Calculated field in a dataset

Hi All,

I have a dataset with the following fields

Name Value

ABC 100

DEF 150

GHI 180

Now i need to have a calculated field DIFF which will calculate the difference in the value of the current row and the previous row. The report should have the following fields:

Name Value DIFF

ABC 100 NULL

DEF 150 50

GHI 180 30

Any pointers on how to achieve this requirement will help.

Thanks in advance,

Arun

You can do this with a custom function. Place the following, in the Code section of the Report. Using Report Designer this is on the Code tab of the Report Properties Dialog.

Private m_previousValue As Integer = 0

Public Function ComputeDifference(currentValue as Integer) as Integer

Dim diffValue as Integer = currentValue - m_previousValue
m_previousValue = currentValue

Return diffValue

End Function

The value for the calculated field:

=Code.ComputeDifference(Fields!Sales_Amount.Value)

|||

you can use previous function of the reproting services. these function will give the previous value.

substract the current value from the previous value.