Public/New-LoopAction.ps1
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function New-LoopAction { <# .SYNOPSIS Function to loop a specified scriptblock until certain conditions are met .DESCRIPTION This function is a wrapper for a ForLoop or a DoUntil loop. This allows you to specify if you want to exit based on a timeout, or a number of iterations. Additionally, you can specify an optional delay between loops, and the type of dealy (Minutes, Seconds). If needed, you can also perform an action based on whether the 'Exit Condition' was met or not. This is the IfTimeoutScript and IfSucceedScript. .PARAMETER LoopTimeout A time interval integer which the loop should timeout after. This is for a DoUntil loop. .PARAMETER LoopTimeoutType Provides the time increment type for the LoopTimeout, defaulting to Seconds. ('Seconds', 'Minutes', 'Hours', 'Days') .PARAMETER LoopDelay An optional delay that will occur between each loop. .PARAMETER LoopDelayType Provides the time increment type for the LoopDelay between loops, defaulting to Seconds. ('Milliseconds', 'Seconds', 'Minutes') .PARAMETER Iterations Implies that a ForLoop is wanted. This will provide the maximum number of Iterations for the loop. [i.e. "for ($i = 0; $i -lt $Iterations; $i++)..."] .PARAMETER ScriptBlock A script block that will run inside the loop. Recommend encapsulating inside { } or providing a [scriptblock] .PARAMETER ExitCondition A script block that will act as the exit condition for the do-until loop. Will be evaluated each loop. Recommend encapsulating inside { } or providing a [scriptblock] .PARAMETER IfTimeoutScript A script block that will act as the script to run if the timeout occurs. Recommend encapsulating inside { } or providing a [scriptblock] .PARAMETER IfSucceedScript A script block that will act as the script to run if the exit condition is met. Recommend encapsulating inside { } or providing a [scriptblock] .EXAMPLE C:\PS> $newLoopActionSplat = @{ LoopTimeoutType = 'Seconds' ScriptBlock = { 'Bacon' } ExitCondition = { 'Bacon' -Eq 'eggs' } IfTimeoutScript = { 'Breakfast'} LoopDelayType = 'Seconds' LoopDelay = 1 LoopTimeout = 10 } New-LoopAction @newLoopActionSplat Bacon Bacon Bacon Bacon Bacon Bacon Bacon Bacon Bacon Bacon Bacon Breakfast .EXAMPLE C:\PS> $newLoopActionSplat = @{ ScriptBlock = { if($Test -eq $null){$Test = 0};$TEST++ } ExitCondition = { $Test -eq 4 } IfTimeoutScript = { 'Breakfast' } IfSucceedScript = { 'Dinner'} Iterations = 5 LoopDelay = 1 } New-LoopAction @newLoopActionSplat Dinner C:\PS> $newLoopActionSplat = @{ ScriptBlock = { if($Test -eq $null){$Test = 0};$TEST++ } ExitCondition = { $Test -eq 6 } IfTimeoutScript = { 'Breakfast' } IfSucceedScript = { 'Dinner'} Iterations = 5 LoopDelay = 1 } New-LoopAction @newLoopActionSplat Breakfast .NOTES Play with the conditions a bit. I've tried to provide some examples that demonstrate how the loops, timeouts, and scripts work! #> param ( [parameter(Mandatory = $true, ParameterSetName = 'DoUntil')] [int32]$LoopTimeout, [parameter(Mandatory = $true, ParameterSetName = 'DoUntil')] [ValidateSet('Seconds', 'Minutes', 'Hours', 'Days')] [string]$LoopTimeoutType, [parameter(Mandatory = $true)] [int32]$LoopDelay, [parameter(Mandatory = $false, ParameterSetName = 'DoUntil')] [ValidateSet('Milliseconds', 'Seconds', 'Minutes')] [string]$LoopDelayType = 'Seconds', [parameter(Mandatory = $true, ParameterSetName = 'ForLoop')] [int32]$Iterations, [parameter(Mandatory = $true)] [scriptblock]$ScriptBlock, [parameter(Mandatory = $true, ParameterSetName = 'DoUntil')] [parameter(Mandatory = $false, ParameterSetName = 'ForLoop')] [scriptblock]$ExitCondition, [parameter(Mandatory = $false)] [scriptblock]$IfTimeoutScript, [parameter(Mandatory = $false)] [scriptblock]$IfSucceedScript ) begin { switch ($PSCmdlet.ParameterSetName) { 'DoUntil' { $paramNewTimeSpan = @{ $LoopTimeoutType = $LoopTimeout } $TimeSpan = New-TimeSpan @paramNewTimeSpan $StopWatch = [System.Diagnostics.Stopwatch]::StartNew() $FirstRunDone = $false } } } process { switch ($PSCmdlet.ParameterSetName) { 'DoUntil' { do { switch ($FirstRunDone) { $false { $FirstRunDone = $true } Default { $paramStartSleep = @{ $LoopDelayType = $LoopDelay } Start-Sleep @paramStartSleep } } $ScriptBlock.Invoke() } until ($ExitCondition.Invoke() -or $StopWatch.Elapsed -ge $TimeSpan) } 'ForLoop' { for ($i = 0; $i -lt $Iterations; $i++) { switch ($FirstRunDone) { $false { $FirstRunDone = $true } Default { $paramStartSleep = @{ $LoopDelayType = $LoopDelay } Start-Sleep @paramStartSleep } } $ScriptBlock.Invoke() if ($PSBoundParameters.ContainsKey('ExitCondition')) { if ($ExitCondition.Invoke()) { break } } } } } } end { switch ($PSCmdlet.ParameterSetName) { 'DoUntil' { if ((-not $ExitCondition.Invoke()) -and $StopWatch.Elapsed -ge $TimeSpan -and $PSBoundParameters.ContainsKey('IfTimeoutScript')) { $IfTimeoutScript.Invoke() } if ($ExitCondition.Invoke() -and $PSBoundParameters.ContainsKey('IfSucceedScript')) { $IfSucceedScript.Invoke() } $StopWatch.Reset() } 'ForLoop' { if ($PSBoundParameters.ContainsKey('ExitCondition')) { if ((-not $ExitCondition.Invoke()) -and $i -ge $Iterations -and $PSBoundParameters.ContainsKey('IfTimeoutScript')) { $IfTimeoutScript.Invoke() } elseif ($ExitCondition.Invoke() -and $PSBoundParameters.ContainsKey('IfSucceedScript')) { $IfSucceedScript.Invoke() } } else { if ($i -ge $Iterations -and $PSBoundParameters.ContainsKey('IfTimeoutScript')) { $IfTimeoutScript.Invoke() } elseif ($i -lt $Iterations -and $PSBoundParameters.ContainsKey('IfSucceedScript')) { $IfSucceedScript.Invoke() } } } } } } |