您可以(无损)在UInt64和之间进行转换Int64:
// Set:
obj.int64Property = Int64(bitPattern: uint64Value)
// Get:
let uint64Value = UInt64(bitPattern: obj.int64Property)
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您可以定义uint64Value为托管对象类的计算属性来自动执行转换:
@objc(MyEntity)
public class MyEntity: NSManagedObject {
public var uint64Property: UInt64 {
get {
return UInt64(bitPattern: int64Property)
}
set {
int64Property = Int64(bitPattern: newValue)
}
}
}
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