BC30311: Value of type 'System.Data.DataView' cannot be converted to '1-dimensional array of System.Data.DataView'.

If it helps im looking to do a foreach loop where DATEPART(YEAR, Date) = " & e.Day.Date.Year & " AND " & "DATEPART(MONTH, Date) = " & e.Day.Date.Month,  in the datatable if there is an easyer why of doing this

if you declare the variable as array, you have to assign to a specific "slot" of the array:
dvholidays(1) = New DataView( ... )

or the like

i now get the following error :S The expression contains undefined function call DATEPART().
DATEPART(YEAR, Date) = " & e.Day.Date.Year & " AND " & "DATEPART(MONTH, Date) = " & e.Day.Date.Month,

that's a new error ... should normally be a new question

anyhow, DATEPART is not a ADO function, so you cannot use it directly

you need to prepare the data in the underlying rowset in a way you can filter as needed.
either you have 2 fields containing only the year and month values; or you have the date field as string in format yyyymmdd etc ... and you can do >= '201101' and < '201201' if you want full year 2011 ...

what about between dates?

what I wrote above, you need to make the data in a way you can work correctly.
with dataviews, this can be tricky, as you don't have "all" the functions you may need to make it efficient.
note that usually, if the underlying sql can solve the filtering directly, especially if the filter would return only very few rows from a huge data set, you are better of querying with the filter direclty in the sql ...

This question was asked (and probably answered) before I believe.

Execute a SQL to do the filtering from datasource (as probably already suggested).