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Now, let's look at ways of manipulating and working with strings.

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Let's define a string, PowerShell, save as a $s.

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Let's pipe $s to Get‑Member.

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There are lots of methods here that you can see,

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and we're going to go through some of them,

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and one Property, Length, which shows me how long the string is.

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So if I look at that, I can see that PowerShell is 10 characters long.

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We looked at this in the lesson on arrays,

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but remember,

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strings can be treated as an array, so the first index of the string 0 is P,

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or if I want to, I can use the range operator and say,

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hey, get me elements 3 through 6, and there we go,

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and that's treated then as another array.

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You can take strings and make them say all lowercase,

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or you can make them all uppercase.

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When you invoke these methods,

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this does not change the original or underlying object,

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so $s hasn't changed.

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All I did was invoke a method, and PowerShell wrote a new result to the pipeline.

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Now, let's parse $s,

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and there's a substring method that can be used a number of ways.

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Let's take $s and get substrings starting at index 5.

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Because I did not specify a length,

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PowerShell just went and gave me the rest of the string starting at index 5.

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Although if I wanted to, I could start at,

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in this case, 0 and give me 5 characters.

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It's really not that difficult to try to parse strings out.

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Remember though, PowerShell is all about objects,

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and I don't want you to be focusing on, oh,

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how do I, I need to parse strings and parsing output.

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This is the kind of thing that you might do if you have to parse a

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log file, for example, or you need to tweak some output in some

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custom objects that you are creating.

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Don't try to look at a Powershell command,

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and look at the output, and try thinking,

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okay, how do I parse this as string output?

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Don't go down that route.

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So going back to this example,

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$s.Substring(5) is just writing another object to the pipeline,

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so I can say, hey, make that all uppercase.

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Let me show you something else with strings,

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and this is something that you will encounter.

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So I'm going to create $t, and I'm going to create the string Pluralsight,

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but I'm putting spaces around it.

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Because when you're working with data in PowerShell you

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may not always know where it comes from,

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and you may need to clean it up, and that's what we're going to do here.

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You can see the space before, and you really can't tell

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that there is whitespace after the string.

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I can look at the length property and see that it is 15.

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That includes the whitespace.

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PowerShell has a number of methods that you can use on strings.

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You may, for example, only want to trim the end,

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meaning, get rid of all the whitespace that is at the end of the string,

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and it's kind of hard to see in this example, TrimStart

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a little bit easier to see there, or you can use the Trim method,

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which will trim the entire object, both start and end.

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We'll save that to $r.

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Now that looks right.

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And if I look at the length property, I can see that it is 11,

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so that previous length, obviously, were all whitespace characters.

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And here's how you might use all of this.

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So I'm going to create a variable to a txt file,

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so my work folder,

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and you have this file as part of the course downloads

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so if you wanted to play with here.

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So I do Get‑Content and see what's in that file.

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So this is supposed to be a list of computer names.

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I just have a localhost several times,

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Offline for a computer that's not available,

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and again, localhost.

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And you can see,

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I've got some blank lines and some extra spaces around localhost,

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so I need to kind of clean up this file if I want to use it.

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If I were to try to do this, for example,

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Get‑Content $f and run Test‑Connection, Test‑Connection will then take

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the contents of $f and use it for the computername.

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The first one works because localhost has no spacing,

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then I get some blank lines, I'll get an error for Offline,

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and if you look at the messages there, you'll see Testing connection to,

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and then in quotes, it's got localhost,

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and you can actually see that there are spaces around that.

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Well, actually, I don't want that.

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So I want to be able to clean this up, and here's how we can do that.

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So we'll do Get‑Content.

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Now,

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for each string that comes through from

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Get‑Content, now this is one way to do it,

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and I'm going to use, you know,

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some new PowerShell 7 syntax we looked at earlier in the course.

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If the length is greater than 0, then I'm going to run Test‑Connection,

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and for the computername, use the current object,

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but Trim all of the whitespace, both front and back,

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on that; otherwise, that's the single colon there,

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otherwise, I'm going to Write‑Warning "Skipping blank".

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So there we go.

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I can see that I get my results for localhosts,

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I get skipping the blank lines,

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and I get the error message for the computer that is Offline,

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which is perfectly fine.

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From a more practical perspective, this might be a better approach though.

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Let's do Get‑Content again, get $f, where the length is greater than 0.

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And then for each result,

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I want to take the $_ against the current object in the pipeline,

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so that string that comes through that has a length greater than 0,

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trim it and use that as a computername for Test‑Connection.

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Now, I don't worry about the blanks because those really don't matter to me.

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I get the computers that work, localhosts,

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and I get my error message for Offline.

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That's probably an easier, cleaner way to do this.

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Now,

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the reason that I did not do Get‑Content pipe to Where object pipe to

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Test‑Connection is because I needed to invoke that Trim method on

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every object that came through the pipeline.

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So I needed to use for each object in order to achieve that.

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All right, next,

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I want to show you about other things that we can do with strings.

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So remember, we've got $s here, so it's PowerShell.

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Strings also have a replace method.

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Different ways that we can use it.

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So I can say replace all the es with the number 3.

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Again, this doesn't change $s.

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It just writes a new string to the pipeline.

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There is a replace method that we can use.

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And one thing to notice about this method, it is case sensitive.

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So if I try to replace the lowercase p with X, it doesn't work.

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So I would have to do something like this,

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ignore the casing of the string, and just replace any P,

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capital case or lowercase with X.

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Remember,

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you will often be working with data and values from commands that you

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have no way of knowing what is in that variable,

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and so you may need to take certain things into account,

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and this is one example.

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So let me do this.

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All right, see if you can follow this.

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Remember we talked about the importance of leveraging the object notation.

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So I'm going to take $s, and I'm going to replace o with the set of parentheses.

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Remember, that's writing a new object of the pipeline.

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I'm then going to replace that object,

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replace the e with the greater than sign and then replace h with the &.

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In other words, I'm going to make three replacements all at once,

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and there we go.

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Now,

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another option though for replacing if we don't want to worry too much

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about case sensitivity is use the replace operator.

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So now, I can take $s and say replace P with the!, and that will work.

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So the replace method is case sensitive unless you use that ordinal ignore case,

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or you can use to replace method, which is not case sensitive.

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The other reason that you might want to use to replace method

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is that you can use regular expressions.

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So I'm going to replace, in the string jeff789,

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I'm going to replace any number with the letter X,

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and there we go.

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So with that in mind,

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let's look at some ways that we can take advantage

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of these operators and methods, and we create a string,

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$data, and this might be data that you get from a log file.

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Now, I can split that string using the split method into an array.

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And because that is an array of object, and we saw this in the array module,

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I can invoke a method,

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and PowerShell will invoke this method on all members of the array.

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So I can take the data, split it on the pipe,

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or the vertical bar, that's going to leave some spaces,

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but no problem because I'm going to trim it.

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So if I look at my array, you can see, well,

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it may be kind of hard to see, but you see,

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I got rid of, for example, the leading space in front of deco,

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so that's very useful.

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See if you can follow what I'm doing here though.

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Remember, $arr is an array, element 0 is the first element in the array,

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art, art is a string, strings can be arrays,

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so element 0 in art is letter a, right,

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so let's see if you can follow along here.

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I'm going to initialize an empty array, $name,

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and I'm going to add to $name this command.

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Let me type it out here, and let me explain then what we're doing.

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All right, So I'm going to take the first element in the array $arr,

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which is art, right, and I'm going to use the replace method.

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Now,

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I'm going to replace the first element in the array

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and the first letter in the array, right,

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a, the lowercase a,

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and I'm going to replace that with basically the same character $arr[0][0].

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Now, that is going to actually technically be a character object,

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and so in order to use the ToUpper method,

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I need to turn it to a string.

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So I'm taking the first character in art,

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turning it back into a string, and then invoking the ToUpper method.

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This seems more complicated than it is,

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but that's only because I'm trying to explain to you what is happening.

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Eventually, this all becomes second nature, and you won't even think about it.

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And then I'll do the same thing with the last name.

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So the second element in the array $arr is deco.

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And, again, I'm going to replace the first letter,

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which is lowercase, with the first letter toString and make it uppercase.

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So now, $name will have the first name and last name, all in proper case.

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There are other ways that you could do this,

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but I wanted to use this example to demonstrate these methods and how

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you can use PowerShell to string things together. Once I have this, and

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maybe this is part of a script or something that I'm building to

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provision a user account, I could then display a message to the user,

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writing Creating user, and I'm going to take that name array and join

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it with spaces.

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So now, I can say, hey,

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I'm creating user art deco and feed that back to the

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user so they know what is going on.

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There are no cmdlets to do any of this.

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There are methods and operators,

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and I'm just using the PowerShell language to give me information that I need in order to do my job.