conditions.There's another syntax that doesn't overwrite an existing This lets PowerShell know that this is all one parameter. It soon became apparent that this was less than optimal when I needed to move a script from Dev\UAT into production because certain variables would need to be updated between the environments.Fortunately, like most languages, PowerShell permits the use of parameters, but, like many things in PowerShell, there’s more than one way of doing it. Type in the same command as above but add a dash (-) at the end.PowerShell should now pop up a little dropdown that shows you the available parameters. (An interesting side note: if you do put a space after comma, it will still treat the list of drive letters as a single parameter, the comma basically eats the space. "If this script were really going to do something, it would do it on $servername in the $envname environment""If this script were really going to do something, it would do it on $servername in the $envname environment""Adding $anint to itself results in: $($anInt + $anInt)""But trying to add $maybeanInt to itself results in: $($maybeanInt + $maybeanInt)""If this script were really going to do something, it would do it on $servername in the $envname environment""If this script were really going to do something, it would do it on $servername in the $envname environment""If this script were really going to do something, it would do it on $servername in the $envname environment""$($args[$i]) has  $($diskdata.Used) Used and $($diskdata.Free) free""$($drive1) has  $($diskdata.Used) Used and $($diskdata.Free) free""$($drive2) has  $($diskdata.Used) Used and $($diskdata.Free) free""$($drive3) has  $($diskdata.Used) Used and $($diskdata.Free) free"# don't bother testing for drive3 since we didn't even have drive 3 "$($drive) has  $($diskdata.Used) Used and $($diskdata.Free) free"

The Invoke-Command:ScriptBlock key set to a default value of the System event log because the script block is enclosed in a second set of braces. He is the author of: IT Disaster Response: Lessons Learned in the Field.

This ability, combined with the ability to read JSON files in a previous article should give you a great deal of power to be able to control what your scripts do and how they operate. Use If a parameter can accept multiple values, an array, you can set multiple He started working with SQL Server 4.21a in 1995 and has survived numerous upgrades. You can do this by testing to see if the parameter is null and then prompting the user for input.You will notice that this combines both, a default parameter and testing the see if the You can run this from the command line in multiple ways:It will do exactly what you think: use the passed in servername value of And in this case, it will override the default parameter for the environment with There is another way of ensuring your users enter a parameter when it’s mandatory.You’ll notice it forces you to enter the servername because you made that mandatory, but it still used the default environment name of You can still enter the parameter on the command line too:And PowerShell won’t prompt for the servername since it’s already there.Generally, I find using named parameters far superior over merely reading the arguments from the command line.

result as the default parameter value.If a parameter accepts a script block value, enclose the script block in an Delay binding does not work for parameters defined as type ScriptBlock or System.Object.The script block is passed through without being invoked. To change A typed parameter that accepts pipeline input (by Value) or (by PropertyName) enables use of delay-bind script blocks on the parameter.The delay-bind script block is run automatically during ParameterBinding.The result is bound to the parameter. Save the following script as What if you don’t control the data being passed, and the passing program passes items in quoted strings?To simulate that run the script with a slight modification:However, keep in mind if someone tries to call the same script with an actual string such as:It will return a gross error message, so this can be a double-edged sword.When running a script, I prefer to make it require as little typing as possible and to eliminate errors where I can. Cmdlet Parameters. This is a case where you will need to run the saved file from the ISE Console and supply a value for the argument. The name of the parameter is always preceded by a hyphen (-) The Parameter_value often needs to be provided in a specific data type (e.g. values as the default values.