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iOS

Posted by Raphael Walser
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Raphael Walser
iOS Development Techdegree Student 4,569 Points

Unbinding the text of a Textfield and convert it to Double

I want to use a Text Fields "text" property (optional string) and turn it into a double to then do some calculations on it. Would the following be considered the correct (best practice) way to do this? :

    if let text = amountField.text, let number = Double(text) {
        tipCalc.total = number
    } else {
        tipCalc.total = 0.0
    }

Or is there a better way to do the same?

1 Answer

Raphael Walser
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Raphael Walser
iOS Development Techdegree Student 4,569 Points
Raphael Walser
.a{fill-rule:evenodd;}techdegree
Raphael Walser
iOS Development Techdegree Student 4,569 Points

I had tried that but it gives me the error:

Value of optional type 'String?' not unwrapped: did you mean to use '!' or '?'?

Or am I misunderstanding something here?

Zachary Betz
Zachary Betz
10,413 Points
Zachary Betz
Zachary Betz
10,413 Points

Was using an online Swift compiler, so was not able to verify that code against an actual UITextField. From reading up on it, it looks like your original post is the shortest way to do it.