xcode 核心数据属性类型列表?
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List of Core Data attribute types?
提问by iWizard
I've searched Core Data attribute types but with no success.
我搜索了 Core Data 属性类型,但没有成功。
When I open my Entity and Attribute there are several types:
当我打开我的实体和属性时,有几种类型:
- Integer
- Double
- String
- Boolean
- 整数
- 双倍的
- 细绳
- 布尔值
etc.
等等。
I'm interested if there is some Apple page which explains about every attribute for which type of usage is.
我很感兴趣,如果有一些 Apple 页面解释了每个属性的使用类型。
For example I need an attribute type in which I'll be saving strings of about 1000 characters. Which attribute type do I use for this type of insert?
例如,我需要一个属性类型,我将在其中保存大约 1000 个字符的字符串。对于这种类型的插入,我使用哪种属性类型?
Thanks for help
感谢帮助
回答by trojanfoe
The NSAttributeDescription
class referenceconstants section gives:
在NSAttributeDescription
类引用常数部分提供:
typedef enum {
NSUndefinedAttributeType = 0,
NSInteger16AttributeType = 100,
NSInteger32AttributeType = 200,
NSInteger64AttributeType = 300,
NSDecimalAttributeType = 400,
NSDoubleAttributeType = 500,
NSFloatAttributeType = 600,
NSStringAttributeType = 700,
NSBooleanAttributeType = 800,
NSDateAttributeType = 900,
NSBinaryDataAttributeType = 1000,
NSTransformableAttributeType = 1800,
NSObjectIDAttributeType = 2000
} NSAttributeType;
回答by CrimsonDiego
You can find the list here, specifically described in the constants section.
您可以在此处找到该列表,具体在常量部分进行了描述。
Specifically, typedef enum {
NSUndefinedAttributeType = 0,
NSInteger16AttributeType = 100,
NSInteger32AttributeType = 200,
NSInteger64AttributeType = 300,
NSDecimalAttributeType = 400,
NSDoubleAttributeType = 500,
NSFloatAttributeType = 600,
NSStringAttributeType = 700,
NSBooleanAttributeType = 800,
NSDateAttributeType = 900,
NSBinaryDataAttributeType = 1000,
NSTransformableAttributeType = 1800,
NSObjectIDAttributeType = 2000
} NSAttributeType;
This means the types available to you are:
这意味着您可以使用的类型是:
Undefined/transient, short, integer, long, float, double, NSDecimalNumber, NSString, Boolean, NSDate, NSData, Value transformers, and id
未定义/瞬态、短整数、长整数、浮点数、双精度数、NSDecimalNumber、NSString、布尔值、NSDate、NSData、值转换器和 id