计算文件的总字符数

Question

Hi I'm pretty new to C# and trying to do some exercises to get up to speed with it. I'm trying to count the total number of characters in a file but it's stopping after the first word, would someone be able to tell me where I am going wrong? Thanks in advance

 public void TotalCharacterCount()
        {
            string str;
            int count, i, l;
            count  = i = 0;

            StreamReader reader = File.OpenText("C:\\Users\\Lewis\\file.txt");
            str = reader.ReadLine();
            l = str.Length;


                while (str != null && i < l)
                {

                    count++;

                    i++;

                    str = reader.ReadLine();
                }



            reader.Close();
            Console.Write("Number of characters in the file is : {0}\n", count);


        }

Answer 1

If you want to know the size of a file:

long length = new System.IO.FileInfo("C:\\Users\\Lewis\\file.txt").Length;
Console.Write($"Number of characters in the file is : {length}");

If you want to count characters to play around with C#, then here is some sample code that might help you

            int totalCharacters = 0;

            // Using will do the reader.Close for you. 
            using (StreamReader reader = File.OpenText("C:\\Users\\Lewis\\file.txt"))
            {
                string str = reader.ReadLine();

                while (str != null)
                {
                    totalCharacters += str.Length;
                    str = reader.ReadLine();
                }
            }

            // If you add the $ in front of the string, then you can interpolate expressions 
            Console.Write($"Number of characters in the file is : {totalCharacters}");

Answer 2

it's stopping after the first word

It is because you have check && i < l in the loop and then increment it so the check doesn't pass you don't change the value of l variable(by the way, the name is not very good, I was sure it was 1 , not l ).

Then if you need to get total count of characters in the file you could read the whole file to a string variable and just get it from Count() Length

var count = File.ReadAllText(path).Count();

Getting Length property of the FileInfo will give the size, in bytes, of the current file , which is not necessary will be equal to characters count(depending on Encoding a character may take more than a byte)

And regarding the way you read - it also depends whether you want to count new line symbols and others or not.

Consider the following sample

static void Main(string[] args)
{
    var sampleWithEndLine = "a\r\n";
    var length1 = "a".Length;
    var length2 = sampleWithEndLine.Length;
    var length3 = @"a
".Length;

    Console.WriteLine($"First sample: {length1}");
    Console.WriteLine($"Second sample: {length2}");
    Console.WriteLine($"Third sample: {length3}");
    var totalCharacters = 0;
    File.WriteAllText("sample.txt", sampleWithEndLine);

    using(var reader = File.OpenText("sample.txt"))
    {
        string str = reader.ReadLine();

        while (str != null)
        {
            totalCharacters += str.Length;
            str = reader.ReadLine();
        }
    }

    Console.WriteLine($"Second sample read with stream reader: {totalCharacters}");

    Console.ReadKey();
}

For the second sample, first, the Length will return 3, because it actually contains three symbols, while with stream reader you will get 1, because The string that is returned does not contain the terminating carriage return or line feed. The returned value is null if the end of the input stream is reached