Question

I know if/else works, but I needed an alternative.

I am using

B = String.Concat(A.Substring(0, 40));

to capture the first 40 characters of a value.

If the value at A is more than 40, B is able to capture, but if the value of A is less than 40, there is no value being captured at B.

Answer 1

String.Concat does not serve your purpose here. You should rather do the following:

if(A.Length > 40)
    B = A.Substring(0, 40);
else
    B = A;