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

在Swift 4.2和Xcode 10.1中

//Email validation
func isValidEmail(email: String) -> Bool {
    let emailRegex = "[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,4}"
    var valid = NSPredicate(format: "SELF MATCHES %@", emailRegex).evaluate(with: email)
    if valid {
        valid = !email.contains("Invalid email id")
    }
    return valid
}

//Use like this....
let emailTrimmedString = emailTF.text?.trimmingCharacters(in: .whitespaces)
if isValidEmail(email: emailTrimmedString!) == false {
   SharedClass.sharedInstance.alert(view: self, title: "", message: "Please enter valid email")
}

如果你想使用SharedClass。

//This is SharedClass
import UIKit
class SharedClass: NSObject {

static let sharedInstance = SharedClass()

//Email validation
func isValidEmail(email: String) -> Bool {
    let emailRegex = "[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,4}"
    var valid = NSPredicate(format: "SELF MATCHES %@", emailRegex).evaluate(with: email)
    if valid {
        valid = !email.contains("Invalid email id")
    }
    return valid
}

private override init() {

}
}

并调用这样的函数....

if SharedClass.sharedInstance. isValidEmail(email: emailTrimmedString!) == false {
   SharedClass.sharedInstance.alert(view: self, title: "", message: "Please enter correct email")
   //Your code here
} else {
   //Code here
}

其他回答

作为String类扩展

斯威夫特4

extension String {
    func isValidEmail() -> Bool {
        // here, `try!` will always succeed because the pattern is valid
        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: NSRange(location: 0, length: count)) != nil
    }
}

使用

if "rdfsdsfsdfsd".isValidEmail() {

}

这里有很多正确答案,但许多“正则表达式”是不完整的,可能会发生像“name@domain”这样的电子邮件结果是有效的电子邮件,但它不是。这里是完整的解决方案:

extension String {

    var isEmailValid: Bool {
        do {
            let regex = try NSRegularExpression(pattern: "(?:[a-z0-9!#$%\\&'*+/=?\\^_`{|}~-]+(?:\\.[a-z0-9!#$%\\&'*+/=?\\^_`{|}~-]+)*|\"(?:[\\x01-\\x08\\x0b\\x0c\\x0e-\\x1f\\x21\\x23-\\x5b\\x5d-\\x7f]|\\\\[\\x01-\\x09\\x0b\\x0c\\x0e-\\x7f])*\")@(?:(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?|\\[(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?|[a-z0-9-]*[a-z0-9]:(?:[\\x01-\\x08\\x0b\\x0c\\x0e-\\x1f\\x21-\\x5a\\x53-\\x7f]|\\\\[\\x01-\\x09\\x0b\\x0c\\x0e-\\x7f])+)\\])", options: .CaseInsensitive)
            return regex.firstMatchInString(self, options: NSMatchingOptions(rawValue: 0), range: NSMakeRange(0, self.characters.count)) != nil
        } catch {
            return false
        }
    }
}

在Swift 5.7中,在Regex类的帮助下,我们可以以简单有效的方式验证电子邮件地址

private func isValidEmail(_ email: String) -> Bool {
      guard let emailRegex = try? Regex("[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,64}")  
      else { return false }
      return email.firstMatch(of: emailRegex) != nil
   }

我们还可以使用属性包装器来提高效率:

@propertyWrapper
struct EmailPropertyWrapper {
  private var _value: String
  var wrappedValue: String {
    get { return isValidEmail(_value) ? _value : String() }
    set { _value = newValue }
  }
  
  init(email: String) {
    _value = email
  }

  private func isValidEmail(_ email: String) -> Bool {
      guard let emailRegex = try? Regex("[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,64}")  
      else { return false }
      return email.firstMatch(of: emailRegex) != nil
   }
}

struct User {
  var name: String
  @EmailPropertyWrapper var email: String
  
  func validateProperty() -> Bool {
    if name.isEmpty || email.isEmpty { return false }
    return true
  }
}

let user = User(name: "Sy", email: .init(email: "wwdc@icloud.com"))

print(user.validateProperty())

编辑,针对Swift 3更新:

func validateEmail(enteredEmail: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: enteredEmail)

}

Swift 2的原始答案:

func validateEmail(enteredEmail: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.evaluateWithObject(enteredEmail)

}

它工作得很好。

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 
    {

    }