How to check the last character of a string in C#?

Question

I want to find the last character of a string and then put in an if stating that if the last character is equal to \"A\", \"B\" or \"C\" then to do a certain action

Answer 1

string is a zero based array of char.

char last_char = mystring[mystring.Length - 1];

Regarding the second part of the question, if the char is A, B, C

Using if statement

char last_char = mystring[mystring.Length - 1];
if (last_char == 'A' || last_char == 'B' || last_char == 'C')
{
    //perform action here
}

Using switch statement

switch (last_char)
{
case 'A':
case 'B':
case 'C':
    // perform action here
    break
}