ColumnAttribute Class
Definition
Important
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Associates a class with a column in a database table.
public ref class ColumnAttribute sealed : System::Data::Linq::Mapping::DataAttribute
[System.AttributeUsage(System.AttributeTargets.Field | System.AttributeTargets.Property, AllowMultiple=false)]
public sealed class ColumnAttribute : System.Data.Linq.Mapping.DataAttribute
[<System.AttributeUsage(System.AttributeTargets.Field | System.AttributeTargets.Property, AllowMultiple=false)>]
type ColumnAttribute = class
inherit DataAttribute
Public NotInheritable Class ColumnAttribute
Inherits DataAttribute
- Inheritance
- Attributes
Examples
<Table(Name:="Employees")> _
Public Class Employees
Private _LastName As String
' …
<Column(Storage:="_LastName", DbType:="NVarChar(20) NOT NULL", _
CanBeNull:=false)> _
Public Property LastName() As String
Get
Return Me._LastName
End Get
Set
If ((Me._LastName = value) _
= false) Then
Me.OnPropertyChanging("LastName")
Me._LastName = value
Me.OnPropertyChanged("LastName")
End If
End Set
End Property
End Class
[Table(Name="Employees")]
public class Employees
{
private string _LastName;
// …
[Column(Storage="_LastName", DbType="NVarChar(20) NOT NULL",
CanBeNull=false)]
public string LastName
{
get
{
return this._LastName;
}
set
{
if ((this._LastName != value))
{
this.OnPropertyChanging("LastName");
this._LastName = value;
this.OnPropertyChanged("LastName");
}
}
}
}
Remarks
Use this attribute to designate a member of an entity class to represent a column in a database table. You can apply this attribute to any field or property that is public
, private
, or internal
.
Only those entity class members identified as columns are persisted when LINQ to SQL saves changes to the database.
Use commas to separate multiple properties on the attribute.
Constructors
ColumnAttribute() |
Initializes a new instance of the ColumnAttribute class. |
Properties
AutoSync |
Gets or sets the AutoSync enumeration. |
CanBeNull |
Gets or sets whether a column can contain null values. |
DbType |
Gets or sets the type of the database column. |
Expression |
Gets or sets whether a column is a computed column in a database. |
IsDbGenerated |
Gets or sets whether a column contains values that the database auto-generates. |
IsDiscriminator |
Gets or sets whether a column contains a discriminator value for a LINQ to SQL inheritance hierarchy. |
IsPrimaryKey |
Gets or sets whether this class member represents a column that is part or all of the primary key of the table. |
IsVersion |
Gets or sets whether the column type of the member is a database timestamp or version number. |
Name |
Gets or sets the name of a column. (Inherited from DataAttribute) |
Storage |
Gets or sets a private storage field to hold the value from a column. (Inherited from DataAttribute) |
TypeId |
When implemented in a derived class, gets a unique identifier for this Attribute. (Inherited from Attribute) |
UpdateCheck |
Gets or sets how LINQ to SQL approaches the detection of optimistic concurrency conflicts. |
Methods
Equals(Object) |
Returns a value that indicates whether this instance is equal to a specified object. (Inherited from Attribute) |
GetHashCode() |
Returns the hash code for this instance. (Inherited from Attribute) |
GetType() |
Gets the Type of the current instance. (Inherited from Object) |
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) |
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) |
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
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