ios - 单击时如何更改标签中的字母？

Question

点击时如何更改标签中的字母？ 2 个用于较小字母或大写字母的按钮。

当我们单击小写字母时，标签会更改为小写字母，反之亦然。

如何做到这一点？我尝试了一些代码，但我被卡住了。

let ABC = ["A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z"]

var str: Character = "Z"

//@IBOutlet weak var capitalABC: UIButton!
// @IBOutlet weak var smallac: UIButton!
// @IBOutlet weak var Abclbl: UILabel!
@IBOutlet weak var Abclbl: UILabel!
// @IBOutlet weak var Abclbl: Le!

override func viewDidLoad() {
    super.viewDidLoad()

    Abclbl.text = ABC[0]

    // Do any additional setup after loading the view.
}

func ABCPre(sender: AnyObject) {
    if Abclbl.text == "a"
    {
        print("Do nothing")
    }
    else
    {
        let preVal = self.Abclbl.text!
        var inde = ABC.indexOf(preVal)
        inde = inde! - 1
        let get = ABC[inde!]
        Abclbl.text = get
        alphReocg(Abclbl.text!)
    }
}

func ABCNext(sender: AnyObject) {
    //let str: String = "Z"
    if Abclbl.text! == String(str)
    {
        print("Do nothing")
    }
    else
    {
        let preVal = self.Abclbl.text!
        var inde = ABC.indexOf(preVal)
        inde = inde! + 1
        let get = ABC[inde!]
        Abclbl.text = get
        alphReocg(Abclbl.text!)
    }
}

Answer 1

如果您需要简单地将文本转换为小写和大写，然后在按钮单击方法中转换字符串，如下所示

为swift 3.0首次导入基础

import Foundation

然后在按钮中单击操作

 func uppercase(sender: AnyObject) {

    var title = "Text That you need to convert " 
    title.uppercased() // "TEXT THAT YOU NEED TO CONVERT"
}

对于小写

   func lowercase(sender: AnyObject) {

    var title = "Text That you need to convert" 
    title.lowercased() // "text that you need to convert"
}