I have a filename in a string. I want to split the given string into 2 (1 is filename without extension, 2 is only extension) strings. Then add `_dev` to the end of first string and concatenate with 2nd one.

ex: 

```
Dim name as string="abc.txt"
Dim finalName as string

```

The `finalName` should be like this `"abc_dev.txt"`

Any suggestions please?