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JavaScript DOM Scripting By Example Adding and Removing Names Registering Names

Posted by Jack Dolitsky
Jack Dolitsky
4,187 Points

const variables question

why are the const variables inside the event handler and not at the top?

2 Answers

Ella Ruokokoski
Ella Ruokokoski
20,881 Points
Ella Ruokokoski
Ella Ruokokoski
20,881 Points

Because you do not need to use those const variables anywhere else in the app, only the event handler needs those variables so they can be declared inside the handler.

Clinton Hays
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.a{fill-rule:evenodd;}techdegree seal-36
Clinton Hays
Front End Web Development Techdegree Graduate 18,156 Points
Clinton Hays
.a{fill-rule:evenodd;}techdegree seal-36
Clinton Hays
Front End Web Development Techdegree Graduate 18,156 Points

Hey Jack Dolitsky,

Ella Ruokokoski is right. We don't declare them at the top since we don't need to access them globally. In addition, declaring them in the function makes sure that we don't accidentally access them elsewhere in the file. Lastly, declaring the variables only in the function means that we can reuse that variable name elsewhere if needed. For example, if we have another function that uses a text input value, we can use the variable name 'text' in that function.

Hope that makes sense. Happy coding!