SWIFT COREDATA-循环通过具有“for in”的结果。循环构建单独的数组 [英] SWIFT COREDATA - looping through results with "for in" loop to build separate array

问题描述

SWIFT COREDATA
我在设置for-in循环以从抓取中收集结果时遇到问题。没有问题通过fetch results [index]获取单个结果，但插入for-in循环给我一个错误（类型不匹配）或（类型不包含生成器中的成员）。我想使用抓取结果填充单独的数组。

SWIFT COREDATA I'm having trouble setting up a for - in loop to collect results from a fetch. No problem getting individual results by fetch results[index] but inserting for-in loop gives me an error (type mismatch) or (type does not contain member in Generator). I want to use the fetch results to populate a separate array.

非常感谢您提供的任何帮助。

Any help you can provide is greatly appreciated.

摘录自代码：

import Foundation
import UIKit
import CoreData
// globaals
var pickResult:String?
var pickMultiresult:[AnyObject]?
// add var
var fullnameMulti:[String]?  // array of full names
var i:Int = 0
// end new var
class ClientPicker:UIViewController, UIPickerViewDelegate {
    // connections

    @IBOutlet weak var singleResult: UITextField!
    let managedObjectContext = (UIApplication.sharedApplication().delegate as! AppDelegate).managedObjectContext
    @IBOutlet weak var firstname: UITextField!
    @IBOutlet weak var status: UILabel!
    var lastname:String = ""
    var phone:String = ""
    var email:String = ""

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
 }
 // MARK: ********** block 2 --- findClient ****
    @IBAction func findClient(sender: AnyObject) {
        let entityDescription = NSEntityDescription.entityForName("Contacts", inManagedObjectContext: managedObjectContext)
        let request = NSFetchRequest()
        request.entity = entityDescription
        let pred = NSPredicate(format: "(firstname = %@)", firstname.text!)
        request.predicate = pred

        do {
            var results = try managedObjectContext.executeFetchRequest(request)
            multiresult = results
            if results.count > 0 {
//                let match = results[0] as! NSManagedObject  NOTE: these return correct data for indices 0 and 3
//                let match = results[3] as! NSManagedObject  NOTE: these return correct data for indices 0 and 3 
                status.text = "There are  \(results.count) people named \(firstname.text!)"
            } else {
                status.text = "No Match"
            }
        } catch let error as NSError {
            status.text = error.localizedFailureReason
        }



// for in loop to populate firstnameMulti array
        i = 0
    for i in results{
        var p = i
        let match = results[p] as! NSManagedObject

                /* the following code returns correct fullname when used outside of for loop
                but error when I use the for loop  */
                firstname.text = match.valueForKey("firstname") as? String
                /*****************  concatenate first and last names  ********/
                let first = match.valueForKey("firstname") as? String
                let last = match.valueForKey("lastname") as? String
                // concatenate
                var fullname:String = ""
                fullname = "\(first!) \(last!)"
                singleResult.text = fullname       
        }
}

*/  error: value of type string has no member in Generator */

推荐答案

您正在填充循环中的文本字段的文本，并在每次迭代时覆盖它。这没有任何意义。

You are filling the text of a text field in the loop and overwriting it at every Iteration. That does not make any sense.

要生成全名数组，请获取您的对象并转换为适当的NSManagedObject子类，例如 Person 所以你得到一个 [Person] 数组，然后你可以使用 map ：

To generate an array of full names, fetch your objects and cast to the proper NSManagedObject subclass, such as Person so you get a [Person] array and then you can simply use map:

let nameList = results.map { "\($0.firstname) \($0.lastname)" }

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