Separate CSV into several by filtering through a column

I'm doing software to separate a CSV file into several CSV files, filtering by a column. I import the file and put it in a GridView and then I want to choose the filter column (in the example "PartRemark2"). Then put all items with the same value in a new CSV file. For example all lines that in the column "PartRemark2" have the value "MDF 16mm AN" in one file and all lines that have "MDF 16mm BL" in another. What would be the best way to do this? Think about making an Array with the contents of the "PartRemark2" column without repeating and then doing in IF and / or FOREACH to create the files. []