CODEWITHSUNDEEP
stringswiftnumbersinttextfield
Joe
Joe

Reputation: 847

Xcode 6.1 & Swift - textField input string to integer for basic math

I am slowly understanding things in swift, I am coming for a javascript background so it is somewhat familiar.

However variables are urking me.

in JS a variable can be

var varName = 1;     //Number
var varName2 = "petey" //String

var conCat = varname + varName2; //  1petey

however in swift String vars and In var are troubling me. All I want to do is capture decimal number from user input from multiple "textField" sources and store that data to variable (which i already have setup) I need to concatinate a few of them with + then do basic math with the data in the variables with * and /.

How do I make the textFeld only capture?int or how do I convert text field strings to numbers, e.g. int?

Upvotes: 0

Views: 11439

Answers (3)

Roman_Fire
Roman_Fire

Reputation: 1

Use the function in swift inputmethod.intValue(); if any text is entered then it returns with a 0.

Upvotes: 0

Dhruv Ramani
Dhruv Ramani

Reputation: 2643

The data send from the textField is String. There are multiple ways to convert an Int to a String.

var a:String="\(2+3)" //"5"

And to concatenate a String to Int :

var b:String="Hello "+"\(3*4)" //"Hello 12"

And to Convert a String to an Int from a textField:

var b:Int=textField.text.toInt()

Upvotes: 0

Sebastian
Sebastian

Reputation: 8154

A UITextField contains a String, not an Int, so you have to convert it, e.g.

let number : Int? = textField.text.toInt()

So, there actually is a method to convert from String to Int built-in in Swift. Beware, that it returns an optional, because the conversion may fail. So you have to check for nil before you use the variable.

For your other question, take a look at e.g. UITextField - Allow only numbers and punctuation input/keypad. Basically, you will have to adapt UITextField and filter it, once there are new entries. On iOS it might be easier, because you can show a numbers-only keyboard.

Upvotes: 1

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