Functions with a Single Argument
In a script (called WrapMath.ps1) I declare the class
$class = 'System.Math'
and the list of methods…
$methods = 'abs','acos','atan','atan2','ceiling','cos','cosh','equals','exp',` 'floor','log','log10','sign','sin','sinh','sqrt','tan','tanh','trunc'
In this case, all of the above methods are ones that except one argument. I then define a function prototype with place holders for the method and class
$Prototype = @' <# .Synopsis |method| from static class |class| .Description |method| from static class |class| .Example |method| -2.56 .Link [|class|]::|method| #> function global:|method| { $args[0] | foreach{return [|class|]::|method|($_)} } '@You’ll notice the document string preceding the function declaration. This actually works. The next part is the slick bit… loop over the methods, replacing |method| and |class| each time in the prototype and use Invoke-Expression to dynamically create the command.
$methods | foreach{ Invoke-Expression (($Prototype.Replace('|method|',$_)).Replace("|class|",$class)) }You’ll notice I make use of a pipeline in the function prototype, so that these methods all work with an array or a single value. So they are actually a bit more useful than just calling [system.math]::method
Functions with 2 Arguments
For functions that except two arguments you can do the following:
################################################################################ #Methods that take two arguments. The first argument can be an array. The #second must be a single value. So you could use the pow method to square #each element in an array. ################################################################################ $class = 'System.Math' $methods = 'pow','round','IEEERemainder' $Prototype = @' <# .Synopsis |method| from static class |class| .Description |method| from static class |class| .Example |method| 5.2 3 .Link [|class|]::|method| #> function global:|method| { $parm2 = $args[1] $args[0] | foreach{return [|class|]::|method|($_,$parm2)} } '@ $methods | foreach{ Invoke-Expression (($Prototype.Replace('|method|',$_)).Replace('|class|',$class)) }Max and Min
Finally Max and Min are special cases, as they are some-what recursive
################################################################################ #Max and Min methods. These work for any size array of values. ################################################################################ $class = 'System.Math' $methods = 'max','min' $Prototype = @' <# .Synopsis |method| from static class |class| .Description |method| from static class |class| .Example |method| 10,12,13,14 .Link [|class|]::|method| #> function global:|method| { $retval = $args[0][0] $args[0] | foreach{$retval = [|class|]::|method|($_,$retval)} return $retval } '@ $methods | foreach{ Invoke-Expression (($Prototype.Replace('|method|',$_)).Replace('|class|',$class)) }I’ve done a similar thing with the System.IO.Path class that I will write about later. Hope this helps someone out.
