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。
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
}
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}$"
let emailPred = NSPredicate(format:"SELF MATCHES %@", emailRegEx)
return emailPred.evaluate(with: self)
}
}
下面是我们如何为它编写测试用例。
XCTAssertFalse("ab1234@.nyu.edu".isValidEmail())
XCTAssertTrue("valid_email@email.com".isValidEmail())
在Swift 5.7中，在Regex类的帮助下，我们可以以简单有效的方式验证电子邮件地址
private func isValidEmail(_ email: String) -> Bool {
guard let emailRegex = try? Regex("[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,64}")
else { return false }
return email.firstMatch(of: emailRegex) != nil
}
我们还可以使用属性包装器来提高效率:
@propertyWrapper
struct EmailPropertyWrapper {
private var _value: String
var wrappedValue: String {
get { return isValidEmail(_value) ? _value : String() }
set { _value = newValue }
}
init(email: String) {
_value = email
}
private func isValidEmail(_ email: String) -> Bool {
guard let emailRegex = try? Regex("[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,64}")
else { return false }
return email.firstMatch(of: emailRegex) != nil
}
}
struct User {
var name: String
@EmailPropertyWrapper var email: String
func validateProperty() -> Bool {
if name.isEmpty || email.isEmpty { return false }
return true
}
}
let user = User(name: "Sy", email: .init(email: "wwdc@icloud.com"))
print(user.validateProperty())
创建简单的扩展:
extension NSRegularExpression {
convenience init(pattern: String) {
try! self.init(pattern: pattern, options: [])
}
}
extension String {
var isValidEmail: Bool {
return isMatching(expression: NSRegularExpression(pattern: "^[A-Z0-9a-z\\._%+-]+@([A-Za-z0-9-]+\\.)+[A-Za-z]{2,4}$"))
}
//MARK: - Private
private func isMatching(expression: NSRegularExpression) -> Bool {
return expression.numberOfMatches(in: self, range: NSRange(location: 0, length: characters.count)) > 0
}
}
例子:
"b@bb.pl".isValidEmail //true
"b@bb".isValidEmail //false
你可以扩展以下扩展到任何你需要的:isValidPhoneNumber, isValidPassword等…
