Concatenation function: splitting and merging cells

Assuming column A23 (#) is 22, B23 (Last name) is Daniell开发者_StackOverflow社区e, C22(middle name), D22 (last name) is Anderson.

This example has no middle name.

By using the =CON I want a combination of the first letter in the student’s first name, the first letter in their middle name and the first 6 letters of their last name. If the student does not have a middle name, the number in the A column and corresponding row should be used. If the student’s last name is shorter than 6 letters, their full last name should be used.

=left(B23,1) & if(C22<>"",left(C22,1),A23) & left(D22,6)