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

完美的正则表达式,如谷歌电子邮件

"^[A-Z0-9a-z][a-zA-Z0-9_.-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,}"

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)
        }
    }

这是Swift 2.0 - 2.2的更新版本

 var isEmail: Bool {
    do {
        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.firstMatchInString(self, options: NSMatchingOptions(rawValue: 0), range: NSMakeRange(0, self.characters.count)) != nil
    } catch {
        return false
    }
}

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
    }
}

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
}

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。