我用来打开视图控制器时出错： - EXC_BAD_INSTRUCTION（code = EXC_I386_INVOP，subcode = 0x0）

Question

我在视图控制器中使用标签栏，但是当我运行项目然后点击投诉标签时，它会显示错误，如

  

致命错误：＆＃39;尝试！＆＃39;表达式意外地引发了错误：错误Domain = NSCocoaErrorDomain Code = 3840＆＃34;字符0周围的值无效。＆＃34; UserInfo = {NSDebugDescription =字符0周围的值无效。}：file /Library/Caches/com.apple.xbs/Sources/swiftlang/swiftlang-800.0.63/src/swift/stdlib/public/core/ErrorType.swift,line 178

请告诉我如何解决此错误。

import UIKit
class ComplaintViewController: UIViewController ,UITableViewDataSource,UITableViewDelegate {
    @IBOutlet weak var mytableview: UITableView!
    ////step->1
    var ComplaintList:[Complaint]?
    var complaint:Complaint?
    override func viewDidLoad() {
        super.viewDidLoad()
        requestForProductList()
        mytableview.reloadData()// Do any additional setup after loading the view.
    }
    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()// Dispose of any resources that can be recreated.
    }
    private func requestForProductList() {
        ///step->2
        var c_url = const_url + ("complaint_view.php")
        let url = URL(string:c_url)
        var request = URLRequest(url: url!)
        request.httpMethod = "POST"
        request.addValue("application/json", forHTTPHeaderField: "Content-Type")
        let task = URLSession.shared.dataTask(with: request) { (result, response, error) in
            guard error == nil else {
                print(error!.localizedDescription)
                return
            }
            let resultDict = try! JSONSerialization.jsonObject(with: result!, options: .allowFragments)
            DispatchQueue.main.async {
                self.parseData(result: resultDict as! [String : Any])
            }
            print(resultDict)
        }
        task.resume()
    }
    private func parseData(result:[String:Any]) {
        ///step->3
        let complaintMain = ComplaintMain(fromDictionary: result)
        ComplaintList = complaintMain.complaint
        mytableview.reloadData()
    }
    //MARK:- Tableview datasource methods
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        if let list = ComplaintList {
            return list.count
        }
        return 0
    }
    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(withIdentifier: "mycell", for:indexPath) as! ComplaintTableViewCell
        let complaint = ComplaintList?[indexPath.row]
        cell.lbltype.text = complaint?.ctype
        let reqUrl = URL(string: const_url + (complaint?.url)!)
        let data = NSData(contentsOf: reqUrl!)
        if data != nil
        {
            cell.myimage.image =  UIImage(data:data as! Data)
        }
        return cell
    }
    func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        complaint = ComplaintList?[indexPath.row]
        performSegue(withIdentifier: "select", sender: nil)
    }
    override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
        let vc3 = segue.destination as! ComplaintdidselectViewController
        vc3.complaint = complaint 
    }
}