如何在其创建的函数之外使用变量

Question

I am trying to figure out how I can use a variable outside of the function it was created in without using return. Example:

import UIKit
var Finalvar = "test"
func test(var1: String) {
    var Finalvar = var1

}
test(var1: "Done")
print(Finalvar)

as output I get "test" instead of "done", how can I change that?

Answer 1

Finalvar is not Finalvar

The global variable Finalvar and the local variable Finalvar are two different objects.

If you declare a local variable with the same name as a global variable the global variable is hidden.

Remove the var keyword in the function

var finalVar = "test"

func test(var1: String) {
    finalVar = var1

}
test(var1: "Done")
print(finalVar)

In a class or struct you can use self to indicate to access the property.

self.finalVar = var1

Note : Variable (and function) names are supposed to start with a lowercase letter.

Answer 2

You are declaring a new Finalvar again in your func test() , just leave out the declaration out in your function. The code below should work:

import UIKit
var finalVar = "test"
func test(var1: String) {
   finalVar = var1

}
test(var1: "Done")
print(finalVar)

One additional important thing -> please begin your variables with lowercase instead of a capital letter