C# WPF Partially search DataGridView -

i have window in bind datagrid source datatable tree-like structure. in window, have textbox, , 2 buttons ("contains", , "exact"). , following sample data (in text), along table image:

comedy   english     21 jump street       c tatum       j hill     22 jump street       c tatum       j hill     dumb , dumber       j carrey       j daniels action   english     mission impossible 5       t cruise       j renner   hindi     singham       devgn       k agarwal 

http://oi58.tinypic.com/301mtko.jpg

i have few things do:

using text entered , depending on button clicked, i'd filter last column (lead actor) of gridview (just update grid view, not saving datatable). example, typing "tum" , clicking 'exact' similar search done datatable using dataview, in case, returning nothing. when 'contains' button clicked, should return (gridview table):

comedy   english     21 jump street       c tatum     22 jump street       c tatum 

and 'contains' search "ar" should return (on gridview table):

action   hindi     singham       k agarwal 

i have read here , there should use bindingsource (https://stackoverflow.com/a/21845837/5003918), not sure how use (and return hierarchy instead of matching rows). actual data probably have unique last columns (unless contains search used).

lastly, have "export" button use export current gridview csv.

• to summarize need with:
  1. "contains" search gridview
  2. "exact" search gridview (bindingsource?)
  3. export gridview data (exporting datagridview csv file ; getting error atm)

i hope, have (accurately) provided enough information obtain help. :)