How to read the content of txt file in c language?

In C language, file operations are completed by library functions.

Recommendation: "c Language Tutorial"

To read a txt file, first use the file opening function fopen().

The fopen function is used to open a file. The general form of its call is: file pointer name = fopen (file name, using file mode). Among them, the "file pointer name" must be a pointer specified as a FILE type. Variable, "filename" is the file name of the opened file. "Use file method" refers to the type of file and operation requirements. "filename" is a string constant or an array of strings.

Secondly, use the file read and write functions to read the file.

Provides a variety of file reading and writing functions in C language:

·Character reading and writing functions: fgetc and fputc

·String reading and writing functions: fgets and fputs

·Data block read and write functions: freed and fwrite

·Format read and write functions: fscanf and fprinf

Finally, use file close at the end of file reading The function fclose() closes the file.

Example:

#include <stdio.h>
#include <stdlib.h>
#include  <assert.h>
typedef struct student{
        char name[32];
        int  no;
        char sex[16];
        float score;
} stu;
 
int main(int argc, char* argv[])
{
    //打开文件 
    FILE * r=fopen("A.txt","r");
    assert(r!=NULL);
    FILE * w=fopen("B.txt","w");
    assert(w!=NULL);
     
    //读写文件 
    stu a[128];
    int i=0;
    while(fscanf(r,"%s%d%s%f",a[i].name,&a[i].no,a[i].sex,&a[i].score)!=EOF)
    {
         printf("%s\t%d\t%s\t%g\n",a[i].name,a[i].no,a[i].sex,a[i].score);//输出到显示器屏幕 
         fprintf(w,"%s\t%d\t%s\t%g\n",a[i].name,a[i].no,a[i].sex,a[i].score);//输出到文件B.txt 
         i++;
    }  
     
    //关闭文件 
    fclose(r);
    fclose(w);
     
    system("pause");
    return 0;
}

The result after compilation and running is as follows:

programming introduction column!

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