如何在混合了Strings和Integer的文本文件中获得INTEGER？

Question

I'm trying to get an int value from a text file. This is my current read file algorithm:

if (q) 
{
    while ((ch = fgetc(q)) != EOF)
    {
        if(ch == )
            printf("%c",ch);
    }
}
else
{
    printf("Failed to open the file\n");
}

Inside my text-file:

Occupant's Name: qwe qwe
Room Number: 1
Occupant's Category: Superior Double

Occupant's Name: h j
Room Number: 1
Occupant's Category: Superior Double

Occupant's Name: h j
Room Number: 1
Occupant's Category: Superior Double

I would like to get every room number.

Answer 1

Consider using fgets to read each line and sscanf to parse the line. This sscanf will fail on the lines that do not start with "Room Number:".

char line[100] = "";
int room = 0;
if (q) 
{
    while (( fgets ( line, sizeof line, q)))
    {
        if( ( sscanf ( line, "Room Number:%d", &room)) == 1) {
            printf("room number is %d\n", room);
        }
    }
}
else
{
    printf("Failed to open the file\n");
}