Basic Calculation of Start - End Time

Hi guys,

I hope you can help with an equation.

i would like to work out the total number of hours worked. It is a basic calculation of End Time - Start Time = Hours Worked.

My start and end times are saved to my spread sheet in the following code, and I would like to use the 3rd line of the code to do the calculation and save the data to that specific cell:

ws.Cells(rowToEdit, 126).Value = Me.txtWorkShiftStart.Value
ws.Cells(rowToEdit, 127).Value = Me.txtWorkShiftEnd.Value
ws.Cells(rowToEdit, 129).Value = Me.txtWorkShiftEnd.Value - Me.txtWorkShiftStart.Value

Example:

WorkShiftStart = 08:00
WorkShiftEnd = 15:00

The equation: 15:00 - 08:00 = 7:00

Any help would be much appreciated!