小编Dav*_*lla的帖子

我正在创建一个登录系统,我不希望在用户名字段中允许使用空格.我想阻止添加空格,而不是检查和验证字段.

因此,每次用户按空格键时,都不会发生任何事情.我怎样才能做到这一点？我见过Instagram这样做.

到目前为止这是我的代码:

import UIKit

class ViewController: UIViewController, UITextFieldDelegate {

    @IBOutlet weak var signUp: UIBarButtonItem!
    @IBOutlet weak var navBar: UINavigationBar!
    @IBOutlet weak var UsernameText: UITextField!


    override func viewDidLoad() {
        super.viewDidLoad()

             self.navigationController?.navigationBar.clipsToBounds = true
        UsernameText.attributedPlaceholder = NSAttributedString(string:"TypeYourUsername",
            attributes:[NSForegroundColorAttributeName: UIColor.whiteColor()])

        func textField(UsernameText: UITextField, shouldChangeCharactersInRange range: NSRange, replacementString string: String) -> Bool {
            if (string == " ") {
                return false
            }
            return true
        }
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

    override func …