Highlight words in richtextbox

[poe]

Hello, I have a rich text box with some text in it.

I would like to highlight "the next" word when i click a button.

Say that my text is this:
Once upon a time

Then when i click the button i want "Once" to get highlighted. Then when i click the button again, i want "upon" to get highlighted, and then the next word and the next word.

Is this possible?
Thanks.

 

[JohnH]

Try this:

    Dim word, index As Integer
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) _
    Handles Button1.Click
        RichTextBox1.HideSelection = False
        Dim text As String = RichTextBox1.Text.Replace(vbLf, " ")
        Dim words() As String = text[SIZE=2].Split([/SIZE][SIZE=2][COLOR=#a31515]" "[/COLOR][/SIZE][SIZE=2].ToCharArray, StringSplitOptions.RemoveEmptyEntries)[/SIZE]
        If word >= words.Length Then
            word = 0
            index = 0
        End If
        index = RichTextBox1.Find(words(word), index, RichTextBoxFinds.None)
        RichTextBox1.Select(index, words(word).Length)
        index += words(word).Length
        word += 1
    End Sub

 

[poe]

Thanks for your reply!

It works until it tries to highlight the last word on the row. Then it crashes and gives:
InvalidArgument=Value of '-1' is not valid for 'start'.

on this line:

RichTextBox1.Select(index, words(word).Length)

I think it has something to do that there isnt a space after the last word, so the last word gets connected to the first word on the next row.

 

[JohnH]

It happened because you had an extra space after the text. I modified the code to handle this, now it also handle possible other occurences of multiple spaces in text.

 

[poe]

Thanks again for your reply. I tried the code but I still get that error.
It crashes on the last word on the row.

The text is on multiple rows. :/

 

[JohnH]

Yes, I guess it is very natural with linebreaks in a RichTexBox, however it is very easy to fix, just remove the linebreaks from the text before breaking up the words. The original code is modified to handle also linebreaks now.

 

[poe]

Thanks, it works perfectly now!