所以我正在向解析本地数据存储区写入一堆数据,但是想要在固定新表之前删除旧表。问题是它似乎没有删除,我最终得到同一个表的多个条目。
这是将数据写入本地数据存储的代码。
class func buildHistoryPart(selectedPartId: String? = nil) {
let query = PFQuery(className: "Part")
query.includeKey("fromPack")
query.findObjectsInBackground { (objects, error) in
if error != nil {
print(error!)
} else if let parts = objects {
for object in parts {
//if the objectID is equal to the id of the part received
if object.objectId == selectedPartId {
// if the fromPack column has data
if let fromPack = object.object(forKey: "fromPack") as? PFObject {
// create the class name from the pack name of the selected part
if let className = (fromPack.object(forKey: "packName") as? String) {
// creeate PFObject to rretrieved fields to
let historyClass = PFObject(className: className) as PFObject
//add the objects to new class
historyClass.add(object.objectId as Any, forKey: "partId")
historyClass.add(object.object(forKey: "partName") as Any, forKey: "partName")
historyClass.add(fromPack.object(forKey: "packName")!, forKey: "packName")
historyClass.add(fromPack.objectId as Any, forKey: "packId")
// unpin the old data
PFObject.unpinAll(inBackground: [historyClass], withName: "pinnedHistory", block: { (success, error) in
if success {
// if successful pin the new data
PFObject.pinAll(inBackground: [historyClass], withName: "pinnedHistory")
}
})
}
}
}
}
}
}
}
它没有取消固定,每当我运行该函数时,我最终会在LDS中得到一堆表。
-------------------编辑--------------------
我得到的工作因为我无法使用他们记录的“withName”属性来使用解析函数,只是调用一个专门查询有问题的表的函数,如果它在那里删除它。它工作正常,但如果有人知道为什么我的原始代码不工作id爱知道。
称之为取代以上所有的unpin:
class BuildHistory {
// unpinall doesnt seem to wok so force it and return result
class func removeOldTable(className: String, completeBlock: @escaping (Bool) -> Void) {
let queryRem = PFQuery(className: className)
queryRem.fromLocalDatastore()
queryRem.findObjectsInBackground { (objects, error) in
if objects != nil {
PFObject.unpinAll(inBackground: objects)
completeBlock(true)
}
}
}
class BuildHistory {
// unpinall doesnt seem to wok so force it and return result
class func removeOldTable(className: String, completeBlock: @escaping (Bool) -> Void) {
let queryRem = PFQuery(className: className)
queryRem.fromLocalDatastore()
queryRem.findObjectsInBackground { (objects, error) in
if objects != nil {
PFObject.unpinAll(inBackground: objects)
completeBlock(true)
}
}
}