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We can change the way our code executes without stopping the debugger.
Let's delete all the breakpoints
we have so far and
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I'll show you one of my favorite
ways to start the debugger.
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We can right-click on the line of
code that we want to break at and
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click Run To Cursor.
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The debugger starts and
runs to that point.
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Another neat but
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dangerous trick is to set the next
line of code that should be executed.
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Let's say we're here and
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we want to just skip to the add song
method without calling menu dot prompt.
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That way we don't have
to type in the console.
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I can just drag the yellow
arrow here down to this line.
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This sets the next line
of code to be executed.
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Unlike using the Step Over button,
the code between where we were and
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where we are now isn't executed.
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So the Menu.Prompt
method was never called.
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As you can imagine,
this can cause some problems.
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Let's step into the add song method.
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Again, let's say we don't want to
have to run these prompt methods.
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Another way to set the next line of code
to execute is to right click on the line
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and click Set Next Statement.
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Now, we just jump to past these
lines here without executing them.
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Hovering over song name and
artist shows us that they're both null.
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That could be bad.
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Never fear,
we can just set their values here instead.
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Now, if I click the step over button, this
song will be added to our list of songs.
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Let's jump past the end of the loop and
skip this prompt.
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Now, I can use the Step Out button
to bring us back to the main method.
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We can also go backward.
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Let's say we want to go
back to see this prompt.
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We can just drag the yellow arrow up here.
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And then, press the Continue button.
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We usually want to see how the code
runs without us interfering too much.
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So using these features
can be problematic.
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But as you can see,
it can also be quite helpful.
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You can also use this trick if
you're stepping through the code and
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you identify what might
be causing the bug.
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You can experiment with different and
variable values and
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ways to the code by using these
features of the debugger.
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In debuggers without these features,
you have to stop change the code and
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then rerun it.
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Some it can take a long time to
get back to where the problem is
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only to find out that the bug isn't fixed.
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Visual Studio has another great debugging
feature that allows us to actually make
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substantial changes in the code without
actually having to stop the debugger and
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start all over again.
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This feature is called Edit and Continue.
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Edit and Continue is a feature
that can be enabled or
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disabled in Visual Studio's options.
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To make sure that it's enabled,
go to the Tools menu and click Options.
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On the left side of the dialog, scroll
down to Debugging, then scroll down to
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the Edit and Continue section down
here Here we see that it's checked.
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We can't change the value of this option
while Visual Studio is in debugging mode.
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Let's set a breakpoint
back here on line 21.
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I'll enter an option so
that we get to the switch statement.
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Let's say that at this
point while debugging,
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we notice that we accidentally
had these two methods swapped.
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We can fix this right now
without stopping the debugger.
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We can move the AddSong method down here.
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And we can move the DisplaySongList
method up here.
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Now, if we step through this code using
step into, you'll notice that we now enter
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the DisplaySongList method
instead of the AddSong method.
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This is really handy
when we're debugging and
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notice things that we can fix right away.
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