Validation based on user entered data - excel

Question

I'm attempting to create a form for data entry of lab results, which validates an answer based on the specification of the product tested. The user enters the following information: Product Code and SG result etc
My source data is a table with 4 columns,
Product Code, Description, SG low, SG high
SOURCE
When the user enters the Product Code and SG in the form I would like it to validate based on the specific range allowed for that product (from the source data), and have a dialogue box asking the user to reconsider the result entered (if it were outside of the range).
Easy enough to flag with conditional formatting in the results sheet, but I don't want my users to have access to it.
RESULTS
I need to refer to separate Range VLOOKUP to return the specs.
THE FORM
Thanks in advance!
(update)
Private Sub CommandButton1_Click()
Dim i As Integer
i = 2
While ThisWorkbook.Worksheets("Sheet2").Range("A" & i).Value <> ""
i = i + 1
Wend
Dim losg, loph, hisg, hiph As Double
losg = Application.WorksheetFunction.VLookup(ProdCode.Text, Sheet1.Range("A1:F24"), 3, False)
hisg = Application.WorksheetFunction.VLookup(ProdCode.Text, Sheet1.Range("A1:F24"), 4, False)
loph = Application.WorksheetFunction.VLookup(ProdCode.Text, Sheet1.Range("A1:F24"), 5, False)
hiph = Application.WorksheetFunction.VLookup(ProdCode.Text, Sheet1.Range("A1:F24"), 6, False)
If SGresult.Text < losg Then
MsgBox "SG result " & SGresult.Text & " too low"
ElseIf SGresult.Text > hisg Then
MsgBox "SG result " & SGresult.Text & " too high"
Else: MsgBox "SG result " & SGresult.Text & " just right"
End If
If pHresult.Text < loph Then
MsgBox "ph result " & pHresult.Text & " too low"
ElseIf pHresult.Text > hiph Then
MsgBox "ph result " & pHresult.Text & " too high"
Else: MsgBox "ph result " & phresult.Text & " just right"
End If
ThisWorkbook.Worksheets("Sheet2").Range("A" & i).Value = ProdCode.Value 'Enter Code in Column A
ThisWorkbook.Worksheets("Sheet2").Range("C" & i).Value = BNenter.Value 'Enter BN in Column C
ThisWorkbook.Worksheets("Sheet2").Range("D" & i).Value = DOMenter.Value 'Enter DOM in Column D
ThisWorkbook.Worksheets("Sheet2").Range("E" & i).Value = SGresult.Value 'Enter SG result in Column E
ThisWorkbook.Worksheets("Sheet2").Range("F" & i).Value = pHresult.Value 'Enter pH result in Column F
ThisWorkbook.Worksheets("Sheet2").Range("K" & i).Value = BatcherID.Value 'Enter Batcher ID in Column K
End Sub

Answer 1

Save Products in column "K" and valid result for respective product in column "L". Below code will give you desired output
Dim result, prod As String
Dim rng As Range
result = Val(resultText.Value)
prod = prodText.Value
ActiveSheet.Activate
On Error GoTo step:
Set rng = Range("K:K").Find(What:=prod, LookIn:=xlValues, LookAt:=xlWhole)
If rng.Offset(0, 1).Value <> result Then
MsgBox "The result entered is out of valid range!"
End If
Exit Sub
step:
MsgBox "Invalid Product"
Exit Sub

Answer 2

edited after OP clarified the "form" was a "UserFom"
You may want to check user input while he/she's editing/exiting any control instead of waiting for the CommandButton1_Click event and check them all together
Such a "modular" approach should keep code more easy to control and maintain
For example the TextBox Exit event could be used to check the user input as he/she's leaving it and have him/her come back to it in case of wrong input
Moreover
since "Product Code" must be chosen between those listed in "Source" worksheet column "A"
you may want to use a ComboBox control and have the user choose one out of a list
since "Product Name" must be the one corresponding to the chosen "Product Code"
you may want to use a Label control and have the user simply looks at what name corresponds to the product code he just chose
Following what above and assuming "ProductNameLbl" as the label name, your userform code could be something like follows:
Option Explicit
Private Sub UserForm_Initialize()
Me.ProdCodeCB.List = GetSourceData(1) '<--| fill Product Name combobox list with "Source" worksheet column 1 data
End Sub
Private Sub ProdCodeCB_Change() '<--| fires when the user change the combobox selection
Me.ProdNameLbl.Caption = Worksheets("Source").Cells(Me.ProdCodeCB.ListIndex + 2, 2) '<--| update Product Name label with the name corresponding to the chosen Product Code
End Sub
Private Sub SGresultTB_Exit(ByVal Cancel As MSForms.ReturnBoolean) '<--| fires upon exiting the SGresult textbox
Dim msgErr As String
With Me '<--| reference the Userform
If .ProdCodeCB.ListIndex <> -1 Then '<--| if a valid selection has been made in 'ProductCode' combobox
If Not IsValueInRange(.SGresultTB, GetProdCodeRange(.ProdCodeCB.ListIndex + 1), msgErr) Then '<-- if value out of range then...
With .SGresultTB
MsgBox "SG value " & .Value & msgErr _
& vbCrLf & vbCrLf & "Please reconsider the value you input in 'SG' texbox"
Cancel = True
.SetFocus '<--| get the user back to the textbox
' following two lines select the textbox text so that the user can delete it
.SelStart = 0
.SelLength = Len(.Text)
End With
End If
End If
End With
End Sub
'-------------------------------------------------
' helper functions
'---------------------------
Function GetSourceData(colIndex As Long)
' this function returns an array with "Source" worksheets data in passed column from its row 2 to last not empty one
With Worksheets("Source") '<--| reference "Source" worksheet
GetSourceData = Application.Transpose(.Range(.Cells(2, colIndex), .Cells(.Rows.Count, colIndex).End(xlUp)).Value)
End With
End Function
Function IsValueInRange(tb As MSForms.TextBox, rangeArr As Variant, msgErr As String) As Boolean
' this function returns a boolean (true/false) with the result of the checking whether the passed texbox (tb) text exceeds the passed range (rangeArr)
' msgErr is also set to some text if the range is exceeded
With tb
Select Case CDbl(.Value) '<-- prepare to act accordingly to its value
Case Is < rangeArr(1) '<--| if it's smaller than "SG Low" value
msgErr = " is lower than 'SG Low' = " & rangeArr(1) '<-- build the final part of the error message correspondingly
Case Is > rangeArr(2) '<--| while if it's greater than "SG High" value
msgErr = " is greater than 'SG High' = " & rangeArr(2) '<-- build the final part of the error message correspondingly
End Select
End With
IsValueInRange = msgErr = ""
End Function
Function GetProdCodeRange(iProd As Long)
' this function returns an array of the SG minimum and maximum values in "Source" worksheet corresponding to the chosen product
With Worksheets("Source") '<--| reference "Source" worksheet
With .Range("A2", .Cells(.Rows.Count, "A").End(xlUp)) '<--| reference its column "A" cels from row 2 down to last not empty one
GetProdCodeRange = Application.Transpose(Application.Transpose(.Cells(iProd, 1).Offset(, 2).Resize(, 2).Value)) '<--| return an array with "SG low" and "SG high" values corresponding to the product index passed
End With
End With
End Function
'-------------------------------------------------
as you may see, I named controls after the names you chose for them except for adding a suffix to tell what kind of control they are:
ProdCodeCB: "CB" -> it's a ComboBox control name
SGresultTB: "TB" -> it's a TextBox control name
ProdNameLbl: "Lbl" -> it's a Label control name