Sum of hours and minutes using expression rdlc

You can use the Split function to extract the hours and minutes, then convert them to total minutes.

For example, for the first value, and repeat this for each time value :

= CInt(Split(CStr(Fields!Ore.Value), ":").GetValue(0)) * 60 + CInt(Split(CStr(Fields!Ore.Value), ":").GetValue(1))

You can sum the total minutes using a custom code function in RDLC. Go to Report Properties > Code and add the following code to sum the minutes:

Dim totalMinutes As Integer = 0

Public Function AddMinutes(minutes As Integer) As Integer
    totalMinutes += minutes
    Return minutes
End Function

Public Function GetTotalTime() As String
    Dim hours As Integer = totalMinutes \ 60
    Dim minutes As Integer = totalMinutes Mod 60
    Return hours.ToString("00") & ":" & minutes.ToString("00")
End Function

In your report, use the AddMinutes function to add each time value:

=Code.AddMinutes(CInt(Split(CStr(Fields!Ore.Value), ":").GetValue(0)) * 60 + CInt(Split(CStr(Fields!Ore.Value), ":").GetValue(1)))

Finally, use the GetTotalTime function to display the total time in "HH:mm " format.

=Code.GetTotalTime()