有人知道如何在Swift中验证电子邮件地址吗?我找到了这个代码:

- (BOOL) validEmail:(NSString*) emailString {

    if([emailString length]==0){
        return NO;
    }

    NSString *regExPattern = @"[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,4}";

    NSRegularExpression *regEx = [[NSRegularExpression alloc] initWithPattern:regExPattern options:NSRegularExpressionCaseInsensitive error:nil];
    NSUInteger regExMatches = [regEx numberOfMatchesInString:emailString options:0 range:NSMakeRange(0, [emailString length])];

    NSLog(@"%i", regExMatches);
    if (regExMatches == 0) {
        return NO;
    } else {
        return YES;
    }
}

但我无法翻译成斯威夫特。


当前回答

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
    }
}

其他回答

下面是两个投票最多的答案与正确的正则表达式的融合:一个使用谓词的字符串扩展,因此您可以调用String . isemail

    extension String {
        var isEmail: Bool {
           let emailRegEx = "[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,20}"            
           let emailTest  = NSPredicate(format:"SELF MATCHES %@", emailRegEx)
           return emailTest.evaluateWithObject(self)
        }
    }

Swift 4.2的使用

extension String {
    func isValidEmail() -> Bool {
        let regex = try? NSRegularExpression(pattern: "^(((([a-zA-Z]|\\d|[!#\\$%&'\\*\\+\\-\\/=\\?\\^_`{\\|}~]|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])+(\\.([a-zA-Z]|\\d|[!#\\$%&'\\*\\+\\-\\/=\\?\\^_`{\\|}~]|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])+)*)|((\\x22)((((\\x20|\\x09)*(\\x0d\\x0a))?(\\x20|\\x09)+)?(([\\x01-\\x08\\x0b\\x0c\\x0e-\\x1f\\x7f]|\\x21|[\\x23-\\x5b]|[\\x5d-\\x7e]|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])|(\\([\\x01-\\x09\\x0b\\x0c\\x0d-\\x7f]|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}]))))*(((\\x20|\\x09)*(\\x0d\\x0a))?(\\x20|\\x09)+)?(\\x22)))@((([a-zA-Z]|\\d|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])|(([a-zA-Z]|\\d|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])([a-zA-Z]|\\d|-|\\.|_|~|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])*([a-zA-Z]|\\d|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])))\\.)+(([a-zA-Z]|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])|(([a-zA-Z]|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])([a-zA-Z]|\\d|-|_|~|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])*([a-zA-Z]|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])))\\.?$", options: .caseInsensitive)
        return regex?.firstMatch(in: self, options: [], range: NSMakeRange(0, self.count)) != nil
    }
    func isValidName() -> Bool{
        let regex = try? NSRegularExpression(pattern: "^[\\p{L}\\.]{2,30}(?: [\\p{L}\\.]{2,30}){0,2}$", options: .caseInsensitive)

        return regex?.firstMatch(in: self, options: [], range: NSMakeRange(0, self.count)) != nil
    } }

和使用

if (textField.text?.isValidEmail())! 
    {
      // bla bla
    }
else 
    {

    }

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 ...
        }
    }
}

或者你可以扩展可选文本UITextField:

使用方法:

if  emailTextField.text.isEmailValid() {
      print("email is valid")
}else{
      print("wrong email address")
}

扩展:

extension Optional where Wrapped == String {
    func isEmailValid() -> Bool{
        guard let email = self else { return false }
        let emailPattern = "[A-Za-z-0-9.-_]+@[A-Za-z0-9]+\\.[A-Za-z]{2,3}"
        do{
            let regex = try NSRegularExpression(pattern: emailPattern, options: .caseInsensitive)
            let foundPatters = regex.numberOfMatches(in: email, options: .anchored, range: NSRange(location: 0, length: email.count))
            if foundPatters > 0 {
                return true
            }
        }catch{
            //error
        }
        return false
    }
}

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
}