C语言 文件的读写操作

 //凯鲁嘎吉 - 博客园 http://www.cnblogs.com/kailugaji/

#include<stdio.h>
#include<stdlib.h>
void main(){
    int a;
    void write();
    void read();
    while(1){
        printf("*****************
");
        printf("1.write
");
        printf("2.read
");
        printf("0.exit
");
        printf("*****************
");
        printf("Please choose:");
        scanf("%d",&a);
        if(a==0){
            exit(0);
        }
        else if(a==1){
            write();
        }
        else if(a==2){
            read();
        }
        else
            printf("input error!
Please choose:");
    }  
    
}

void write(){
    FILE *fp;
    char ch,filename[20];
    printf("Please input the filename you want to write:");
    scanf("%s",filename);
    if(!(fp=fopen(filename,"wt+"))){
        printf("Cannot open the file!
");
        exit(0);
    }
    
    printf("Please input the sentences you want to write:");
    ch=getchar();
    ch=getchar();
    while(ch!=EOF){  //EOF: Ctrl+z
        fputc(ch,fp);
        ch=getchar();
    }
    
    fclose(fp);
    
}

void read(){
    FILE *fp;
    char ch,filename[20];
    printf("Please input the filename you want to read:");
    scanf("%s",filename);
    if(!(fp=fopen(filename,"r"))){
        printf("Cannot open the file!
");
        exit(0);
    }
    
    printf("%s 的内容为:",filename);
    while(ch!=EOF){  //EOF(end of file): Ctrl+z
        ch=fgetc(fp);
        putchar(ch);
    }
    
    fclose(fp);
}

程序运行前的当前目录：

程序运行结果：

当前目录多了一个文件wrr.txt

打开该文件：

 

里面已经有了刚刚输入的内容：

Hello world!
I am RONGRONG WANG!
My English name is Kailugaji!
Thank you!