Using the Watch Window

Quick reference

• 00:05 >> The next window that I want to look at is the watch window which,
• 00:08 you can see down in the bottom right-hand corner here.
• 00:12 And we can get this the same way that we get the others by just going up to
• 00:15 the view tab and grabbing it from the watch window and
• 00:17 that will bring it up into this space.
• 00:19 Now. The interesting part about this this lets
• 00:22 us watch certain expressions to see what happens and
• 00:24 take action on them depending on what we've actually chose to do.
• 00:27 In this case I have a slightly modified version that I had before, that's
• 00:32 simulating that what happens when we get a really long routine and something changed
• 00:36 over time we're trying to keep bugging you know sure exactly what happened.
• 00:39 We sort of expect that one thing is being fed in, but
• 00:41 then we're getting something a little bit different later on.
• 00:43 So what you can see here, if we actually take a look at this particular routine,
• 00:47 is that if I go and actually pick up three cells here, what it's going to do is it's
• 00:51 going to go through and it says i'm going to set the range to selection and
• 00:55 it's going to feed feed me back the address of A3 to A5.
• 00:58 But then you'll notice that this range has been reset and resized.
• 01:01 So instead of actually having a one-by-three block,
• 01:04 we're gonna get a two-by-two block.
• 01:06 It's resizing that range, the new address is A3 to B4.
• 01:10 So it's actually this block right here, which is being copied and pasted.
• 01:16 Next to what we had, now this is interesting.
• 01:20 The key part that I sort of want to look at in this particular case, is I'd like to
• 01:23 go back and say well, what if we're expecting it to only be one column.
• 01:28 So what I am going to do right now is say.
• 01:30 How could I actually figure out, if I go through this how to check that?
• 01:35 So we can set our range of selection and now that we've got a range object I can
• 01:39 actually drill into the object to figure what I can get access to.
• 01:42 So I'll say questionrng.
• 01:44 Dot.
• 01:44 Let's see- if I type in C, I get to cells.
• 01:49 I wonder, do you think it will allow me to actually take a look at columns.
• 01:53 Hey, there we go, columns.
• 01:55 So, we'll go to arrange columns.
• 01:56 Account, and it tells me its 1.
• 02:00 So this is kinda neat, what I'm gonna do now,
• 02:02 is I'm gonna go right click and I'm gonna add a watch.
• 02:05 And that watch is gonna be for rage.columns.count.
• 02:10 And I'll just say watch the expression for right now,
• 02:13 and you'll see that it has a value of 1.
• 02:16 So if I go back and I stop it and try this again, it has no value.
• 02:22 This will say object value variable not set,
• 02:24 because there's nothing been set to it yet.
• 02:26 As we step in, there we are, we assigned the selection.
• 02:30 It's now got one value or a value of one column.
• 02:33 When I go in, the next line that I'm gonna execute, still got a value of one,
• 02:36 but the next line that I'm gonna execute, now says there's a value of 2,
• 02:41 at which point it will do its copy and it will do its paste.
• 02:43 Okay, so this is kind of interesting.
• 02:45 Now, at this point what I'm going to do, is I'm going to go back, and
• 02:50 I'm going to try this again.
• 02:51 And I'm going to say, you know what instead of watching this,
• 02:53 what I'd like to do is I'd like to change this.
• 02:57 And say break when the value changes.
• 03:00 Because now what I can do, is I can come back over here, and I can run the routine.
• 03:04 Watch what happens when I just click Run.
• 03:05 Zoom hit runs until the first time the value changes,
• 03:09 it changed from nothing to 1.
• 03:11 When I run again.
• 03:14 It stops again because it changed the value to two.
• 03:17 Then I can run the whole thing out.
• 03:18 So that looks okay.
• 03:20 It's kinda interesting.
• 03:20 Now what would happen if I ran it now?
• 03:25 We'll have to choose the copyright macro, and it says I'm gonna change,
• 03:28 you'll notice it is changed two.
• 03:31 Why? Because my selection right now has two
• 03:33 columns more run of those.
• 03:36 In every changes again because it has always been two column.
• 03:39 That's kind of interesting facts as well.
• 03:41 So this is how this can actually help us when we are debugging,
• 03:44 because we can see what's actually happening in this particular blocks.
• 03:47 Now the next part that I would like to do is I would like us to use a slightly
• 03:50 different version of this watch as well.
• 03:52 Let's do a different test.
• 03:53 Let's say I'm okay if it shows up with one column.
• 03:57 But I'd like to break only when the column count goes greater than one.
• 04:03 Cuz I've got one column right here.
• 04:05 So, if I run it now, say copyright it
• 04:11 stops where it change it's value to two, two greater than one is actually two.
• 04:17 And I think that's great but what value actually is it?
• 04:20 And a good way to find out is to go back and the add the original watch.
• 04:24 Lets do that.
• 04:25 We'll go right click, we'll say add watch.
• 04:27 And we'll go with RNG.COLUMNS.COUNT.
• 04:30 We'll just use a watch expression here.
• 04:34 We'll say okay, and there we go, rng.columns.count.
• 04:38 So if I had set up a variable to hold this,
• 04:41 it would show up in the locals window nice and easily.
• 04:44 But because I haven't, I can actually essentially use the watch window to
• 04:47 actually build the same kind of a variable thing into play that I can watch.
• 04:52 When it's done, and I hit run all of this stuff goes out of scope the watches
• 04:56 are still there but and I'll stick around, so when I go and actually run this again
• 05:00 and once again it'll stop in the figure case and say the columns are greater than
• 05:03 one because you actually have two calls in your selection now, that's all good but
• 05:08 I can actually see all those individual components which is kind of cool.
• 05:12 So it's another useful tool to actually help you get to the bottom of
• 05:15 why things are changing on you when you may not expect it

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