Change dimension value with global variable name in VBA

Hi everyone,

I have dimension in sketch as D1@Sketch1 and this dimension value is 50. I want to change D1@Sketch1's Value as NewDiameter. NewDiameter is global variable name and NewDiameter 's value is 40. My code isnt working.

Sub main()

Dim swApp As Object

Set swApp = Application.SldWorks

Set swModel = swApp.ActiveDoc

Dim mydimension As Object

Set mydimension = swModel.Parameter("D1@Sketch1")

mydimension.SystemValue = "=""NewDiameter"""

End Sub

SolidworksApi/macros