Hi Krishna,
If you have multiple filters at the report level then try to check the condition whether user applied any filter the specifically on target block or not.
For example Source table is Block 1 and target table is block 2, then check whether there is any filter applied on the block 2 by using the report filter summary
var =Pos(ReportFilterSummary();"Block 2")
This will give 0 when there is no filter on Block2 else give some numeric value.
As Niraj mentioned you can use this formula output to hide the block 2
