Introduction:

In Power Automate, for doing validations Not Function will be used. As an example, an String variable used to work with Not function.

Step 1:

Login to the required Power Apps environment using URL make.powerapps.com by providing username and password and click on Flows on the left-hand side as shown in the below figure.

Step 2:

After Step 1, Click on New Flow and select instant cloud flow and provide the trigger as Manually trigger a flow and click on Create as shown in the below figure.

Step 3:

After Step 2, name flow as Not Function and take initialize variable and name it as Set Name of the Person Variable to CommonManVenkat with the following fields

Name :  Name

Type :  String

Value : CommonManVenkat

as shown in the below figure.

Step 4:

After Step 3, take compose action and name it as Check if Name Variable CommonManVenkat have Venkat and provide

Inputs: contains(variables(‘Name’),’Venkat’)

and click on ok/ update as shown in the below figure.

Step 5:

After Step 4, take compose variable and name it Set the Usage of Not Function in Name Variable and provide

Inputs :     not(expression: boolean)

As

not(contains(variables(‘Name’),’Venkat’))

And click on ok/update as shown in the below figure.

Step 6:

After Step 5, run and test the flow and observe true and false values were returned shown in the below figure

Note:

1. Make sure to save and run the flow whenever you try expressions.
2. MS documentation is found at here

Conclusion: In this way we can use not function so that basic validation on strings in power automate can be done easily.