I am trying to read a comma delimited text file to an array, then change just one element in the array and write it back to the text file. An example of what the text file would look like is:

data1,data2,data3
data1,data2,data3
data1,data2,data3

I want to change data in the last line at the last postion , data3, for example.

I am reading the file in with no problem. Im stuck on how to change the data and write it back to the text file.

Im a noob and any help would be a greatly appreciated! thanks!