为什么C中的linecount没有工作？

Question

I'm trying to read a text file but before that I want to know how many elements I'm going to read. So I need to count the lines of a text file. So far, I have this:

int getLinecount (char *file) 
{
    int ch, count = 0;
    FILE *fp = fopen(file, "r");
    if(fp == NULL)
    {
        return -1;
    }
    while((ch = fgetc(fp)) != EOF)
    {
        if (ch == '\n'); 
        {
            count++;
        }
    }
    fclose(fp);
    return count;
}

This worked pretty fine. I have changed nothing about the text file and still it prints 130,000 though the file only has 10,000 lines. The only thing I wrote in my main is:

linecount = getLinecount("...");

I am really curious where the error is. Also, is there a better option of getting the linecount?

Answer 1

You have a trailing semicolon ; after your if statement. Then, the block is always executed:

{
    count++;
}

Answer 2

Change

if (ch == '\n'); 

to:

if (ch == '\n')

Answer 3

Trailing semi-colon after the if : remove it. With the trailing semi-colon the code is equivalent to:

if (ch == '\n') {}
count++;

meaning that count is incremented for every iteration of the loop (every char in the file).

Answer 4

you have trailing semicolon to delete after if

and for reading files, better use this code :

while((fgets(blahblahblah)) != NULL) {
  counter++;
}

Answer 5

一切都很好，除了分号（ ; ），应该从行中删除

if (ch == '\n')

Answer 6

Apart from the ; issue mentioned by others, an alternative solution can be found in this post as he explains why he does things the way he does.

Answer 7

You might want to consider the OS you are using to create and view this file.

Copied from PHP Echo Line Breaks :

• '\\n' is a linux/unix line break
• '\\r' is a classic mac line break [OS X uses the above unix \\n]
• '\\r'+'\\n' is a windows line break