Tag Archives: Function

Baby, It’s Cold Outside

I don’t know about your neck of the woods, but it is downright Arctic here. So I thought I’d polish up my PowerShell function to get weather data.

This function uses the Yahoo weather RSS feed for US locations. The function uses the Invoke-RestMethod to get an entry for a given zip code. I set my zip code as the default and suggest you do the same. You will need to modify the default value in the code above. Invoke-RestMethod gives me an XML document so it isn’t too difficult to pull out the values I want and construct a custom object. I even use some regular expression named captures to break out the location and time. So hopefully there are some good learning examples here.

Anyway, quite frigid here, and this is already 5 degrees warmer than when I got up.

weather

Hope you are staying warm.

Using Optimized Text Files in PowerShell

documentIf you are like many IT Pros that I know, you often rely on text files in your PowerShell work. How many times have you used a text file of computernames with Get-Content and then piped to other PowerShell commands only to have errors. Text files are convenient, but often messy. Your text file might have blank lines. Your list of computernames might have a extra spaces after each name. These types of issues will break your PowerShell pipeline.

You can use Where-Object and filter out these types of problems. Or you can use a new function I wrote called Optimize-Text.

I’ve tried to add features to this command for what I think are common issues with text files. The core features are to remove any blank lines and trim leading and trailing spaces from each line of text. I’m working under the assumption that you will be using a command like Get-Content with some sort of list that you want to use with another cmdlet. You can insert Optimize-Text, in between.

For example, perhaps you want a quick and dirty ping test for a list of computers:

In this example, computers.txt is pretty mangled. There are blank lines and some names have leading and/or trailing spaces. Using Optimize-Text, fixes those issues. But wait…there’s more!

The advantage to using PowerShell is that everything is an object. Often, it helps to take advantage of pipeline binding. For example, the Computername parameter for Test-Connection accepts pipeline input by property name. So if the incoming object has a property that matches the parameter name, it will use it. Optimize-Text allows you to specify a property name. When you do, each line is turned into a custom object with a single property name.

This means I can run a command like:

And if you download this function today, I’ll throw in parameters to convert each line of text to upper case, to ignore lines with a specified comment character and to do additional filtering with a regular expression pattern!

By the way here’s what the text file looks like:

While it would be nice to think that all of the text files you use in PowerShell and neat and tidy, there’s no guarantee someone else might not come along and mess it up again. Hopefully, this function will help.

Please let me know how this works for you in the real world, or what other common problems you run into with text files. Be sure to look at full help and examples. Enjoy!

Look at Me!

bluelight Last week I posted some ideas on how to add notifications to your scripts. Those ideas were variations on the old school “Press any key to continue” prompt that I assume many of you are familiar with. Most of those concepts should work for you, but they assume you looking at the PowerShell window. I thought about those situations where perhaps I only see a portion of the PowerShell window. Wouldn’t it be helpful if you had some other visual clue, like a flashing light? I thought so and whipped up Invoke-Flasher. I’ll admit the name might have an unexpected connotation, but you can always change it.

Here’s the function, and then I’ll explain how to use it.

This function will only work in the PowerShell console, not the PowerShell ISE because it uses the ReadKey() method from $host.ui.rawui to detect if the user hits any key. The main portion of the function keeps looping through until a key is pressed. Each time through the background color of the host UI is toggled between the current color and Red, or whatever console color you specify. Each time through the script writes your text and “Press any key to continue”. I use the Coordinates property of the host to write to the same spot on the screen each time so there’s no scrolling.

By default, the Write-Host line will “flash” by alternating the background color. Or you can use the -FullScreen parameter which will clear the host everytime. If you use this option in your script, make sure the main part of your script is saving data somewhere because you won’t see it. Here’s an example of how you might use it.

After the main portion of the script completes, the flashing message is displayed after the results. If you want to use the fullscreen approach, you could try something like this:

When the main portion of the script finishes you’ll get a flashing screen with the text message. Press any key and you’ll get the results.

I have to say I’m intrigued by this function and can already think of some ways to improve it. If you have suggestions or find this useful, I hope you’ll let me know.