如何检查一个字符串是否包含一个int？ -Swift

Question

我需要知道字符串是否包含 Int 以确保用户输入的名称是有效的全名，为此，我需要让用户只输入字符，或者确保用户输入的字符串中没有整数。感谢所有的帮助。

Answer 1

您需要通过包装其 nsRegularExpression

来欺骗 Swift 使用 Regex

class Regex {
  let internalExpression: NSRegularExpression
  let pattern: String

  init(_ pattern: String) {
    self.pattern = pattern
    var error: NSError?
    self.internalExpression = NSRegularExpression(pattern: pattern, options: .CaseInsensitive, error: &error)
  }

  func test(input: String) -> Bool {
    let matches = self.internalExpression.matchesInString(input, options: nil, range:NSMakeRange(0, countElements(input)))
    return matches.count > 0
  }

}

if Regex("\d/").test("John 2 Smith") {
  println("has a number in the name")
}

我从 http://benscheirman.com/2014/06/regex-in-swift/

那里得到这些

Answer 2

您可以将 Foundation 方法与 Swift 字符串一起使用，这就是您应该在此处执行的操作。 NSString 已内置使用 NSCharacterSet 的方法来检查是否存在某些类型的字符。这很好地转换为 Swift:

var str = "Hello, playground1"

let decimalCharacters = CharacterSet.decimalDigits

let decimalRange = str.rangeOfCharacter(from: decimalCharacters)

if decimalRange != nil {
    print("Numbers found")
}

如果您有兴趣限制可以输入的内容，您应该实施 UITextFieldDelegate 和方法 textField(_:shouldChangeCharactersIn:replacementString:) 以防止人们首先输入这些字符。

Answer 3

我现在使用这个方法来检查字符串是否包含数字

func doStringContainsNumber( _string : String) -> Bool{

        let numberRegEx  = ".*[0-9]+.*"
        let testCase = NSPredicate(format:"SELF MATCHES %@", numberRegEx)
        let containsNumber = testCase.evaluateWithObject(_string)

        return containsNumber
        }

如果您的字符串包含数字，它将 return 为真，否则为假。希望对你有帮助

Answer 4

if (ContainsNumbers(str).count > 0)
{
    // Your string contains at least one number 0-9
}

func ContainsNumbers(s: String) -> [Character]
{
    return s.characters.filter { ("0"..."9").contains([=10=])}
}

Answer 5

        //Swift 3.0 to check if String contains numbers (decimal digits):


    let someString = "string 1"
    let numberCharacters = NSCharacterSet.decimalDigits

    if someString.rangeOfCharacter(from: numberCharacters) != nil
    { print("String contains numbers")}
    else if someString.rangeOfCharacter(from: numberCharacters) == nil
    { print("String doesn't contains numbers")}

Answer 6

Swift 2.3。版本有效。

extension String
{
    func containsNumbers() -> Bool
    {
        let numberRegEx  = ".*[0-9]+.*"
        let testCase     = NSPredicate(format:"SELF MATCHES %@", numberRegEx)
        return testCase.evaluateWithObject(self)
    }
}

用法：

//guard let firstname = textField.text else { return }
    let testStr1 = "lalalala"
    let testStr2 = "1lalalala"
    let testStr3 = "lal2lsd2l"

    print("Test 1 = \(testStr1.containsNumbers())\nTest 2 = \(testStr2.containsNumbers())\nTest 3 = \(testStr3.containsNumbers())\n")

Answer 7

简单 Swift 4 版本使用 rangeOfCharacter 方法 String class:

    let numbersRange = stringValue.rangeOfCharacter(from: .decimalDigits)
    let hasNumbers = (numbersRange != nil)

Answer 8

let numericCharSet = CharacterSet.init(charactersIn: "1234567890")

let newCharSet = CharacterSet.init(charactersIn: "~`@#$%^&*(){}[]<>?")

let sentence = "Tes#ting4 @Charact2er1Seqt"

if sentence.rangeOfCharacter(from: numericCharSet) != nil {
    print("Yes It,Have a Numeric")
    let removedSpl = sentence.components(separatedBy: newCharSet).joined()
    print(sentence.components(separatedBy: newCharSet).joined())
    print(removedSpl.components(separatedBy: numericCharSet).joined())
} 

else {
    print("No")
}

Answer 9

//A function that checks if a string has any numbers
func stringHasNumber(_ string:String) -> Bool {
    for character in string{
        if character.isNumber{
            return true
        }
    }
    return false
}

/// Check stringHasNumber function
stringHasNumber("mhhhldiddld")
stringHasNumber("kjkdjd99900")

如何检查一个字符串是否包含一个int？ -Swift

How to check if a string contains an int? -Swift

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int

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