The value can be a constant or an expression, but it must either match the variable declaration type or be implicitly convertible to that type. For more information, see Expressions.
PowerShell includes the $PSItem variable and its alias, $_, as automatic variables in scriptblocks that process the current object, such as in the pipeline. This article uses $PSItem in the examples, but $PSItem can be replaced with $_ in every example.
The GetEnvironmentVariable function determines whether a specified variable is defined in the environment of the calling process, and, if so, what its value is.
User-defined variables can be set as read-only. There are naming restrictions for variables (example: you can't use secret at the start of a variable name). You can use a variable group to make variables available across multiple pipelines. Use templates to define variables in one file that are used in multiple pipelines.
This article explains how to create and use variable groups in Azure Pipelines. Variable groups store values and secrets that you can pass into a YAML pipeline or make available across multiple pipelines in a project. Secret variables in variable groups are protected resources.
I'm currently studying for az-104 azure exam and going through some scripting exercises. I can confirm the script below works, but I don't understand how... in the last few lines of the script the variable $vm is defined twice. how is this possible? …
To delete a variable, along with its value, use Remove-Variable or Remove-Item. This cmdlet does not delete the values of variables that are set as constants or owned by the system, even if you use the Force parameter.
Use custom variables To use custom variables in your tasks, enclose the variable name in parentheses and precede it with a $ character. For example, if you have a variable named adminUserName, you can insert its current value into a task as $(adminUserName).
