如何检查单元格中的实际文本是否已经存在于Excel中的列中

Question

I'm editing an excel workbook who contains a lot of formulas and this workbook register products with a serial key, and product number... But I have some problems with it, because when the user are registering a product (with the serial code, and the product number) the product number always gonna be the same (I already have it, this is not the problem)..

The problem is when the user register the serial of the product, this serial can not be repeated in the workbook (column B), so I want that when the user introduce the serial, excel record all serials of the same column, and If in the column are another product with the same serial, excel gonna show a messageBox with the error, and the user gonna introduce another serial in the same row...

I don't know a lot of excel, but the program that I'm editing have messagebox if the user do some error..

Thank you, and sorry for my English.

Answer 1

Maybe this will help. Good luck! Using for and while loops in Excel

Edit: You can compare cells to each other. I suggest using two while-loops (each using a count variable) that continue until a cell is empty. The first variable (for example i) could be used to compare is to a second variable (for example j). Increment these when you have made the necessary comparisons.

Answer 2

Select column B and click data validation.

Use the below formula under custom,

=COUNTIF(B:B,B1)=1

This formula searches the number entered throughout the column B . It will error out if the value is present already on the same column. Let me know if you need anything else