How to count characters in c# from a richtextbox

Question

Ok so basically what I am trying to accomplish here is to count all of the characters in the richtextbox and show which of them are the vowels and it will constantly update and show the number of chars/vowels in the toolstrip bar. Pretty straightforward code but there seems to be some errors in the foreach loop and the textchanged. Would appreciate some feedback please :)

private void Form1_Load(object sender, EventArgs e)
{
    int vowels;
    int characters;
    foreach(int char in rtbDoc)
    {
        characters+=1;
    }
    if (rtbDoc.Text == "a".ToLower() || rtbDoc.Text == "e".ToLower() 
        || rtbDoc.Text == "i".ToLower() || rtbDoc.Text == "o".ToLower()
        || rtbDoc.Text == "u".ToLower())
    {
        vowels += 1;
    }

    toolStripStatusLabel1.TextChanged = characters + 
                      "Characters, of which " + vowels + " are vowels";
}

You are doing a .ToLower() on the static value. This should be done on the rtbDoc.Text. — UnhandledExcepSean, Apr 15 '16 at 13:28
Shouldn't the `if` be inside the loop and also check the char? — Magnus, Apr 15 '16 at 13:31
Your `IF` is outside the foreach, your foreach is using the control and not rtbDoc.Text. — Prix, Apr 15 '16 at 13:31
Why you put this into Form_load? Use appropriate event from your textbox. — Andrey Ischencko, Apr 15 '16 at 13:32
Yes you are correct. I just put the if statement in the foreach instead of leaving it out. I'm still learning c# and am quite new to it. thanks for this! :) — Cyanic Wolf, Apr 15 '16 at 13:47
I used the formload since I didn't really need a trigger function here and it works out well there — Cyanic Wolf, Apr 15 '16 at 13:49
Thank you all for your feedback. I'm sure that this question and the answers you people provided me with will be of help to others — Cyanic Wolf, Apr 15 '16 at 14:19

fubo · Accepted Answer · 2016-04-15T13:41:22.247

7

Here is a Linq approach

char[] Vowels = new char[] { 'a', 'e', 'i', 'o', 'u' };
int CharacterCount = rtbDoc.Text.Length;
int VowelCount = rtbDoc.Text.Count(x => Vowels.Any(y => char.ToLower(x) == y));

edited Apr 15 '16 at 13:41

answered Apr 15 '16 at 13:33

fubo

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Related to make it work with non ASCII characters: http://stackoverflow.com/a/35088029/1207195 (and any other language which is not en-US). Side note: you can directly use .Count(x => ...) instead of .Where(x => ...).Count() – Adriano Repetti Apr 15 '16 at 13:34
1

Sacrificing readability for terseness - `int VowelCount = text.ToLower().Count(Vowels.Contains);` – stuartd Apr 15 '16 at 13:46
And for everyone else thinking about, for example, Turkish language: **do not ever use ToLower()** in your code. 99.9% it's the wrong pick. Use a culture aware StringComparer, always. – Adriano Repetti Apr 15 '16 at 13:56

Dmitry Bychenko · Answer 2 · 2016-04-15T13:49:46.617

2

First I suggest extracting a method:

private static bool IsVowel(Char value) {
  //TODO: is 'y' a vowel?
  return 
    value == 'a' || value == 'i' || value == 'e' || value == 'o' || value == 'u' ||
    value == 'A' || value == 'I' || value == 'E' || value == 'O' || value == 'U';
}

Then using Linq:

//TODO: do you really want to compute vowels count on Form Load? Not on rtbDoc.TextChanged?
private void Form1_Load(object sender, EventArgs e) {
  String text = rtbDoc.Text;

  // Finally, formatting which is more readable
  //DONE: you've probably want to assign to Text, not to TextChanged
  toolStripStatusLabel1.Text = 
    String.Format("{0} Characters, of which {1} are vowels.", 
                  text.Length,
                  text.Count(c => IsVowel(c)));
}

edited Apr 15 '16 at 13:49

answered Apr 15 '16 at 13:36

Dmitry Bychenko

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@fubo: well, `text.Count(IsVowel)` is *shorter*, but, IMHO, `Count(c => IsVowel(c))` is more readable. – Dmitry Bychenko Apr 15 '16 at 13:40
`toolStripStatusLabel1.TextChanged` – Prix Apr 15 '16 at 13:44
1

@Prix: thank you! Copy + Paste from a question is a *bad* thing. – Dmitry Bychenko Apr 15 '16 at 13:51

score 0 · Answer 3 · answered Apr 15 '16 at 13:40

You have to check each char if it is a vowel

private void Form1_Load(object sender, EventArgs e)
{
  char[] vowelSet = { 'a', 'e', 'i', 'o', 'u' };
  int vowels = 0;
  int characters = 0;
  foreach(char c in rtbDoc.Text.ToLower())
  {
    characters+=1;

    if (vowelSet.Contains(c))
    {
        vowels += 1;
    }
  }

  toolStripStatusLabel1.TextChanged = characters + 
                      "Characters, of which " + vowels + " are vowels";
}

To Update the label after changes, you have to use TextChanged event of the RichTextBox

score -1 · Answer 4 · answered Apr 15 '16 at 13:37

Your code should be this way if you want it to update every time it changes

 // you code should be inside the TextChanged event for the richtextbox to get called everytime the text is modified
    private void rtbDoc_TextChanged(object sender, EventArgs e) {
        int vowels = 0; // you should initialize your variables
        int characters = 0;// you should initialize your variables
        foreach (char c in rtbDoc.Text) { // you can't name a variable " char ", and you should choose rtbDoc.Text
            characters += 1;
            if (c.ToString().ToLower() == "a" || c.ToString().ToLower() == "e" // ToLower() function should be on the input
                || c.ToString().ToLower() == "i" || c.ToString().ToLower() == "o" // you should check the character not the whole text
                || c.ToString().ToLower() == "u") {
                vowels += 1;
            }
        }// the if part should be inside the foreach loop to check every character 

        toolStripStatusLabel1.Text = characters +           // you should use toolStripStatusLabel1.Text 
                          "Characters, of which " + vowels + " are vowels";
    }

score -1 · Answer 5 · answered Apr 15 '16 at 13:39

You're almost there.

Your if statement is saying that if the text in the box IS "a" (or any other vowel character), add one. Otherwise, you don't do anything. Take for example, the input "aeiou". Your if statement will not add one to vowels, then you subscribe to textchanged and you're done. Currently, you aren't looping over the text in the RichTextBox. The Linq approach outlined by fubo works and is much cleaner but going with what you already have what you really should do is:

var characters = rtbDoc.Text.Length;

foreach(var char in rtb.Text.ToLower())
    if(IsVowel(char)) 
         vowel+=1;

I tried using this 1 since it looked simple enough and quite simple but it did not work out for me unfortunately. But thanks for feedback :) — Cyanic Wolf, Apr 15 '16 at 13:46

How to count characters in c# from a richtextbox

5 Answers5