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EnumDataTypeAttribute Class

Definition

Enables a .NET enumeration to be mapped to a data column.

public ref class EnumDataTypeAttribute sealed : System::ComponentModel::DataAnnotations::DataTypeAttribute
[System.AttributeUsage(System.AttributeTargets.Field | System.AttributeTargets.Method | System.AttributeTargets.Parameter | System.AttributeTargets.Property, AllowMultiple=false)]
public sealed class EnumDataTypeAttribute : System.ComponentModel.DataAnnotations.DataTypeAttribute
[<System.AttributeUsage(System.AttributeTargets.Field | System.AttributeTargets.Method | System.AttributeTargets.Parameter | System.AttributeTargets.Property, AllowMultiple=false)>]
type EnumDataTypeAttribute = class
    inherit DataTypeAttribute
Public NotInheritable Class EnumDataTypeAttribute
Inherits DataTypeAttribute
Inheritance
Attributes

Examples

The following example shows how to replace the numeric value of an enumeration with the corresponding declaration.

public enum ReorderLevel
{
    Zero = 0,
    Five = 5,
    Ten = 10,
    Fifteen = 15,
    Twenty = 20,
    TwentyFive = 25,
    Thirty = 30
}

[MetadataType(typeof(ProductMD))]  
public partial class Product
{  
    public class ProductMD
    {  
        [EnumDataType(typeof(ReorderLevel))]  
        public object ReorderLevel { get; set; }  
    }  
}  
Imports Public Enum eReorderLvl  
    zero = 0  
    five = 5  
    ten = 10  
    fifteen = 15  
    twenty = 20  
    twenty_five = 25  
    thirty = 30  
End Enum  
<MetadataType(GetType(Product_MD))>  _  
Public Class Product  
    Public Class Product_MD  
        <EnumDataType(GetType(eReorderLvl))>  _  
        Public Property ReorderLevel As Object  
        End Property  
    End Class  
End Class  

Remarks

This class lets you map the underlying value in a column to a corresponding enumeration constant name. This lets you define an enumeration that contains descriptive values that correspond to database values, and then use the enumeration constant names instead of the database values when data is displayed.

Constructors

EnumDataTypeAttribute(Type)

Initializes a new instance of the EnumDataTypeAttribute class.

Properties

CustomDataType

Gets the name of custom field template that is associated with the data field.

(Inherited from DataTypeAttribute)
DataType

Gets the type that is associated with the data field.

(Inherited from DataTypeAttribute)
DisplayFormat

Gets a data-field display format.

(Inherited from DataTypeAttribute)
EnumType

Gets or sets the enumeration type.

ErrorMessage

Gets or sets an error message to associate with a validation control if validation fails.

(Inherited from ValidationAttribute)
ErrorMessageResourceName

Gets or sets the error message resource name to use in order to look up the ErrorMessageResourceType property value if validation fails.

(Inherited from ValidationAttribute)
ErrorMessageResourceType

Gets or sets the resource type to use for error-message lookup if validation fails.

(Inherited from ValidationAttribute)
ErrorMessageString

Gets the localized validation error message.

(Inherited from ValidationAttribute)
RequiresValidationContext

Gets a value that indicates whether the attribute requires validation context.

(Inherited from ValidationAttribute)
TypeId

When implemented in a derived class, gets a unique identifier for this Attribute.

(Inherited from Attribute)

Methods

Equals(Object)

Returns a value that indicates whether this instance is equal to a specified object.

(Inherited from Attribute)
FormatErrorMessage(String)

Applies formatting to an error message, based on the data field where the error occurred.

(Inherited from ValidationAttribute)
GetDataTypeName()

Returns the name of the type that is associated with the data field.

(Inherited from DataTypeAttribute)
GetHashCode()

Returns the hash code for this instance.

(Inherited from Attribute)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
GetValidationResult(Object, ValidationContext)

Checks whether the specified value is valid with respect to the current validation attribute.

(Inherited from ValidationAttribute)
IsDefaultAttribute()

When overridden in a derived class, indicates whether the value of this instance is the default value for the derived class.

(Inherited from Attribute)
IsValid(Object, ValidationContext)

Validates the specified value with respect to the current validation attribute.

(Inherited from ValidationAttribute)
IsValid(Object)

Checks that the value of the data field is valid.

Match(Object)

When overridden in a derived class, returns a value that indicates whether this instance equals a specified object.

(Inherited from Attribute)
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
ToString()

Returns a string that represents the current object.

(Inherited from Object)
Validate(Object, String)

Validates the specified object.

(Inherited from ValidationAttribute)
Validate(Object, ValidationContext)

Validates the specified object.

(Inherited from ValidationAttribute)

Explicit Interface Implementations

_Attribute.GetIDsOfNames(Guid, IntPtr, UInt32, UInt32, IntPtr)

Maps a set of names to a corresponding set of dispatch identifiers.

(Inherited from Attribute)
_Attribute.GetTypeInfo(UInt32, UInt32, IntPtr)

Retrieves the type information for an object, which can be used to get the type information for an interface.

(Inherited from Attribute)
_Attribute.GetTypeInfoCount(UInt32)

Retrieves the number of type information interfaces that an object provides (either 0 or 1).

(Inherited from Attribute)
_Attribute.Invoke(UInt32, Guid, UInt32, Int16, IntPtr, IntPtr, IntPtr, IntPtr)

Provides access to properties and methods exposed by an object.

(Inherited from Attribute)

Applies to