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While debugging using logs and trace
points works well for simple scenarios,

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in more complex scenarios you'll probably
find this technique to be cumbersome.

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This is where breakpoints save the day.

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So what exactly is a breakpoint?

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A breakpoint is a way to indicate
that code execution should be

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paused at a specified place.

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When a break point is set, and
the code is run with the debugger.

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Execution of the code is suspended
right before the line of code

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associated with
the breakpoint is executed.

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We can set many breakpoints
throughout the code base.

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Later, we'll discover
how we can easily manage

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all the break points
set in our application.

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In this video, we'll set breakpoints that
will suspend the execution of the code and

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allow us to inspect and
modify the state of the application.

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Let's set a breakpoint right here
before we go into this while loop.

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Now, let's run the debugger.

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As you can see, the program has paused
before printing out the menu options.

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Now, we can step through the code
line by line if we want to.

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Because we're in the debugger, we now have
a bunch more buttons here on the toolbar.

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We have Show Next Statement,
Step Into, Step Over, and Step Out.

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We also have Restart and Stop here.

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Step into, let's say step into any
methods that are on the current line.

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In this case, we have the prompt method.

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So if we click Step Into, we'll go into
the prompt method cooking step into

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when there isn't a method to step into or
just step us over the next line of code.

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If we don't want to step into a method,
we can click the Step Over button.

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Let's say we don't want to
go into the display method,

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I'll click the step over button.

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The display method still runs like normal,

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but the debugger didn't
pause inside of it.

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And I'll click step over
when I get to CLI.Prompt.

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As you can see the CLI.prompt
method was called and

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I'm prompted to select an option.

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I'll select one here.

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Now, we're at the next line.

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We can run the rest of this prompt
method without pausing by clicking

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the step out button.

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This step says out of
the current method and

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now we're back where
menu.prompt was called.

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We might be looking around the code
while the debugger is paused.

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So if we ever lose track of where the
debugger is paused we can click the show

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next state button and we're brought back
to where the yellow arrow is right here.

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Also, we can click the Continue button
to run until another breakpoint.

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We can also have the program restart or
stop it completely.

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Breakpoints don't have to
be set on entire lines.

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A good example of this is when setting
a breakpoint on an auto property

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where the getter and
setter are on the same line.

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By default if we click to create
a breakpoint on the Name property

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only the getter is highlighted here.

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This means this breakpoint will
only be hit when getting the value

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of the name property.

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If we were to run this right now,

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this breakpoint would not be hit when
setting the value of the name property.

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However, sometimes we want to
pause before a property is set,

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we can do that by first highlighting
the set statement, right clicking,

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going down to Breakpoint and
clicking Insert Breakpoint.

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We now have two breakpoints on this line,
one on the getter and one on the setter.

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This trick is also helpful when
setting breakpoints on lines that may

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have multiple expressions in them such as

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ternary IF statements that
are written on a single line.