Firstly open the file using fopen
:
FILE* fp = fopen("NAME_OF_FILE.txt", "r"); // "r" stands for reading
Now, check if it opened
if(fp == NULL) //If fopen failed
{
printf("fopen failed to open the file\n");
exit(-1); //Exit program
}
Suppose that these are your arrays to store the line and each data are:
char line[2048]; //To store the each line
char itemCode[50];
char item[50];
double price;
int quantity; //Variables to store data
Read the file using fgets
. It consumes line by line. Put it in a loop which terminates when fgets
returns NULL
to scan the whole file line by line. Then extract data from the scanned line using sscanf
. It, in this case, will return 4 if successful:
while(fgets(line, sizeof(line), fp) != NULL) //while fgets does not fail to scan a line
{
if(sscanf(line, "%[^;];%[^;];%lf;%d", itemCode, item, price, quantity) != 4) //If sscanf failed to scan everything from the scanned line
//%[^;] scans everything until a ';'
//%lf scans a double
//%d scans an int
//Better to use `"%49[^;];%49[^;];%lf;%d"` to prevent buffer overflows
{
printf("Bad line detected\n");
exit(-1); //Exit the program
}
printf("ItemCode=%s\n", itemCode);
printf("Item=%s\n", item);
printf("price=%f\n", price);
printf("Quantity=%d\n\n", quantity); //Print scanned items
}
Finally, close the file using fclose
:
fclose(fp);