How to negate a condition in PowerShell?

PowerShell uses various conditions for decision-making statements in the scripts. If a specified condition is “True”, then it will run the added command. Otherwise, the code block is executed. PowerShell also supports logical operators, such as “-and”, “-or”, “-xor”, “-not”, and “!”. These logical operators are utilized to connect multiple conditional statements. By utilizing them, you can test numerous conditions. More specifically, logical operators include negation operators like “-not” and “!”, used to negate the condition or, in other words, reverse the condition.

This post will discuss the negation operators and their usage.

How to Negate a Condition in PowerShell?

These are the methods/operators that can be used to negate a condition in PowerShell:

• “-Not” Operator
• “!” Operator

Method 1: Negate a Condition in PowerShell Using “-Not” Operator

The “-Not” operator is a negation operator. It is used to negate conditions in PowerShell that are added afterward.

Example

Now, let’s negate a condition using the “-not” operator. We will use the negation operator in the “if condition”, such as “if(-not(condition))”. The added condition will check if the value of the “$num” variable is greater than 9 and then negates the resultant value due to the “-not” operator:

Note that PowerShell is case-sensitive. So, both the “-Not” and “-not” will work the same.

Output

As we have negated the condition, that is why the “if statement” has been executed and the added message is displayed on the screen.

Method 2: Negate a Condition in PowerShell Using “!” Operator

Another negation operator that is used to negate a condition is a “!” operator. It works the same as the “-Not” operator.

Example

In this example, we will utilize the “!” operator for negating the condition “8 -gt 6”:

Output

The output shows that the condition has been negated successfully.

Conclusion

To negate a condition in PowerShell, two negation operators “-Not” and “!” can be used. You can add any of the mentioned operators in the “if” statement to negate a condition using the “if (-not(condition))” syntax, or “if (!(condition))”. This post has demonstrated several methods to negate a condition in PowerShell.