问题
I'm writing a function that reads the number of lines in the given line. Some text files may not end with a newline character.
int line_count(const char *filename)
{
int ch = 0;
int count = 0;
FILE *fileHandle;
if ((fileHandle = fopen(filename, "r")) == NULL) {
return -1;
}
do {
ch = fgetc(fileHandle);
if ( ch == '\n')
count++;
} while (ch != EOF);
fclose(fileHandle);
return count;
}
Now the function doesn't count the number of lines correctly, but I can't figure out where the problem is. I would be really grateful for your help.
回答1:
fgets()
reads till newline character or till the buffer is full
char buf[200];
while(fgets(buf,sizeof(buf),fileHandle) != NULL)
{
count++;
}
fgetc()
is an issue here because you encounter EOF
first and exit your do while
loop and never encounter a \n
character so count remains untouched for the last line in your file.If it happens to be there is a single line in your file that the count
will be 0
回答2:
Here is another option (other than keeping track of last character before EOF).
int ch;
int charsOnCurrentLine = 0;
while ((ch = fgetc(fileHandle)) != EOF) {
if (ch == '\n') {
count++;
charsOnCurrentLine = 0;
} else {
charsOnCurrentLine++;
}
}
if (charsOnCurrentLine > 0) {
count++;
}
来源:https://stackoverflow.com/questions/29751837/counting-number-of-lines-in-the-file-in-c