fclose(fp2);
}

#ifndef __FILE_H
#define __FILE_H
#include <stdio.h>
#include <stdlib.h>
#include "math.h"
typedef unsigned char uint8;
#endif