Question

我在以下代码的第四行中遇到以下错误...

线程1：信号SIGABRT ，输出显示无法将类型'JobTableViewController'（0x10a20cb80）的值强制转换为'NSString'（0x10cc5a2a8）。

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    if segue.identifier == "toDetails" {
        let detailController = segue.destination as! JobDetailViewController
        detailController.valueToPass = sender as! String
    }
}

Job.swift：

class Job {
var text: String = ""
let ref: DatabaseReference!

init(text: String) {
    self.text = text
    ref = Database.database().reference().child("jobs").childByAutoId()
}

init(snapshot: DataSnapshot)
{
    ref = snapshot.ref
    if let value = snapshot.value as? [String : Any] {
        text = value["text"] as! String
    }
}

func save() {
    ref.setValue(toDictionary())
}

func toDictionary() -> [String : Any]
{
    return [
        "text" : text,
    ]
}
}

Answer 1

您的问题是，您在performSegue中将self（类型为JobTableViewController）作为sender参数发送

self.performSegue(withIdentifier: "toDetails", sender: self)

然后将其投射到

sender as! String

将其转换为

self.performSegue(withIdentifier: "toDetails", sender:"sendedStr")

无法将类型'TableViewController'的值转换为'NSString'

1 个答案: