Include IPA symbols in C# programming

Question

How to include International Phonetic Alphabet(IPA) symbols in C# programming.

Part of the program I tried so far given below

 

for (int i = 0; i < str.Length; i++ )

{

char s = str.ToCharArray()[i];

if (s == 'y')

{

ss[i] = '?';

}

else if (s == 'a¯')

{

ss[i] = 'a';

}

else

{

ss[i] = str.ToCharArray()[i];

}

}

 

Here an error is displayed for the code red marked as 'Too many characters literal'.

Please suggest me what to do? Should I declare IPA symbols before writing the above code?If so how?