Issue with Dlookup statment [closed]

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Closed 4 days ago.

Private Sub WeightFrom_BeforeUpdate(Cancel As Integer)
    DLookup("Regimen", "AdminTableRegimenPerWeight"," & [FrmAdminRegimen].Form![WeightFrom] &" Between [WeightTo] And [WeightFrom]") Then

        MsgBox "Weight already assigned!"
        Me.WeightTo = Null
    End If

End Sub

Error is showing with the above Dlook code.

I have a table in which I assign particular dosage based on patient's weight. So if a patient weight lies between 33 to 50 then I prescibe certain amount of dosage value for that Medicine. So there are total of around 15 Medicines. What I want to do is when assigning medicine I want the system to check if the weight values for that medicine does not lie between any previous weights for that particular medicine. Something like BeforeUpdate : Dlookup Medicine Weight inbetween Suppose :

Regimen_________ WeightFrom__________WeightTo__________Dosage_______Unit
A_____________________33_______________55______________450__________mg

B_____________________56_______________77______________500__________mg

来源：https://stackoverflow.com/questions/59610295/issue-with-dlookup-statment