我如何从文件中读取结构？

Question

struct Country{
    char name[50];
    float square;
    float quantityOfPeople;
};

 while (fread(&newRecord,sizeof(struct Country),1,fout)) {
        printf("hello\n");
        if (strcmp (countryName, newRecord.name) == 0) {
            printf("A record with requested name found and deleted.\n\n");
            found=1;
        } else {
            fwrite(&newRecord, sizeof(struct Country), 1, fp_tmp);
        }

    }

my file is

hjk
78.699997
799.900024

america
3432.300049
2323.199951

ghi
78.900002
89.000000

dmdmd
746234052608.000000
0.000000

In my file there is 4 records of country so it should print 4 times hellp, but it prints hello twice. The main task is to remove the duplicate entry in the file.

Answer 1

fread(&newRecord,sizeof(struct Country),1,fout) is for reading binary data from a file.

OP's file is text based.

---

How can i read struct from a file?

Open the file in text mode.

Form a helper function that reads 4 lines with 4x fgets() and then processes the lines for 1) country name, 2) some double (see strod() ) 3) another double and 4) an optional empty line.

If all these pass, save in a struct Country

Return 1 for success, 0 for failure, EOF for nothing read.