从这里抛出的错误不会被处理

Question

我试图在我的iOS应用程序上解析JSON时遇到此问题:

相关代码:

let jsonData:NSDictionary = try JSONSerialization.jsonObject(with: urlData! as Data, options: JSONSerialization.ReadingOptions.mutableContainers ) as! NSDictionary

/* XCode error ^^^ Errors thrown from here are not handled */

有人能帮助我吗？

Answer 1

let jsonData = try JSONSerialization ...未处理可能的错误.

您可以忽略可能的错误,并在发生错误时崩溃为惩罚:

let jsonData = try! JSONSerialization ...

或返回Optional,所以jsonData是nil错误的情况:

let jsonData = try? JSONSerialization ...

或者您可以捕获并处理抛出的错误:

do {
    let jsonData = try JSONSerialization ...
    //all fine with jsonData here
} catch {
    //handle error
    print(error)
}

您可能想学习The Swift(3)语言