C# how to add more punctuation marks to the String.Contains Method?

Question

This has been asked before in VB (apparently not satisfactory) but not in C#.

I need to add two punctuation marks to my String.Contains method (apart from the already existing "."), namely "!" and "?".

The idea is that the user finishes his/her input with a punctuation mark (i.e period, question mark or exclamation point). If they don't, the input will not be accepted in the text box.

 private void textBox1_TextChanged_1(object sender, EventArgs e)
        {
            
            if (textBox1.Text.Contains("."))
                
            {            
               Task.Delay(200).Wait();
                MessageBox.Show("Thanks for your input!");
            }

            else
            {
                return;
            }

How do I add these two? It seems impossible to add them as separate values...

If `textBox1.Text` is string type, why not just check if last char is `.` or `!` or `?`? — ochzhen, Nov 28 '20 at 03:53
Posted an answer, please check if it what you are looking for — ochzhen, Nov 28 '20 at 04:04

ochzhen · Answer 1 · 2020-11-28T04:13:52.073

1

If we need to only check the last character, we can do this using EndsWith method:

private void textBox1_TextChanged_1(object sender, EventArgs e)
{
    var text = textBox1.Text;
    if (text.EndsWith(".") || text.EndsWith("!") || text.EndsWith("?"))
    {            
         Task.Delay(200).Wait();
         MessageBox.Show("Thanks for your input!");
    }
    else
    {
         return;
    }
}

https://learn.microsoft.com/en-us/dotnet/api/system.string.endswith?view=netcore-3.1

edited Nov 28 '20 at 04:13

answered Nov 28 '20 at 04:01

ochzhen

156
2
5

Thanks, but I'm getting CS1503 error saying: Argument 1 cannot convert from char to string..... – Interestednewbie Nov 28 '20 at 04:12
I've corrected the answer to use string instead of char, please try it out ;) – ochzhen Nov 28 '20 at 04:14
Thank you very much! Seems to work smoothly now :-). Much appreciated. – Interestednewbie Nov 28 '20 at 04:25
Welcome! I'll appreciate if you accept this answer :) – ochzhen Nov 28 '20 at 04:27
Definitely the problem has been ccompletely solved. – Interestednewbie Nov 28 '20 at 04:52
`Task.Delay(200).Wait();` is an awful suggestion. Please don't recommend such things to new users of SO. – Alexei Levenkov Nov 28 '20 at 05:03

C# how to add more punctuation marks to the String.Contains Method?

1 Answers1