how to compare cellvalue with value in database?

Question

i want to create a table which will trigger an alert based on the condition.
the alert will change the box color into red color.
the condition is based on the 'alert_type1' in 'parameterDataTable' table.
the user can change the condition (i name it as a) in the parameterDataTable and it will link to the alert function.
i try to do like this:
if cellvalue < a then
'the code for the cell to change color
end if
which the a is the value that the user key in and the a value is from the parameterDataTable(alert_type1)
but the problem is it cannot be read. i don't know how to link the a variables with the parameterDataTable. here, i attached my code on what i've got so far and it's still not working. i'm still new in using vb.net and i hope that you all can help me..
many thanks in advance. :)