Excel VBA 自动查找数字的上限和下限

Question

I am trying to find the upper and lower bound of a number by using Excel VBA but I have no idea how to write the code for that. So for example, I am given the number 35 (Cell E6). And in the list of values (in column A) that I am given, I want the program to automatically find 30 and 40 respectively and store the values beside 30 and 40 in 2 variables for some further calculations. Is that possible? Thanks a lot in advance:)

Answer 1

If you have Office 365, that would be a good occasion to use the brand new Excel XLOOKUP function which is also available in VBA.

For example:

Dim wb As Workbook
Set wb = Workbooks("MyWorkbook.xlsm")

Dim ws As Worksheet
Set ws = wb.Worksheets("Sheet1")

Dim LowerBound As Long
Dim UpperBound As Long

With ws
    LowerBound = WorksheetFunction.XLookup(.Range("E6"), .Range("$A$1:$A$1000"), .Range("$A$1:$A$1000"), CVErr(xlErrValue), -1, 1)
    UpperBound = WorksheetFunction.XLookup(.Range("E6"), .Range("$A$1:$A$1000"), .Range("$A$1:$A$1000"), CVErr(xlErrValue), 1, 1)
End With

Debug.Print LowerBound
Debug.Print UpperBound

More details on how to use XLOOKUP

The key here is to use the 5th argument of the function (match mode) to your advantage. To get the "lower bound" we ask for the exact match or next smaller and for the "upper bound" we ask for the exact match or next larger.

Caveats and notes:

• In the code above, the lookup_array and the return_array ranges are hardcoded, but it would be better to simply define a range object and refer to it instead.

• If the lookup_value is greater than the biggest number in the lookup_array , it will give you a run-time error or the returned value will be 0.

• Make sure you have the Immediate Window visible (Ctrl+G) if you want to see the results of the Debug.Print statements.