//Email validation
func validateEmail(enterEmail:String) -> Bool{
    let emailFormat = "[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,64}"
    let emailPredicate = NSPredicate(format:"SELF MATCHES %@",emailFormat)
    return emailPredicate.evaluate(with:enterEmail)
}

100%工作和测试

Swift 5 -可伸缩的验证层

使用此层，您将轻松地在任何文本字段上获得惊人的验证。

只需遵循以下流程即可。

1. 添加这些枚举:

import Foundation

enum ValidatorType
{
    case email
    case name
    // add more cases ...
}

enum ValidationError: Error, LocalizedError
{
    case invalidUserName
    case invalidEmail
    // add more cases ...

    var localizedDescription: String
    {
        switch self
        {
        case .invalidEmail:
            return "Please kindly write a valid email"    
        case .invalidUserName:
            return "Please kindly write a valid user name"
        }
    }
}

2. 将此功能添加到String:

extension String
{
    // MARK:- Properties

    var isValidEmail: Bool
    {
        let emailFormat = "[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,64}"
        let emailPredicate = NSPredicate(format:"SELF MATCHES %@", emailFormat)
        return emailPredicate.evaluate(with: self)
    }

    // MARK:- Methods

    func validatedText(_ validationType: ValidatorType) throws
    {
        switch validationType
        {
            case .name:
                try validateUsername()
            case .email:
                try validateEmail()
        }
    }

    // MARK:- Private Methods

    private func validateUsername() throws
    {
        if isEmpty
        {
            throw ValidationError.invalidUserName
        }
    }

    private func validateEmail() throws
    {
        if !isValidEmail 
        {
            throw ValidationError.invalidEmail
        }

        // add more validations if you want like empty email
    }
}

3.添加以下功能到UITextField:

import UIKit

extension UITextField
{
    func validatedText(_ validationType: ValidatorType) throws
    {
        do
        {
            try text?.validatedText(validationType)
        }
        catch let validationError
        {
            shake()
            throw validationError
        }
    }

    // MARK:- Private Methods

    private func shake()
    {
        let animation = CABasicAnimation(keyPath: "position")
        animation.duration = 0.1
        animation.repeatCount = 5
        animation.fromValue = NSValue(cgPoint: CGPoint(x: center.x + 6, y: center.y))
        animation.toValue = NSValue(cgPoint: CGPoint(x: center.x - 6, y: center.y))
        layer.add(animation, forKey: "position")
    }
}

使用

import UIKit

class LoginVC: UIViewController
{
    // MARK: Outlets

    @IBOutlet weak var textFieldEmail: UITextField!

    // MARK: View Controller Life Cycle

    override func viewDidLoad()
    {
        super.viewDidLoad()
    }

    // MARK: Methods

    private func checkEmail() -> Bool
    {
        do
        {
            try textFieldEmail.validatedText(.email)
        }
        catch let error
        {
            let validationError = error as! ValidationError
            // show alert to user with: validationError.localizedDescription
            return false
        }

        return true
    }

    // MARK: Actions

    @IBAction func loginTapped(_ sender: UIButton)
    {
        if checkEmail()
        {
            let email = textFieldEmail.text!
            // move safely ...
        }
    }
}

我为输入验证设计了一个库，其中一个“模块”可以让你轻松地验证一堆东西…

例如，要验证一封电子邮件:

let emailTrial = Trial.Email
let trial = emailTrial.trial()

if(trial(evidence: "test@test.com")) {
   //email is valid
}

SwiftCop是图书馆…希望能有所帮助!

似乎也有用……

let regex = "[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,}"

func validate(email: String) -> Bool {
    let matches = email.rangeOfString(regex, options: .RegularExpressionSearch)
    if let _ = matches {
        return true
    }
    return false
}

对于Swift 3:

extension String {
    func isValidEmail() -> Bool {
        let regex = try? NSRegularExpression(pattern: "^[a-zA-Z0-9.!#$%&'*+/=?^_`{|}~-]+@[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?(?:\\.[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?)*$", options: .caseInsensitive)
        return regex?.firstMatch(in: self, options: [], range: NSMakeRange(0, self.characters.count)) != nil
    }
}

这是Swift 3的扩展

extension String {
    func isValidEmail() -> Bool {
        let emailRegex = "[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,64}"
        return NSPredicate(format: "SELF MATCHES %@", emailRegex).evaluate(with: self)
    }
}

就像这样使用它:

if yourEmailString.isValidEmail() {
    //code for valid email address
} else {
    //code for not valid email address
}