如何在swift中访问for循环外的变量

Question

do {
    let results = try context.executeFetchRequest(request)

    for result in results as! [NSManagedObject] {
        var  savepassword = result.valueForKey("savePassword")!     
    }
} catch {

}

// what I want is to be able to access the variable out here
// savepasword

Answer 1

您需要在循环外声明savePassword。您应该注意，如果从查询中返回了多个对象，那么您将得到数组中最后一个对象的值。这可能是你想要的也可能不是你想要的

var savepassword : String?

do {
    let results = try context.executeFetchRequest(request)

    for result in results as! [NSManagedObject] {
        savepassword = result.valueForKey("savePassword") as? String    
    }
} catch {

}

if let savepassword = savepassword {
   // Do something with savepassword
}

Answer 2

var any: Any
do {
    let results = try context.executeFetchRequest(request)
    any = results
 } catch {

}
for result in any as! [NSManagedObject] {
    var  savepassword = result.valueForKey("savePassword")!
}