[String+Extensions] #string

String+Extensions.swift

extension String {
/// Remove all whitespaces from the string
	mutating func withoutWhitespaces() {
		let array = components(separatedBy: .whitespaces)
		self = array.joined()
	}

/// Check if a string consists only of characters from a specified ChatacterSet
	func hasOnly(charsFrom charSet: CharacterSet) -> Bool {
		for char in unicodeScalars {
			if !charSet.contains(char) {
				return false
			}
		}
		return true
	}
/// Check if a string contains only valid for url host characters
	func isValidHost() -> Bool {
		if isEmpty {
			return false
		}
		if !hasOnly(charsFrom: .urlHostAllowed) {
			return false
		}
		return true
	}
 /// Generate a random string
      static func randomString(length: Int) -> String {
        
        let letters : NSString = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
        let len = UInt32(letters.length)
        
        var randomString = ""
        
        for _ in 0 ..< length {
            let rand = arc4random_uniform(len)
            var nextChar = letters.character(at: Int(rand))
            randomString += NSString(characters: &nextChar, length: 1) as String
        }
        
        return randomString
    }
}