WEBVTT

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Here is our Wait method from earlier.

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It would be nice to be able to
specify how long it should pause for.

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We could do that by
passing in an argument.

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For example, we can pass at the number
of milliseconds to wait for.

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3,000 milliseconds will cause
it to wait for 3 seconds.

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But if we save this code and
try to run it,

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We get a compiler error, no overload for
method Wait takes 1 arguments.

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In other words,
a call to wait can accept an argument.

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We can give it to accept one
using method parameters.

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Here's a program that declares an Add
method that accepts two parameters and

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then another subtract method that
also accepts two parameters.

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A parameter is a special variable that
you declare at the start of a method.

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It's just like declaring a variable.

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You specify a type and
a name for the parameter.

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You can specify multiple parameters
by separating them with commas.

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Within the method body, you can access the
parameter just like you would a variable.

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In the Add method, we print the value
with the first parameter and

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then print the value of
the second parameter.

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Then we print the result of adding
the first and second parameter together.

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When a method takes parameters,

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you need to provide argument
values when calling that method.

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C# sets each parameter value
with the value in the argument.

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So this first argument to Add is going
to be the value that the first parameter

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gets set to.

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The second argument in the method
call is going to be the value that

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the second parameter gets set to.

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Let's save this and
try running it, with dotnet run.

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And you can see that it prints the value
of the first parameter, then the value

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of the second parameter, and
then the value of adding the two together.

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Let's try adding another column
with different arguments.

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So I'll call Add and
pass the first argument of 10.5 and

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the second argument of 7.2,
let's try saving that.

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And running it.

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And there we are, and
our first parameter is set to 10.5.

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Our second parameter to 7.2 and here's
the result of adding the two together.

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Let's try calling this subtract
method with a first argument of 9 and

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the second argument of 3.

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Let's save this and try running it.

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And here we are at the bottom, our first
parameter is set to 9, our second to 3,

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and here's the result of
subtracting 3 from 9.

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One last call, let's call Subtract
again with different arguments.

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21.3 and 7.1 save this.

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Run it?

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And there's the results of calling
Subtract with different arguments.

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Let's take what we've learned and
fix our Wait method.

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We want to be able to pass an argument to
it with the number of milliseconds that it

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should wait for.

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But right now we're getting
an error saying no overload for

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method Wait takes one arguments.

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That's because we haven't set any
parameters up in the definition for

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the Wait method.

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Let's go ahead and add one now and
see if that fixes it.

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So I'll add an int parameter because
this is going to accept an integer and

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we'll name it delay.

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I don't need to make any other changes to
the method except to take this hard coded

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3000 millisecond value and replace it
with the name of the delay parameter.

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Let me save this and we'll try running it.

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You can see it says waiting, it waits
three seconds and then it prints done.

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Let's try adding a call to wait with a
different argument and see if it waits for

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a different period of time.

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We'll say wait(1,000) milliseconds,
so 1 second.

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Save that.

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Try running it.

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And first, it waits for
one second, and prints done.

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Then it waits for
three seconds and prints done.

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So by adding a delay parameter to the
weight method definition, we were able to

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pass arguments to our calls to wait,
saying how long it should wait for.