/**判断是否为字母+数字*/

    class func isLetterWithDigital(_ string:String) ->Bool{

         let numberRegex:NSPredicate=NSPredicate(format:"SELF MATCHES %@","^.*[0-9]+.*$")

         let letterRegex:NSPredicate=NSPredicate(format:"SELF MATCHES %@","^.*[A-Za-z]+.*$")

         if numberRegex.evaluate(with: string) && letterRegex.evaluate(with: string){

                return true

          }else{

                return false

          }

    }