Pass Information to a Function2:19 with Guil Hernandez
You'll usually pass information to a function to change how the function works, using parameters.
Just like you're able to pass information like a message into prompt and alert, 0:00 you'll commonly pass information to a function to change how the function works. 0:05 To do this, 0:10 you add what's called a parameter inside the parentheses when creating a function. 0:10 So now let's change sayHello to a function that accepts a custom greeting and 0:15 displays it to the user. 0:21 First, I'll change the function name to 0:22 sayGreeting to better to describe the purpose of the function. 0:26 And this function will take one parameter, I'll call it greeting. 0:29 Then I'll pass greeting into alert, I'll simply copy and 0:35 paste it and replace Hello Wwith greeting. 0:40 And I'll combine it with response using a plus sign. 0:44 Now I wanna display a space and a comma between the greeting and name. 0:48 So I'll add them inside quotes 0:53 with a plus sign before and after this new set of quotes. 0:58 So the greeting parameter works just like a variable. 1:04 Notice how I'm using it inside my function, 1:07 just like any variable, like response, for example. 1:09 So now, each time I call this function, 1:13 it's going to expect information passed into it. 1:16 So right below the function, let's call sayGreeting. 1:19 And between the parentheses, I'll pass the string Good morning. 1:27 Passing information to a function call like this 1:33 is also called passing an argument to a function. 1:36 I'll give main.js a save. 1:39 Over in the browser, I'll refresh. 1:41 I'll type Guil into the box, click OK, and 1:45 it returns an alert with the message Good morning, Guil, cool. 1:49 Now if I go back to my program and change the message to Have a good day. 1:53 Refresh. 2:05 It now displays an alert with the message have a good day, Guil. 2:07 Good, so as you can see using parameters with functions makes them more flexible. 2:10 We can pass different values and get different results. 2:15
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