---
title: "Example 4 - Adding/Editing Work Order (Line) Item - Ensure Unique Input Value"
canonical: "https://help.fieldbuddy.com/space/FBDOCS/5985173525/Example%204%20-%20Adding%2FEditing%20Work%20Order%20(Line)%20Item%20-%20Ensure%20Unique%20Input%20Value"
format: markdown
---
For Details check: [https://upperdeck.atlassian.net/wiki/spaces/FBDOCS/pages/5381455880](https://upperdeck.atlassian.net/wiki/spaces/FBDOCS/pages/5381455880) 

This example might not have an immediate practical use, but it can serve as a starting point for creating one.

This example relates to: [https://upperdeck.atlassian.net/wiki/spaces/FBDOCS/pages/5984616474](https://upperdeck.atlassian.net/wiki/spaces/FBDOCS/pages/5984616474)

It prevents adding a code that has already been added before.


```
EXAMPLE-4 Not unique code at Edit Work Order Other Expenses
f=()=>{return 22 >= 0; };Boolean(f());
Pass: false
ErrorMessage: The barcode that you're trying to use was already used before
```