11.06 标准IO day2

标准IO
​​​​

！1.

#include <myhead.h>
int main(int argc, const char *argv[])
{
	FILE *fp=fopen("./cp1.txt","r");//已创建有文本文件cp1.txt
	if(fp == NULL)
	{
		perror("fopen");
		return -1;
	}
	FILE *fp1=fopen("./cp2.txt","w");
	if(fp1 == NULL)
	{
		perror("fopen");
		return -1;
	}
	char arr;
	while(fscanf(fp,"%c",&arr)!=EOF)
	{
		fprintf(fp1,"%c",arr);
	}
	fclose(fp);
	fclose(fp1);
}

运行:

2.

#include <myhead.h>
int main(int argc, const char *argv[])
{
	FILE *fp= fopen("./cp1.txt","r");
	if(fp == NULL)
	{
		perror("fopen");
		return -1;
	}
	FILE *fp3=fopen("./cp3.txt","w");
	if(fp3 == NULL)
	{
		perror("fopen");
		return -1;
	}
	char txt[1024];
	while((fgets(txt,sizeof(txt),fp))!=NULL)
	{
		fputs(txt,fp3);
		printf("复制成功\n");
	}
	return 0;
}

3.

menu.c

#include "log.h"
int main(int argc, const char *argv[])
{
	int ch;
	while(1)
	{
		printf("\t\t\t1.注册\n");
		printf("\t\t\t2.登录\n");
		printf("\t\t\t0.退出\n");
		printf("请输入你的选择:");
		scanf("%d",&ch);
		getchar();//吸收换行
		switch(ch)
		{
			case 1:
			regist();//注册函数
			break;
			case 2:
			login();//登录函数
			break;
			case 0:
			exit(0);
			break;
			
		}
	}
	
	return 0;
}

log_reg.c

#include"log.h"
int regist()
{
	//输入账户和密码到文件中
	char name[20];
	char code[20];//密码
	printf("请输入注册账户和密码:");
	fgets(name,sizeof(name),stdin);//==scanf(%s,name)
	fgets(code,sizeof(code),stdin);//==scanf(%s,code)
	name[strlen(name)-1]='\0';//把最后的换行转为\0
	code[strlen(code)-1]='\0';//\0为字符串结束标志

	FILE *fp = fopen("./user.txt","w");
	if(fp == NULL)
	{
		perror("fopen");
		return -1;
	}
	fprintf(fp,"%s %s ",name,code);//格式化写入文件
	printf("注册成功\n");
	fclose(fp);//关闭文件
	return 0;
}

int login()
{
	int flag= 0;
	char name[20],dname[20];
	char code[20],dcode[20];//账户密码
	printf("请输入登录账户和密码:");
	fgets(dname,sizeof(dname),stdin);//==scanf(%s,dname)
	fgets(dcode,sizeof(dcode),stdin);//==scanf(%s,dcode)
	dname[strlen(dname)-1]='\0';//把最后的换行转为\0
	dcode[strlen(dcode)-1]='\0';//\0为字符串结束标志

	FILE *fp = fopen("./user.txt","r");
	if(fp == NULL)
	{
		perror("fopen");
		return -1;
	}
	while(1)
	{
		int res = fscanf(fp,"%s %s ",name,code);

		if(res<0)//读取到文件末尾
		{
			break;
		}
		if(strcmp(dname,name)==0&strcmp(dcode,code)==0)
		{
			flag=1;
			printf("登录成功\n");
			break;
		}
	}
	if(flag==0)
	{
		printf("登录失败\n");
	}
	return 0;

}

log.h

#ifndef _LOG_H_
#define _LOG_H_
#include<myhead.h>
int regist();
int login();
#endif

运行：