如何在swift中调用时编码电话号码

Question

我试图将电话号码格式化为＆＃34; 01-800-234-0445＆＃34;用于调用屏幕。在尝试执行呼叫之前，我可以将其格式化为正确的格式，但是当呼叫在＆＃34; 018002340445＆＃34;格式。我认为这与编码有关，这是我到目前为止所做的：

phone =＆＃34; 01-800-234-0445＆＃34; （用于executeCall手机参数）

private func executeCall(phone:String){

let formattedPhone = phone.addingPercentEncoding(withAllowedCharacters: NSCharacterSet.urlQueryAllowed)!//this formatting doesn't appear to be doing anything

if let url = URL(string: "tel://" + formattedPhone), UIApplication.shared.canOpenURL(url) {
    if #available(iOS 10, *) {
        UIApplication.shared.open(url)
    } else {
        UIApplication.shared.openURL(url)
    }
}
}