CKQuery，如何从记录中获取所有字段？

Question

我已经弄清楚如何搜索我的 CKrecord 并仅使用下面的代码显示一个字段中的字符串。

我有几个问题..（我是新手）

我可以搜索并且不区分大小写吗？
如何搜索记录中的所有字段，然后显示匹配的所有字段？

我正在制作一个参考应用程序，因此您可以搜索 BBC1 等所有与 BBC1 相关的内容（即在该 recordID 中）显示。

import UIKit
import CloudKit
import MobileCoreServices

class ViewController: UIViewController {

    @IBOutlet var addressField: UITextField!
    @IBOutlet var commentsField: UITextView!

    let container = CKContainer.defaultContainer()

    var publicDatabase: CKDatabase?
    var currentRecord: CKRecord?

    override func viewDidLoad() {
        publicDatabase = container.publicCloudDatabase
        super.viewDidLoad()
    }


    @IBAction func performQuery(sender: AnyObject) {
        let predicate = NSPredicate(format: "serviceName = %@", addressField.text!)
        let query = CKQuery(recordType: "SystemFields", predicate: predicate)
        publicDatabase?.performQuery(query, inZoneWithID: nil, completionHandler: ({results, error in
            if(error != nil) {
                dispatch_async(dispatch_get_main_queue()) {
                    self.notifyUser("Cloud Access Error",
                        message: error!.localizedDescription)
                }
            } else {
                if results!.count > 0 {
                    let record = results![0]
                    self.currentRecord = record

                    dispatch_async(dispatch_get_main_queue()) {
                        self.commentsField.text = record.objectForKey("Location") as! String
                    }
                } else { dispatch_async(dispatch_get_main_queue()) {
                    self.notifyUser("No Match Found",
                        message: "No record matching the address was found")
                    }
                }
            }
        }))
    }

    func notifyUser(title: String, message: String) -> Void
    {
        let alert = UIAlertController(title: title,
                                      message: message,
                                      preferredStyle: UIAlertControllerStyle.Alert)

        let cancelAction = UIAlertAction(title: "OK",
                                         style: .Cancel, handler: nil)
        alert.addAction(cancelAction)
        self.presentViewController(alert, animated: true,
                                   completion: nil)
    }
}

Print Results Output

Answer 1

根据 Apple 的 CKQuery Class Reference，您应该能够通过使用记录字段的标记化搜索来完成这两项工作：

To perform a tokenized search of a record’s fields, use the special operator self. A tokenized search searches any fields that have full-text search enabled, which is all string-based fields by default. Each distinct word in the tokenized string is treated as a separate token for the purpose of searching. Comparisons are case- and diacritic-insensitive. These token strings may be found in a single field or in multiple fields.

下面是清单 5 示例（在 Swift 中）：

Listing 5 - Matching a field containing one or more tokens

var predicate = NSPredicate(format: "self contains 'bob smith'")

以及清单 6 示例（在 Swift 中）：

Listing 6 - Matching a field containing multiple tokens

var predicate = NSPredicate(format: "self contains 'bob' AND self contains 'smith'")

最后，查看有关 Indexes and Full-Text Search 的信息，因为您在 CloudKit 中的记录配置会影响搜索的字段（和性能）。

编辑：进一步说明您的用例：

由于您正在使用 addressField.text 的内容进行搜索...

您必须决定是否要匹配：

选项 1 - addressField.text 中的任何单个词匹配记录中任何字段中的任何词。

在 Swift 2.2:

let predicate = NSPredicate(format: "self contains %@", addressField.text!)

选项 2 - 当所有个词在 addressField.text 中都在记录的一个字段中（尽管不一定按相同的顺序）。

在 Swift 2.2:

// creates a compound predicate to match all words in a string
// returns: nil if input was empty, otherwise an NSPredicate
func createPredicateForMatchingAllWordsIn(string: String) -> NSPredicate?
{
    guard !string.isEmpty else { return nil }
    var predicateList : [NSPredicate] = []
    
    let words = string.componentsSeparatedByString(" ")
    for word in words {
        if !word.isEmpty {
            predicateList.append(NSPredicate(format: "self contains %@", word))
        }
    }
    
    return NSCompoundPredicate(andPredicateWithSubpredicates: predicateList)
}

let predicate = createPredicateForMatchingAllWordsIn(addressField.text!)

如果您想进行额外的过滤，例如仅显示单词匹配顺序的记录，您可以在客户端进行。（CKQuery class 仅支持完整 NSPredicate class 提供的谓词行为的一个子集。）

CKQuery，如何从记录中获取所有字段？

CKQuery, how to fetch all Fields from Record?

ios

swift

cloudkit