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。
我改进了@Azik的答案。我允许使用准则允许的更多特殊字符，并返回一些无效的额外边缘情况。
小组认为这里只允许本地部分的。_%+-是不正确的。参见@Anton Gogolev对这个问题的回答或参见下文:
The local-part of the email address may use any of these ASCII
characters:
uppercase and lowercase Latin letters A to Z and a to z;
digits 0 to 9;
special characters !#$%&'*+-/=?^_`{|}~;
dot ., provided that it is not the first or last character unless quoted, and provided also that it does not appear consecutively unless quoted (e.g.
John..Doe@example.com is not allowed but "John..Doe"@example.com is
allowed);
space and "(),:;<>@[\] characters are allowed with
restrictions (they are only allowed inside a quoted string, as
described in the paragraph below, and in addition, a backslash or
double-quote must be preceded by a backslash);
comments are allowed
with parentheses at either end of the local-part; e.g.
john.smith(comment)@example.com and (comment)john.smith@example.com
are both equivalent to john.smith@example.com;
我使用的代码将不允许限制性的特殊字符，但将允许比这里的大多数答案更多的选项。我更喜欢更宽松的验证，而不是谨慎的错误。
if enteredText.contains("..") || enteredText.contains("@@")
|| enteredText.hasPrefix(".") || enteredText.hasSuffix(".con"){
return false
}
let emailFormat = "[A-Z0-9a-z.!#$%&'*+-/=?^_`{|}~]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,64}"
let emailPredicate = NSPredicate(format:"SELF MATCHES %@", emailFormat)
return emailPredicate.evaluate(with: enteredText)
我会使用npredicate:
func isValidEmail(_ email: String) -> Bool {
let emailRegEx = "[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,64}"
let emailPred = NSPredicate(format:"SELF MATCHES %@", emailRegEx)
return emailPred.evaluate(with: email)
}
对于Swift 3.0之前的版本:
func isValidEmail(email: String) -> Bool {
let emailRegEx = "[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,64}"
let emailPred = NSPredicate(format:"SELF MATCHES %@", emailRegEx)
return emailPred.evaluate(with: email)
}
对于Swift 1.2之前的版本:
func isValidEmail(email: String) -> Bool {
let emailRegEx = "[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,64}"
if let emailPred = NSPredicate(format:"SELF MATCHES %@", emailRegEx) {
return emailPred.evaluateWithObject(email)
}
return false
}
下面是一个基于rangeOfString的方法:
class func isValidEmail(testStr:String) -> Bool {
let emailRegEx = "[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,64}"
let range = testStr.rangeOfString(emailRegEx, options:.RegularExpressionSearch)
return range != nil
}
备注:更新TLD长度。
下面是符合RFC 5322的电子邮件的最终RegEx，请注意，最好不要使用它，因为它只检查电子邮件地址的基本语法，而不检查顶级域是否存在。
(?:[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[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])?
| \[(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}
(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?|[a-z0-9-]*[a-z0-9]:
(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21-\x5a\x53-\x7f]
| \\[\x01-\x09\x0b\x0c\x0e-\x7f])+)
\])
有关电子邮件regex的更完整信息，请参阅Regular-Expressions.info。
注意，在Objective-C或Swift等语言中没有转义。
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())
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() {
}
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。
