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。
@JeffersonBe的答案是接近的，但如果字符串是“包含someone@something.com一个有效的电子邮件”，这不是我们想要的。下面是String上的一个扩展，它工作得很好(并且允许测试有效的phoneNumber和其他数据检测器来引导。
/// Helper for various data detector matches.
/// Returns `true` iff the `String` matches the data detector type for the complete string.
func matchesDataDetector(type: NSTextCheckingResult.CheckingType, scheme: String? = nil) -> Bool {
let dataDetector = try? NSDataDetector(types: type.rawValue)
guard let firstMatch = dataDetector?.firstMatch(in: self, options: NSRegularExpression.MatchingOptions.reportCompletion, range: NSRange(location: 0, length: length)) else {
return false
}
return firstMatch.range.location != NSNotFound
// make sure the entire string is an email, not just contains an email
&& firstMatch.range.location == 0
&& firstMatch.range.length == length
// make sure the link type matches if link scheme
&& (type != .link || scheme == nil || firstMatch.url?.scheme == scheme)
}
/// `true` iff the `String` is an email address in the proper form.
var isEmail: Bool {
return matchesDataDetector(type: .link, scheme: "mailto")
}
/// `true` iff the `String` is a phone number in the proper form.
var isPhoneNumber: Bool {
return matchesDataDetector(type: .phoneNumber)
}
/// number of characters in the `String` (required for above).
var length: Int {
return self.characters.count
}
更新答案@Arsonik对Swift 2.2的回答，使用比其他提供的解决方案更少的冗长代码:
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?.firstMatchInString(self, options: [], range: NSMakeRange(0, self.characters.count)) != nil
}
}
我唯一添加到响应列表的是，对于Linux, NSRegularExpression不存在，它实际上是RegularExpression
func isEmail() -> Bool {
let patternNormal = "[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,6}"
#if os(Linux)
let regex = try? RegularExpression(pattern: patternNormal, options: .caseInsensitive)
#else
let regex = try? NSRegularExpression(pattern: patternNormal, options: .caseInsensitive)
#endif
return regex?.firstMatch(in: self, options: [], range: NSMakeRange(0, self.characters.count)) != nil
在macOS和Ubuntu上都能成功编译。
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())
以上大多数正则表达式示例在电子邮件存在基本问题时都无法捕获错误。例如
h..1@nyu.edu -连续的点
ab1234@.nyu.edu - @后面的点
a.bcdnle12.@email.com - @前的点
.abc@email.com -以一个点开始
这是一个字符串扩展，我使用了更严格的规则使用正则表达式。
extension String {
func isValidEmail() -> Bool {
let emailRegEx = "^(?!\\.)([A-Z0-9a-z_%+-]?[\\.]?[A-Z0-9a-z_%+-])+@[A-Za-z0-9-]{1,20}(\\.[A-Za-z0-9]{1,15}){0,10}\\.[A-Za-z]{2,20}$"
let emailPred = NSPredicate(format:"SELF MATCHES %@", emailRegEx)
return emailPred.evaluate(with: self)
}
}
下面是我们如何为它编写测试用例。
XCTAssertFalse("ab1234@.nyu.edu".isValidEmail())
XCTAssertTrue("valid_email@email.com".isValidEmail())
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
}
}
