extension String {

    func isTelNumber() -> Bool
    {
        let mobile = "^1(3[0-9]|5[0-35-9]|8[025-9])\\d{8}$"
        let  CM = "^1(34[0-8]|(3[5-9]|5[017-9]|8[278])\\d)\\d{7}$"
        let  CU = "^1(3[0-2]|5[256]|8[56])\\d{8}$"
        let  CT = "^1((33|53|8[09])[0-9]|349)\\d{7}$"
        let regextestmobile = NSPredicate(format: "SELF MATCHES %@",mobile)
        let regextestcm = NSPredicate(format: "SELF MATCHES %@",CM )
        let regextestcu = NSPredicate(format: "SELF MATCHES %@",CU)
        let regextestct = NSPredicate(format: "SELF MATCHES %@",CT)
        if ((regextestmobile.evaluateWithObject(self) == true)
            || (regextestcm.evaluateWithObject(self)  == true)
            || (regextestct.evaluateWithObject(self) == true)
            || (regextestcu.evaluateWithObject(self) == true))
        {
            return true
        }
        else
        {
            return false
        }  
    }
}